New to forum but have been searching the archives for awhile and have not found a solution to my specific problem. It could be as simple as a hardware mismatch.
I've had a set of 8L16 (4qty) hooked up for about 6 months. I've only monitored the SG a couple of times since the install (nothing unusual). However, just was about to add 4 more to the bank and checked the old...they were sitting around the 75% charge state while the WBjr said fully charged.
I'm a bit worried to add the other ones into the mix until I figure out my current settings. If there's anyone out there that would have an idea of where to start? I will acknowledge to you that I am not as well versed in this area of life...as I should be. We just moved off grid and would love to have a bit of help.
Hardware:
4 (current) Deka 8L16 6 volt 370ah batteries
4 Hyundai s250mg 250watt multicrystalline panels (series/parallel)
Midnite Classic 150
Settings:
EQ: 28.4
ABSORB: 28.3
FLOAT: 27.0
ABSORB Time: 1hr30min
Temp Comp Charge: -5.0 mV
Output Amps: 48
Input Amps: 60
Ending Amps: 7 (based on a midnite classic video - so probably part of my problem...)
Rebulk: 8volts
Please feel free to email me or send a message. I don't have extremely good internet at this location of service...so, what I can research is done on memory and notes.
Hi robertwilliams, Welcome to the Forum.
So, the target SGs for fully-charged batteries is 1.275.
In looking around on the web, for charging specs on these batteries, seems like a good starting point is about 29.4 V. This should be Temperature Compensated at -- 5 mV/Cell/C. This is customary for Flooded batteries, perhaps for your batteries, it could be as low as -- 3 mV/Cell/C.
The Absorb time required for full charge will depend upon the Depth Of Discharge (DOD) that the battery has experienced in the previous discharge.
An Ending Amps setting of 7 A may be good, bu the correct value will depend upon some monitoring and adjusting this value, and/or the Absorb voltage.
How long have the present batteries been in service? It can be a bit of a problem adding batteries to some that have been in service for some time. About six months age difference may be about the limit of what is desirable.
Will look further for charging specs on your batteries.
FWIW, Vic
Thanks for the reply Vic.
The current batteries were installed I believe in mid June. I was aware of the disparities of adding batteries of different dates/ages of use. However, I need the extra capacity.
So, when you say a good starting point for charge - I understand that as an absorb voltage of 29.4? Is that correct?
I just downloaded the Midnite Local App onto a laptop. Would this be of any use? Such as recording a log of amps in the absorb stage so that I can adjust my ending amps.
Reading a couple of other posts you have made, it seems I should have my absorb time set out quite aways in time while I'm observing the amp curve.
Also, the batteries I picked up today were supposed to be fully charged (I called a week ahead - and they were in fair condition). Anyways, upon the SG readings of the new batteries, I thought I shouldn't add them to the bank until they were up to charge as well. So, currently, the new ones are on the CC, while the old ones sit. Can I take SG readings right after they are pulled from the system (ie. just got done charging) or should I wait awhile. I'm currently under the impression I should wait a day. If this is the case, I will probably be babysitting this system in the dark for awhile...or is it better to find ending amps while using normal loads?
Thanks again Vic!
East Penn Deka absorb range
28.80V â€" 29.40V
Float
27.60V â€" 28.20V 27
Temp compensation
-3 mv
If they are new batteries you may start with lower voltage of the range above.
I would put at least 2 to 3 hours absorb - and ending amps 5 or 6 and check SG to confirm they are charged .
So you want to watch SOC and watch system amps - easiest way is to monitor on MyMidnite - system amps should start to level off around 100% SOC. That would be your ending amps - confirm with SG readings .
What efficiency do you have for your SOC setup ?
Here is East Penn Deka specs
http://www.eastpennmanufacturing.com/wp-content/uploads/Renewable-Energy-Charging-Parameters-1913.pdf
Local Status app is great monitoring tool , so is Grahams Classic Android app if you have android device.
Also you can set everything up with Local Status app and save copy of parameters so when you do firmware update you can easily restore everything .
Not sure where you are but it can be tough this time of year up north to get batteries topped up with short days and cloudy weather especially if you are running batteries way down. You should have generator to charge in your system to keep batteries healthy .
With settings you had ending amps was likely too high , absorb time too short, absorb voltage too low .
Larry
Thanks Larry.
The new batteries will hopefully get juiced according to the old settings, better than nothing. I won't get back over to the site until tomorrow evening. I hope all works. When I had left it, there was still daylight but the controller kept going into resting mode once I hooked up the new batteries. I didn't see any odd voltage drops on the PV in, or Batt V. I have encountered this once before...and I don't recall what the culprit was.
I will make some changes tomorrow evening. I will also hopefully be able to log some of the charge rates - 2 days from now - on the local app.
Thanks for the charge specs. Would it help to equalize (I've never done it before) the older batteries before connecting them all together? I guess, what I'm asking, what would be the best sequence of events for adding these newer batteries to the system?
You want to make sure your two parallel strings of batteries are wired correctly so they both get same charge.
See this
http://www.smartgauge.co.uk/batt_con.html
I guess I would charge each series string up on their own to 100 % , then put them together .
But it won't hurt to charge them up together now if they are both low.
It also doesn't hurt to equalize . See those specs I posted - and equalize with temp compensation for 2 hours. There is check mark on equalize to use temp compensation for that . But you won't be able to get them equalized until you have good sunny day when the batteries are not too far down. You really only need to equalize if some cells are getting lower than others to balance them but once a month is what is often recommended for maintenance. Or more or for longer if some of the cells are lower than others and are taking longer to get the same as others. Check every cell with SG readings.
How many amps are you taking out of your batteries - what SOC are you going down to ?
Larry
Whether you start using the new ones or the old ones you need to bring them both up to FULL charge.
Do you have a charger that you can power with your generator? If so put it to use soon as possible, both sets of cells need to be as similar in charge-state as possible before combining them. The results of checking the SGs will let you know if there is an issue...
Make a chart to record your SGs and number all the cells. This will be invaluable at a later date, monthly or so checks should also get recorded.
hth
Another quick question - Objectively, I understand that ending amps should be reflective of when the amps start to taper of at a rate of <.10amps/hr. Subjectively, are they are based on a number around 1% of the battery's aH rating? or the battery BANKS aH rating?
Once I get both sets topped off this week, I'd like to know where/when I should be looking to end amps? Specifically, after I join the (2) 370aH banks together, collectively 740aH.
are they are based on a number around 1% of the battery's aH rating? or the battery BANKS aH rating?
If you are calling a BANK a string of cells, they are one and the same...
Do not mix different Ahr rated cells in a bank or parallel strings of cells... big NO NO... mucho problema...
your target should be in the neighbourhood of 7A per string, and you will have 2 strings,and each string will vary somewhat around its number..
If you think about what you are using , it is WATTS and Watt hours, so you need to replace these
Watts = Volts x Amps
Hi robbertwilliams,
First, assume that each string of batteries in your bank are 8L16LTP-DEKA, or, perhaps 8L16LTP.
Yesterday, did poke around on the Net, and found several Deka Docs on charging. The ones that I quoted above, were for Flooded Lead Antimony batteries, and therefore the --5 mV/Cell/C spec noted in that document.
It appears that Deka has changed to Lead-Calcium for their Flooded batteries -- this changes the charge voltages and the Temperature Compensation value to -3 mV.
Did find only one reference to the SG for fully-charged cells, at 1.275.
What are you using as the SG for a full charge?
What brand, or type of Hydrometer are you using to measure the SG of each cell of the battery bank?
Here is a good Article on measuring SGs, from Surrette Battery. The SG for fully-charged batteries is one difference between the Chart in this article, verses your battery SGs:
http://support.rollsbattery.com/support/solutions/articles/4347-measuring-specific-gravity
Regarding the EA setting, Deka suggests a value between 1 and 2 % of 20 Hour Capacity (370 Ah). The proper value of EA will depend somewhat on the Absorb voltage setting that is being used.
For EA, would suggest beginning at about 1.5% or your bank's total Capacity -- 370 for a single string or, 740 for two parallel strings, if your Absorb voltage (Vabs) is in about the middle of the suggested range from Deka.
When using EA to terminate Absorb, you will want to set the Absorb time to a value that is above the longest Absorb time you would ever expect. Absorb time varies directly with the Depth Of Discharge (DOD) that the battery experienced in the previous discharge.
In general, it takes a number of discharge/charge cycles for Lead Acid batteries to develop full-capacity, and become stable. You may have some difficulty using EA, particularly with a six, or so month difference in the ages of the two strings of your battery. Usually, the number of cycles will be from about 20, to about 70. The shallower the cycle, the longer it may take. You may not notice this effect, but perhaps if could cause some unpredictability when using EA.
Better Post this now, the Inet may crash soon. Vic
... MORE,
It is unfortunate, that for Renewable Energy (RE) charging specs, Deka suggests using Rate-of-change as a suggested terminator for Absorb, as almost NO RE chargers, like CCs can use this method. However, they do also state between 1 - 2% of 20 hr Capacity.
There is still some Jitter in the battery charge current, as measured by the WBjr, and the WBjr current display on the MNGP may not be updated for each reading that the WBjr sends to the Classic. boB did reduce this jitter, several years ago, but if it were further-reduced, it would make watching the rate-of-change if battery much easier to read with one's eyes. But, still, the WBjr is a great addition to the MN CCs.
Then, regarding your battery bank going from 370 Ah, to 740 Ah:
Depending upon your location, your 1,000 PV array might be able to provide about 25 Amps charge current to the battery at peak sun, on a clear day. This is about 7 percent of battery Capacity (C), when you double the battery C, this charge current is diminished to about 3.5% of C. For a weekend cabin or similar this is not too bad, as the battery charge state can catch up during the week, of little or no battery use. Although, we do not know your approximate location, solar conditions, now, or the intended use of your system.
For systems that are cycled daily, the suggested range of charge rates for Flooded batteries is around 10% of C, with 13% being about the maximum charge rate, recommended. Deka does have specific recommendations on maximum charge rates that are a bit different, but, you might want to increase the size of your PV array, or, at least have a genset and a charger that can charge the battery bank, should if not get sufficiently charged from your PVs.
Vic
Thanks everyone for your help and interest.
Just switched settings on the charge controller. Eq=28.8 Abs=28.8 Float=27 EndingAmps=4 Absorb Time=4 hrs Temp comp = -3mv
Since I swapped to the newer bank to charge it up (note, both times I've monkeyed with it have been in the late afternoon - no direct sun), the CC goes from Float in Resting, and then vice versa. I ended up doing a complete reset today. Tomorrow is going to be overcast, snow, and 6F. So, this figuring stuff out is going to take a bit of time. I need to find a "no" job.
I should add a little more info to help in finishing the picture, and maybe painting it too.
We are moving into a 20ft yurt in the Black Hills of South Dakota. No water (at least not running) and minimal electric needs. The site gets full sun for 3/4 of the daytime hours (today 1/10/2017 - visible at 9 and invisible at 3:30).
Currently, we have:
9 LED lights (all 9w/piece) with all hooked up to a dimmer
A small dorm size refrigerator (not currently on the system)
An HRV - 50watts and is programmable(heat recovery ventilator to help with our air quality in such a small space, definitely needed in such a small space with only wood heat and humidity issues) - also not currently installed, hope to run a laptop (or two)
Energystar TV
Internet modem
Router
Schneider electric Combox
Schneider Electric SW2524 Inverter/Charger
A coffee pot that runs for 5 minutes and then shuts off
Occasional use of a small vacuum (650 running watts)
AND possibly a 4 cu ft chest freezer which would be outside in an outbuilding in the winter months
That is all that I can think of, off the top of my head. It's currently still under construction. So, it's hard for me to imagine something I haven't lived in.
I think once I can get the CC dialed in, then both battery banks up to full charge, we should be in good shape. After taking the SG readings tonight, the older bank looks like it may need an equalize. But for the next few days to a week, I will be playing with some adjustments to charge times, etc.
Question: With the midnite local app, do I or don't I need internet? Or is it possible to just network it to the router (just like I have my Schneider Electric Combox currently) and talk to it that way? Or can I directly plug the ethernet into the laptop (that didn't work with the combox).
The current generator that I have is a 3000 running watt machine, with a 220 20amp output. I could do one of two things; buy an external charger to top the bank off or wire up the inverters' built in charger. What would be most effective? If I need to buy an external charger, any recommendations?
Thanks again. I'm very happy to have some people to help me with this. I've also attached an excel worksheet with my SG readings from tonight
Hi robbertwilliams,
Thank you very much for all of the added detail about your yurt, location, settings, SG readings, and loads.
IMO, your charge settings need to be changed:
Would suggest setting the Absorb voltage at the high end of the recommended range -- 29.4 V, because, your SG readings show that your batteries are NOT being fully charged.
In Winter, it is common for us to need to set the Absorb voltage a bit higher than the Summer setting, as the number of hours of good sun are short, and higher Vabs will allow more battery charging to be done in fewer hours.
YES, it appears that each string of batteries need an EQ, based upon the variation in SG readings.
Your EQ voltage setting is too low. Would suggest at a minimum setting for Veq at about 30.6 V. This is the high suggested setting for Veq. IMO, the EQ voltage should be Temperature Compensated ... set the Classic to YES for compensating the EQ voltage.
Would set the Float voltage (Vflt) to the middle of the range -- 27.4 V.
The SW2524 should be a good battery charger, when using the genset. So try this. You should not need any other battery charger, is this inverter/charger is setup correctly.
Normally one would try to charge the batteries from the genset, starting early in the morning, and allow it to charge the batteries into the middle of the Absorbtion stage, shut off the genset, and try to finish th
e charge with PV, when the sun is due to shine most of the day. This should save fuel.
There is a Video, where the procedure of setting up a Router, connected to a Classic, is shown ... will post that Link. Using a Router with the Classic is quite simple ... even I could figure out that!!
Link to the Router setup Video:
http://midnitesolar.com/video/videoPlay.php?video_ID=39&videoCat_ID=3
Black Hills in Winter !! You folks are tough!
... Vic
OOOoooppppsss, Just edited the above post, but notice that you are now online, so please note the Link to the Router setup video, and did also edit the body of the post a bit ... Thanks, Vic
You don't need internet to connect with Local Status App - just plug Classic into router, then your computer into router and Local Status App should find your Classic and connect to it. I have used both DHCP and also set up Classic with static address -- both work fine and depends on how you want to set up network or other stuff on there.
If you want to use the MyMidnite online graphing then you do need to have internet because it sends data to their server. You need to log in and set up account there and get your Classic registered, etc. That is really nice to view accumulated data on graphs you can change to your liking.
If you have Android phone or tablet look up Grahams Classic app on forums or available on Playstore - great interface that you can select F temps and change between watts and amps and see system amps more easily as compared to general output amps of classic. This app will find Classic on the network - no internet needed for this either.
You want to use your inverter for charging if possible - save a lot of $$ on a charger if you already have inverter charger and it has smarts built in to regulate charging.
I should add that the Classic on some firmware versions or for whatever reason sometimes does mess up and need reset to work right with Local Status app or Mymidnite. There is a setting in Classic to reset automatically at midnight ( time ) . You may want to enable that if you have problems and save some hassle .
Larry
Quote from: robbertwilliams on January 10, 2017, 08:37:29 PM
Question: With the midnite local app, do I or don't I need internet? Or is it possible to just network it to the router (just like I have my Schneider Electric Combox currently) and talk to it that way? Or can I directly plug the ethernet into the laptop (that didn't work with the combox).
RW;
You no not need internet. You may need a local network with an ethernet hub or just what is known as a crossover cable.
Depending on what operating system(s) you use on your computer you may get away with a direct connection ethernet port to ethernet port. Several things affect this but easiest way is a small 4 port ethernet hub both devices attach to. A wireless router might suffice for the hub if the computer has wifi.
If that makes sense? I have done it several different ways, eternet hub, direct and wifi router. What you could do kind of depends on your geekiness factor ;D.
Tom
Little Update - Got the necessary wire and plug to hookup the inverter/charger to the generator. I'll be working on that for the next few days. Also, the new and easier to read hydrometer shows up today, as well as a new fluke meter to replace the meter I stepped on :(.
Thanks again for all your help everyone. I'll keep you posted as I learn more.
Well, the new batteries have been through their first day of "real" charging. Yesterday, it was overcast and snowy. So, today, they made it to float with a absorb set time of 4hr, and ending amps at 4 (not sure which occurred first.
However, I received my new hydrometer today, a Hydrovolt. I checked all SG of the new and newly charged batteries, as well as checking the old batteries again with the new hydrometer to compare readings. Note: the old hydrometer was the glass tube type with a old school mercury type thermometer on the barrel portion of the unit.
The readings are insanely different than they were three days ago, specifically regarding the old set of batteries that haven't been charging. I even pulled electrolyte, took a reading, dumped it out, repulled, and so on. Most cells I took at least three different readings. All of the readings were much higher than a few days prior. Check my chart out. Is this Hydrovolt accurate? or was the hydrometer I had before just junk?
Questions: how close should the SG readings be between cells on each battery? and on each bank? The battery university website only suggests an equalization charge if the batteries have an SG difference of 0.030 or more.
If the CC reads SOC 100%, does the CC still go through all the stages (bulk, absorb, etc)? or does it just skip and go to float? If it skips, how can I get it to realize the batteries still need a charge?
I'm assuming the SG numbers on the new batteries will continue to improve as they receive more full days of charging.
Let me know what you think. I'll be there the next three days to do an equalize if needed and will be finishing up hooking the wire up to the charger.
Thanks again.
Skip days, .... unless you have specifically set this, the CC will go through all stages to FLOAT...
.
To make sure it is trying to get to the End Amp setting, and that that is achieved raise the Absorb time to 5 hours or 6 if needed.
The Classic or the Local App will tell you the time in Absorb and Float... adjust as needed if still not there..
At this time of the year you would do well to do a genny run in the early AM to go through BULK and into Absorb, at about the time the sun can support the high V and Amps at the start of Absorb, then let the PV take over and finish the Absorb and into float if there is enough sun time.., If you don't get there day 1 run the gen earlier and longer... pray to the SUNGOD clear skies!!!
yes your first Hydrometer might be the cause of variance... the Hydro-Volt has been reported here as a good dependable unit...
hth
The Classic SOC reading does not control the charging. It is a reference guage and is only as accurate as you set it up to be and then only so accurate.
The Classic starts charging Bulk until it gets to Absorb voltage, then holds the absorb voltage by cutting down current as needed. It will stay in Absorb until either the Absorb time runs out , or until it reaches ending amps which ever comes first. When it goes to Float the SOC changes from whatever it said to 100%
What you want to do is watch the SG , when it gets to whatever battery company specs say is charged , then take note of what your ending amps was at that time. Then watch and confirm you get the same results some other days. You can adjust the SOC to be closer to reading correctly by changing the efficiency setting on it . Or just know it goes to 100% SOC when it goes to Float. It doesn't matter so much if it goes 100% a bit before it goes to Float - you want to know that your battery is really full by confirming with SG reading .
Don't know what to say about your differing readings except that maybe the other hydrometer you had wasn't temperature compensated ?
I have an inexpensive refractometer which shows very accurate on a scale and you can calibrate it using distilled water. But those are a bit of pain to use because you have to put drops on it and rinse off and be careful putting acid up near your eyes.
Larry
Hi robbertwilliams, thanks for the update.
Believe that you have read the Article noted previously:
"Here is a good Article on measuring SGs, from Surrette Battery. The SG for fully-charged batteries is one difference between the Chart in this article, verses your battery SGs:
http://support.rollsbattery.com/support/solutions/articles/4347-measuring-specific-gravity
"
Personally, would draw two samples and expel them, then draw the third sample and use that for measurement.
Keep the Hydrometer vertical (plumb) while taking the readings.
I did buy three Hydrovolts, a few years ago, when MidNite began distribution of this Hydrometer. I got relatively large variations on successive draws on a given cell. Sometimes the scales would stick together, requiring a rap on the top of the battery case to cause the scales to move. This, plus the very short sample tube made the Hydrovolt relatively difficult to use, and the readings (to me) a bit suspect. So reverted to the tried-and-true Freas Glassworks Hydro, which has very repeatable readings. The issue with the Hydrovolt's short sample tube probably is probably only an issue on batteries with a large electrolyte reserve (space above plates for electrolyte).
It is very, very important to rinse any Hydrometer three or four times after a measuring session, using Distilled Water.
A Hydrometer should give very repeatable readings on successive sample draws beyond the third draw -- only one or two points variation.
New batteries usually need to be cycled 30 - 70-ish cycles before they stabilize. So variations in SG readings could be seen, as the battery becomes "finished".
A variation of 10 points or so, for a fully-charged battery should be fine. Many manufacturers suggest an EQ for variations of about 20, or more SG points.
You appear to be using an SG of 1.265 as fully-charged. If so, did this information come from Deka?
The SOC reading that is determined by the Classic using the WBjr, is only a rough indication of actual SOC. There are many variables that go into calculating SOC, and most battery monitoring devices cannot keep track of all of these, and we users of batteries would not know what values to enter, if the monitor had the ability to keep track of all of the variables.
My CC makes all of its decisions on charging, while ignoring the stated SOC data.
Thanks, Vic
Quote from: Westbranch on January 12, 2017, 11:31:24 PM
the Hydro-Volt has been reported here as a good dependable unit...
IT's CLOSE , BUT not as good as my 1965 imperial glass unit.
I find it the best to check many against all & then I have ONE who is the MASTER . CLEAN it & pull it out to check the rest .
Same as any TOOL .
Best to spend time measuring true & know .
VT
Ok, I definitely didn't drop just under a hundred bucks for a Freas hydrometer. The glass tube I have is
https://www.amazon.com/gp/product/B0050SFVHO/ref=oh_aui_search_detailpage?ie=UTF8&psc=1#Ask (https://www.amazon.com/gp/product/B0050SFVHO/ref=oh_aui_search_detailpage?ie=UTF8&psc=1#Ask)
If trying to verify SG via the scale/digital balance method, after the weight is taken, I'm assuming I still need to factor in the temperature compensation, correct?
The one thing I didn't do, and I wish I had, was measure the SG with both devices today. I guess I'll try that tomorrow.
Thanks
Hi robbertwiliams,
When you mentioned the brand name of the Hydrometer that you were using, did find it on Amazon. Looks like it may be fine.
The Freas Hydros in use here are about 11 years old, and have been very reliable and repeatable. When they were purchased, they were about $40, and were sold by NAZ Wind & Sun. Where did you find the Freas at almost $100 .... perhaps directly from Freas??
We have several known accurate Hydros here, those in use are all the glass tube/glass float variety, so, if one gets broken, there are still others that can do a comparable job.
Regarding Temperature Compensation. Hydrometers need this compensation, because they are measuring the Density of the electrolyte. The weight of the electrolyte should not change with temperature, so should not need compensation ... if this what you were wondering about.
It is very nice to have a known sample of electrolyte that can be your reference standard.
SO, one QUESTION; How is it that you have determined the SG for your fully-charged Deka batteries? Was this from a Deka document? ??
Thanks, Vic
Did anyone mention you can test a hydrometer by testing pure distilled water?
distilled water should read 1.000... at 20 degrees C. (68 F)
Just in case you did not know.
Tom
P.S.
I found my refractory hydrometer to be both accurate and easy to use. Some do not, however.
Hi robbertwilliams,
One good way to check the average State Of Charge (SOC) of a multi-cell battery is to measure its Resting voltage, and Temperature Compensate the voltage reading. A Rested battery is one that has not been charged or discharged for about six hours. A Rest of 12 hours should be better.
You could average the SG readings from each Hydrometer, measure the average electrolyte temperature, apply the temperature compensation of SGs and to voltage measurements, and see how each Hydro compares to the approximate SG from Rested battery voltage.
I did find a Deka battery manual for Flooded batteries, and that DID confirm that the target SG for full-charge, IS 1.265.
In that manual, could not find the Temp Compensation value for voltage. Are you using -- 5 mV/Cell/C?
Later, Vic
Deka always says -3 mv per cell in everything I have ever seen - and on document I linked earlier.
Larry
Yea Larry, Thanks ... but, there are several docs out there that either omit the Temp Comp value, or DO say --5 mV/Cell/C, from resellers (and/or at Deka - forget, have been looking at too many links to recall exactly) that are listing the Deka 370 Ah Flooded L-16s:
http://store.affordable-solar.com/site/doc/Doc_Flooded%20Charging1_20091028104431.pdf
The above doc is dtd 2006 IIRC, AND curiously notes that the Reference temperature is 20 C -- have never seen that before.
AND, robbertwilliams also DID mention in the first post, that --5 mV was being used, so, was trying to find what is the actual true value ... had wondered, if there was some data packet/Maunal supplied with the batteries that stated charge parameters, etc.
It has looked like Deka has gone to Lead-Calcium for many/most/perhaps all of their batteries (a bit surprising to me).
Thanks, Vic
I am using 1.265 as a full SG, and it is currently set at -3mv/c. Vic, that document is the same that I was given when I asked the retailer (first set purchased) for charge specs, and that is all they could find. I haven't been following any real rubric in the recent week. I've been taking suggestions and spec documents while using them collectively.
Tom, thanks for the hint in regards to SG of distilled water. Neither one of my hydrometers will read down to 1.0.
I did however have pretty good luck with measuring out 15ml of solution and dividing its weight in g by volume in ml. The end result brings me to trust my glass OTC hydrometer (not 100% confident in the built in temp compensation thermometer) and to DISTRUST the Hydrovolt, which is back in the package and ready for return. I couldn't get consistent readings with the hydrovolt, just consistently different readings.
I'll be ordering a Freas No. 1 from Chief Aircraft, 35 bucks with shipping.
The charge today, I arrived around 11:30am, was already in Float. This was with a 4hr duration and ending amps (classic not shunt) set at 3.7. The SG readings, especially in the battery/cell "new 4-3" had not improved. I've since brought ending amps back to zero and will see what happens after 4hrs of absorb. Frustration has ensued.
I hooked up all the necessary wiring for the generator to charge via the inverter but I can't find my batt temp sensor for it. Will the midnite one work on the Schneider electric inverter? They look nearly identical. The set limits for the built in charger are much different than the CC's.
Any idea of max temp setting for EQ? I've read anywhere from 125 to 145. I'm kind of nervous to do an EQ but I think it is a must. I'm shooting to try it out on Sunday. I plan to keep a close eye on it. All pointers would be appreciated greatly.
Thanks everyone!
Also, I got the local app to work and despite its few added features that the CC display lacks, it seems to lack a bit of other things. Are there any graphs ? Or any real way to record ending amps other than staring st the screen and watching a clock?
If you have internet register on MyMidnite and get that going - you can easily choose and see battery volts, ending amps, SOC , etc - pick and choose which ones.
You can see the days history and as you drag the mouse along it will show you the readings on the left - in this capture the white vertical mouse line is showing the readings at that particular time .
You can see that it was just before ending amps at 10.6 and then it goes to float . You can see the sharp drop on the graph . These are new batteries and I am still figuring out if I should use ending amps and at which value .
Larry
(//)
OK... you SET the EA value and the Classic will end the Absorb stage at that value
ie if it is set to 0.1A, ABSORB will end when the WBjr measures that there are .1Amps going into the battery...
EA is set in one of the 3 categories at the bottom of the screen ONCE you have chosen CONFIG
yes there is a facility in the L. App to view and you can choose the units you want to watch
From memory, the values are set using the DATA on the top of the dashboard and LIVE on the bottom of the dashboard...
hth
Quote from: robbertwilliams on January 13, 2017, 08:46:24 PM
I am using 1.265 as a full SG, and it is currently set at -3mv/c. Vic, that document is the same that I was given when I asked the retailer (first set purchased) for charge specs, and that is all they could find. I haven't been following any real rubric in the recent week. I've been taking suggestions and spec documents while using them collectively.
Tom, thanks for the hint in regards to SG of distilled water. Neither one of my hydrometers will read down to 1.0.
I did however have pretty good luck with measuring out 15ml of solution and dividing its weight in g by volume in ml. The end result brings me to trust my glass OTC hydrometer (not 100% confident in the built in temp compensation thermometer) and to DISTRUST the Hydrovolt, which is back in the package and ready for return. I couldn't get consistent readings with the hydrovolt, just consistently different readings.
I'll be ordering a Freas No. 1 from Chief Aircraft, 35 bucks with shipping.
The charge today, I arrived around 11:30am, was already in Float. This was with a 4hr duration and ending amps (classic not shunt) set at 3.7. The SG readings, especially in the battery/cell "new 4-3" had not improved. I've since brought ending amps back to zero and will see what happens after 4hrs of absorb. Frustration has ensued.
I hooked up all the necessary wiring for the generator to charge via the inverter but I can't find my batt temp sensor for it. Will the midnite one work on the Schneider electric inverter? They look nearly identical. The set limits for the built in charger are much different than the CC's.
Any idea of max temp setting for EQ? I've read anywhere from 125 to 145. I'm kind of nervous to do an EQ but I think it is a must. I'm shooting to try it out on Sunday. I plan to keep a close eye on it. All pointers would be appreciated greatly.
Thanks everyone!
First, good that you found the Freas #1 Hydro. And that you feel that you have confirmed the accuracy of the glass Hydro.
Fine on using 1.265 and -- 3 mV.
IMO, EA probably did end the Absorb, today, because it is hard to believe that you could do Bulk, AND four hours of Absorb by 11:30 AM, especially in the far North.
Believe that the Battery Temp Sensor (BTS) for the Schneider equipment is different than the Outback and MN products. The only Schneider BTSes that I've seen are medium grey in color, and have a metal tab with a hole in so it can be mounted on a battery terminal, if that might help you find it. The color may have changed ...
So, you have the Schneider SCP, or Combox, or whatever is necessary for you to change the inverter/charger settings from Defaults to what you need for your Flooded batteries. Usually, Default settings are so low, as to be only marginally useful. It is possible that the Default EQ voltage is at a very low Absorb voltage.
But, since you were wondering about the Max temperature for an EQ, perhaps you do have the necessary SW gizmo to change from the Defaults ...
Even without the SW's BTS, you could still do the EQ, if you have the correct Schneider gizmo to allow setting correct voltages for your batteries. You could use the Classic's Temps menu, or the Local App (LA) to see the battery temp, and do a manual comp, at --3 mV/Cell/C.
EQing does raise battery temperature. It would surprise me, if your battery temperature RISE during a three hour EQ would exceed 25 or so degrees F.
So before you EQ the battery, you will want to complete the Absorb stage, and would guess that the EQ might require 2 - 3 hours, or even more.
The LA does have the ability to plot WBjr Amps, and CC output Amps, and a number of other things. So, select "Data", and then "Live". Now, you can choose the parameters that you want to watch.
Of course, the data is sent to your computer, so, the LA needs to be running on the computer to have the data saved.
For me, the resolution for the LA on screen display is not sufficient to be able to see the rate of change of WBjr current (or CC output current) to be useful in seeing the appropriate EA value ... the Scale Factor is too large. Absorb is entered at about 70 or so amps, but would like to be able to resolve a fraction of an amp on the graph ... probably when exported, and massaged, it could be useful. The LA is still a very useful package, and it is FREE!! Thanks MidNite!
ENUF for now, Vic
You can get data points every 2 seconds with the Local App. The LA has to remain running to collect this data. I’ll start it in the morning and let it run all day with it set to a long Absorb time and a low EA. Set the DATA â€" LIVE what to chart to all values. This will make a messy looking graph in the LA what what you want to do is Export that data as a CSV file and import it to Excel. You can then see all the data. You will need to convert the Time and set the time zone in the cell as explained on the Export file. You can then make a graph of the WBjr Amps going into the Battery. When you see that line start to flatten out that would be what you set your EA at.
Ryan has made 5 You Tube video of every thing about the LA. See MN web site under Document and Videos, then Under Classic IIRC. Great and very helpful to understand the LA.
See sample graph below. In this graph EA would be set at around 5.5 - 6.0 Amps as the WBjr amp reading is a little noisy and to go to Float it has to be at that value for a set period of time and any noisy spike will cancel the time and have to start over. But you'll get the idea. There is a bug in the time data that can be easily corrected. But won't get into that now.
Hi John,
Thanks for the info, and the graph. That representation would be more useful ... sure wish that we could set the scale on the LA's Data - Live ... maybe later on that.
Thanks, Vic
What does everyone know about the T-Comp Limit settings on the classic?
Today it was super sunny and CC sat in the absorb stage through the 4hrs, batt amps (classic measurement) at 2.5-3.5, batt voltage at 29.2. Everything seemed like it was broken, panels pulling only 50 or so watts.
I decided I'd switch the charge over to the old battery bank that has been sitting for about a week. The watts shot right up to around 250-300 and slowly tapered back down to 60watts. Then it occurred to me that the battery voltage (29.2) was the peak again. That number looked familiar so I cycled through the menus and found the max t-comp limit was set to 29.2. Coincidence? I changed it to 32 (as well as changing the old low limit of 26.4 to 24.4). Then the wattage on the panels shot right up again.
So lost...
For some strange reason all the Training Videos including the LA ones are no longer on the Web site. At least I can't reach them from the US West Coast. I've pinged Ryan on it to see if he can get them back.
Hi robbertwilliams,
The Default Temp Comp Limit Defaults are very narrow, to try to be safe for those with Sealed batteries.
IMO, set the Classic upper limit to a voltage that you would expect that the Classic will never see, and likewise with the lower limits. So, EQing a cold battery, you might see 32.5 V, or so, so I would set the upper limit around that. Do not know the Hi voltage shutdown (might be HVD, or similar) is on the SW inverters, though.
The lower temp comp limit affects compensation while charging a warm/hot battery.
Personally, would set the Classic Temp compensation for EQ = YES, BTW.
IMO, your intuition was quite good.
Good Luck, Vic
I thought he had flooded L16
Larry
Thanks Vic! I'm hoping to move forward tomorrow. I'm going to hold off a day on the EQ until I find out that the T-Comp Limit settings were the culprit; I'd like to see it first hand. This way I'll be able to have the computer hooked up and recording tomorrow's charge session.
Wish I had more info/news for today but that cut the day pretty short. I did however have sometime to play with my new amp clamp out at the panels...not as exciting as you'd think but it did pass the time.
Thanks everyone.
Quote from: ClassicCrazy on January 14, 2017, 06:22:56 PM
I thought he had flooded L16
Larry
Hi Larry, is the above quote aimed at me?
YES, indeed, he does have Flooded batteries!
Vic
Quote from: Vic on January 14, 2017, 06:05:54 PM
Hi robbertwilliams,
The Default Temp Comp Limit Defaults are very narrow, to try to be safe for those with Sealed batteries.
IMO, set the Classic upper limit to a voltage that you would expect that the Classic will never see, and likewise with the lower limits. So, EQing a cold battery, you might see 32.5 V, or so, so I would set the upper limit around that. Do not know the Hi voltage shutdown (might be HVD, or similar) is on the SW inverters, though.
The lower temp comp limit affects compensation while charging a warm/hot battery.
Personally, would set the Classic Temp compensation for EQ = YES, BTW.
IMO, your intuition was quite good.
Good Luck, Vic
Yeah Vic - I thought you mentioned sealed batteries above - I didn't think flooded were considered sealed since they can gas off all they want.
Larry
Larry,
All of the discussion about measuring SGs, target SG for full-charge, Hydros, etc, plus the Deka battery links, reference to elevated EQ voltages, etc, DO indicate that the batteries in question are indeed Flooded.
The above reference to Sealed batteries, was an attempt to simply explain why the Default Temp Comp Limits (Sealed batteries) in the Classic (and a number of other CCs & inverters were SO narrow), and the suggestion to significantly widen these limits for robbertwilliams' Deka Flooded batteries ... that is all that I was trying to do ...
Thanks, Vic
Oh - I understand what you mean now Vic - makes sense !
Larry
Well, not sure if I have anything to report after today. The "incoming" watts were at about 70w, and voltage at 34.5ish while in the absorb stage. The battery peaked out at 29.8volts and the WBJr amps were at 1.6-2.0, kinda bouncing up and down but pretty much consistent. So, I'm not sure if opening up the temp comp limits did much of anything.
I feel like something else is limiting my charge...what gives me this feeling is that incoming watts sit around 70w, but when I turn the inverter on and start to draw on the system, the incoming watts go up to 175-200w (even more if I turn more stuff on).
This is just becoming a bit overwhelming...the whole move in the middle of winter, not having this power thing figured out, our dog diagnosed with cancer, etc.
I did, however, fire up the generator and inverter/charger. It seems to work well but am unsure of the settings. The inputs are different than that of the Classic. I've attached a couple pics that show what the Schneider electric Charger is looking for. It's asking for amps instead of volts for the three charge stages. Somewhere I believe I came across an article on C/5 for the bulk, C/10-15 for absorb, and C/20 for float...but I can't seem to find it.
And what is Temperature Compensation Set Voltage? And why is it 29.6? Just curious, doesn't look like I can change it.
Ok, my pictures are too big, even compressed, to add them as attachments.
The SW is looking for the following:
Battery Type
Maximum Charge Rate - 100%
Max Bulk Charge Current - 48A
Max Absorb Charge Current - 37A
Max Float Charge Current - 2A
Charge Cycle - Set to 3 stage
Default Battery Temp - Not in Degrees but stated as "cold" or "hot" or "warm" (set to COLD)
Recharge Voltage - 25.0V
Absorption Time - 240min
Charger Override Enable/Disable - Disable
Do these settings look ok?
Robbertwilliams, Do your data sheets list a max charge rate in AMPS or as % of Caoacity? If not I would be inclined to set it to the 37A which is 10% of your battery capacity.
The rest looks OK to me. pay it cautious.
Please add a description of you system in your signature line.
hth
The temperature compensation is the adjusted charging voltage which is set by the Classic. So you put in -3mv and if the batteries are cold it will adjust the absorb voltage to charge higher than the setpoint.
For example
I have 28.8 set for Absorb Voltage . with -3 mv in the temp compensation the Temperature Compensated Voltage is now 29.9 volts because my batteries are -7 C . So they charged to 29.9 v today for Absorb. It also compensates float and equalize voltages ( optional on equalize voltage. ) So no you can't change that temperature compensated voltage unless you change the -3mv setting to something else.
What you describe with incoming watts going up when you turn on a load is how it is supposed to work if there is more available power than the batteries need.
Lets say you are charging 2 amps into the battery ( system amps ) but the panels have total 5 amps available. When you turn on a 3 amp load the incoming power will go up ,and 2 amps will still go to the battery but 3 amps is going to go to the load. Of course amps in are not the same as amps out because they are different voltages. Watts is always the same though.
Again - the way the Classic charging works is Bulk you get all available power from panels into batteries. Once it gets to Absorb voltage ( which is temperature compensated ) the Classic will hold the voltage at the Absorb setpoint but decrease the amps to maintain that voltage.
At the end of absorb time or ending amps which ever comes first it goes to Float.
Not sure what to tell you about your other charger - don't have enough info on it to say.
Larry
Robbert, you said
I feel like something else is limiting my charge...what gives me this feeling is that incoming watts sit around 70w,
Yes you are correct, the internal resistance of the battery is most likely pushing back against the arrays output> CC's output current
Quote from: robbertwilliams on January 15, 2017, 08:24:52 PM
Well, not sure if I have anything to report after today. The "incoming" watts were at about 70w, and voltage at 34.5ish while in the absorb stage. The battery peaked out at 29.8volts and the WBJr amps were at 1.6-2.0, kinda bouncing up and down but pretty much consistent. So, I'm not sure if opening up the temp comp limits did much of anything.
I feel like something else is limiting my charge...what gives me this feeling is that incoming watts sit around 70w, but when I turn the inverter on and start to draw on the system, the incoming watts go up to 175-200w (even more if I turn more stuff on).
This is just becoming a bit overwhelming...the whole move in the middle of winter, not having this power thing figured out, our dog diagnosed with cancer, etc.
I did, however, fire up the generator and inverter/charger. It seems to work well but am unsure of the settings. The inputs are different than that of the Classic. I've attached a couple pics that show what the Schneider electric Charger is looking for. It's asking for amps instead of volts for the three charge stages. Somewhere I believe I came across an article on C/5 for the bulk, C/10-15 for absorb, and C/20 for float...but I can't seem to find it.
And what is Temperature Compensation Set Voltage? And why is it 29.6? Just curious, doesn't look like I can change it.
Ok, my pictures are too big, even compressed, to add them as attachments.
The SW is looking for the following:
Battery Type
Maximum Charge Rate - 100%
Max Bulk Charge Current - 48A
Max Absorb Charge Current - 37A
Max Float Charge Current - 2A
Charge Cycle - Set to 3 stage
Default Battery Temp - Not in Degrees but stated as "cold" or "hot" or "warm" (set to COLD)
Recharge Voltage - 25.0V
Absorption Time - 240min
Charger Override Enable/Disable - Disable
Do these settings look ok?
Hi robbertwilliams,
Several thingsl
When you changed the Temp Comp Limits on the Classic, did you press 'Enter' ? Please check that you saved those changes -- Enter does that. Otherwise, the Classic might revert to the previous Default values at Midnight.
Also, you mentioned, that in Absorb that the Input voltage was about 34.5 (assuming that this is on the Classic). BUT, in your initial Post in this Thread, you said, "4 Hyundai s250mg 250watt multicrystalline panels (series/parallel)"
If your input voltage is only 34.5 V, and you have two PVs in series, something is amiss.
If there are any clouds PV production can be reduced significantly, but normally one might expect that in this cases that the input voltage would be above about 60 - 70 V on a cold day but the power production would be low, due to the clouds.
Are you certain that you have two PVs in series in each string?
If so, you might want to try a different PV Mode for the Classic -- Legacy P&O. In cloudy conditions, this different Mode can help. The standard Mode of Solar, does its MPPT Sweep very fast, but at times in cloudy conditions, it can sweep the PV input voltage down to about 4-5 volts above the battery voltage, and this just kills PV power production.
What Firmware version is the Classic running ?? Press the Status button ( the small round one on the right), about six or so times, and note what the Classic FW version is.
You will get on top of this. In the Winter, in your part of the world, things change a lot, so there are quite a few factors that can be affecting your system.
Regarding the Schneider SW inverter, unfortunately, for the rest of us who do not use any of the Schneider stuff, Schneider seems to choose to use completely different descriptors for almost every mode, and setting for their solar hardware, so, folks like me, do not know that they are thinking, and what these unusual words mean for the operation of their gear, there seems to be NO translator available.
Thanks for answers to the above questions. You will get on top of the situation, soon. Vic
Vic, hit the nail on the head. If your 4 panel are 2 series 2 parallel according to your panel specs you should be seeing around 60 volts on input of Classic not 34 volts. Something is wrong here.
Also what are all the checked setting for all items in the Tweats menu? Curious if LOWMAX is enabled?
That something wrong is my memory. I just ran through it in my head; I have two parallel strings.
When I wired the panels I went with the setup to increase current, not volts.
Should I have done it differently?
I'm working on getting the signature description - hopefully later today. I understand that trivia isn't fun for everyone.
Should lowmax be enabled? I'll check it out this afternoon. (Edit: LMAX is ON) I'll also check to see which firmware. Thanks again. I really do appreciate this.
Edit:
The more I'm reading now...the better understanding. I think my main reason for doing the panels in parallel was that then they'd be less susceptible to shade variances between the panels. But it seems that I should've connected them in parallel, or at least series/parallel to adjust for the voltage drop from the panels to the controller (approx 50ft with 6 gauge).
Hi robbertwilliams,
If all of your PVs in parallel, there can often be insufficient input voltage for an MPPT CC to find a good voltage for the PVs to produce very much power.
Have not looked at the specs of your PVs, but most Poly PVs are in the range of about 29 - 31 volt Vmp. This is simply too low, and is worse yet for Flooded batteries, that need an EQ, even worse than that, would be cold batteries that need an EQ, as EQ needs a relatively high voltage, and so on.
EDIT: BTW, here is a footnote copied from the MidNite String Sizing Tool:
" ... Most all MPPT controllers will want to see a minimum of 130% of the actual high battery voltage. So if we have a 48v battery and it has an Equalize voltage if 62.3 volts than we would multiply that by 130% and we would need a minimum of 81 volts on the input on the hottest day of the year in order to have enough headroom for the MPPT to work ..."
Here is the Link to the Classic Sizing Tool:
http://www.midnitesolar.com/sizingTool/displaySizing.php
Will look for the specs on your PVs.
More later, Vic
Robert ,
Could you get some photo's of how you have your panels wired up to the combiner box ?
Also some screen shots of Local Status App would help too - if you have that running.
Pictures worth a thousand words sometimes as the saying goes.
By the way - I run into that photo is too large to attach all the time too. I use Irfanview to half the size of the photo's.
Also you can lower the size image that your camera takes and then you won't have to resize them to attach.
Larry
And to add to what Vic posted. If you are 50 ft from panels to controller you need to make it round trip for DC voltage drop. Here's a spread sheet that was posted here a long time ago for calculating Voltage drops. In this calculator you have to double the actual distant. So from Panel to Controller that would be 100 ft.
You can change the values in blue in the spreadsheet.
Still playing around. I had adjusted the charge voltages on Monday morning. I accidentally had plugged in the 24v voltages for the monobloc AGM, instead of monobloc FLA from the EastPenn chart. So, it appears, based on the log, that it charged .6kw that day. But then today, it sat in resting. Must be just some dumb luck that Monday was a day of blazing clear sun, and today was a bit overcast...no idea.
So, based on what you all have said, I decided to switch my all parallel system over to, what I had originally quoted in the beginning of the thread, a series/parallel. I'm assuming that the 130% MPPT rule has been keeping the controller at "resting". In theory, with the new EQ set at 30.2v, my the controller would want to see 39.26v to start functioning (something that will never happen if I left the panels in full parallel).
Tomorrow will be the first day with this new setup. Hopefully, this will be when the ball starts rolling.
Question 1, no one has gotten back to me on whether I should have "LMAX" on or off?
Question 2, in the original setup of the panels, I had (2) 20amp breakers in the combiner box. I had (2) positive MC4 and (2) negative MC4 connections coming out of the combiner box. Each connector then when into a 2way "Y". So, each "Y" had either a set of (2) positives or (2) negatives. With the new setup, I got rid of the "Y's", but I still have the (2) 20amp breakers. SO, with that said, now that it is running in series parallel, do I need to resize these two breakers for each series string?
Hi robbertwilliams, thanks for the Update.
IMO, your system will perform much better with two PVs in series per string.
Just my opinion, again, but one would need to add to that EQ voltage of 30.2 volts, any temperature compensation for the coldest temperature that you would ever expect the battery to endure. SO, YES, the 2S X 2P PVs should help a lot.
Sorry about not commenting on LoMax. You should be fine with this set to OFF, it is not commonly used.
And, good question about the size of the breakers in the Combiner. You really do not need any breakers there, with only two strings of PVs. With three or more strings in parallel, you would need a breaker for each string, the maximum size of the breaker in that situation would be the Max Fuse size spec for your PVs -- often this is 15A for recently manufactured PVs. So, you should be fine with those two 20 A breakers for now.
As stated previously, you might want to plan for some additional PVs in the future, just given the size of your battery bank's Capacity.
Good work on rewiring your PVs. Good Luck, please let us know how you are doing.
Vic
Quote from: robbertwilliams on January 17, 2017, 10:26:00 PM
Question 1, no one has gotten back to me on whether I should have "LMAX" on or off?
Question 2, in the original setup of the panels, I had (2) 20amp breakers in the combiner box. I had (2) positive MC4 and (2) negative MC4 connections coming out of the combiner box. Each connector then when into a 2way "Y". So, each "Y" had either a set of (2) positives or (2) negatives. With the new setup, I got rid of the "Y's", but I still have the (2) 20amp breakers. SO, with that said, now that it is running in series parallel, do I need to resize these two breakers for each series string?
If you have your PV wired 2S2P for the 60V input to the Classic you should disable LOMAX.
I'm a little confused with how you had the Combiner box wired. You said you had two(2)positives and two (2) neg coming OUT of the Combiner. Not sure how that came about.
You should series connect 2 panel outside the Combiner box. Pos to Neg and have a pos from one panel and the Neg for the other panel run into the Combiner. Do the same with the other two panels. You now have two strings with 2 panels in series. When the positives of both strings are connect to the two breakers in the Combiner they are paralleled as the breakers are bussed together. All negatives go to the Neg buss bar in the Combiner. Coming out of the Combiner should be a single positive from the breaker buss bar and a single negative from the negative buss bar.
That said with both breakers in the Combiner ON and the Pos out of the Combiner connected to a PV Breaker at the Classic and the other side of that breaker connect to PV + at the Classic and the Negative from the Combiner connect directly to the PV - at the Classic you should see around 60V as the Voltage on the PV + and - terminals of the Classic when you have some sun on the two strings of panels.
Sorry if this is so confusing I should have just drawn a picture. A picture would have saved all the words.
Vic can correct me if said something wrong trying to write it out.
robbert, here are a couple of schematics, 1 parallel and the other series.... they are for the KID but just look at the panels and circuit breakers part..
hth
Parallel http://www.midnitesolar.com/pdfs/Kid_12V_2p_Par_REV_B.pdf
series http://www.midnitesolar.com/pdfs/Kid_24V_2p_Series_REV_B.pdf
There are some good pictorials in the Kid owners manual on how to wire panels in series / parallel configuration .
http://www.midnitesolar.com/pdfs/Kid_24V_4p_Series+Par_REV_B.pdf
Larry
ha ha - great minds think alike Westbranch !
Quote from: ClassicCrazy on January 18, 2017, 01:06:12 AM
There are some good pictorials in the Kid owners manual on how to wire panels in series / parallel configuration .
http://www.midnitesolar.com/pdfs/Kid_24V_4p_Series+Par_REV_B.pdf
Larry
Perfect Larry & WB. Much better that my long diatribe on the topic. Just wasn't sure how Robert was discribing his connections from the Combiner. Thanks for the links that should let him verify his connections for us.
Thanks Vic, Larry, John, and WB.
I believe I've got it wired correctly and the schematic did confirm that.
I think the confusion came with the use of the word "out" instead of "in"...but if you're familiar with any of Midnites MNPV Combiner boxes that are setup with MC4 "in's", then you've seen what I have before. I know they don't make an MNPV3 with MC4 but I retrofitted this one to fit the bill.
I'll get LMAX turned off and hopefully we will be in good shape.
Love the help. Priceless
Hi robbertwilliams,
Good work on getting your PVs wired 2S 2P, this should make a large difference in PV production, and, thanks for adding the Signature with your system details.
Getting PV string voltage in an efficient operating range for MPPT CCs is a common difficulty, particularly with 60-cell PVs, that are primarily designed for Grid-connected systems. Those with experience with PWM CCs, or replacing a PWM with an MPPT CC, can run into this issue ... you are not alone in this situation.
Given that the original string of batteries may well have been undercharged for some time, doing an EQ on that string, perhaps by itself might be in order, and then do an EQ with both strings connected. This could be done over a one week, or so period - IMO.
Believe that you mentioned that you have a clamp-on DC Ammeter, which will be a large help in monitoring the current balance twix the strings during charge and discharge of the battery.
Water consumption can be a fairly good gauge of how well your batteries are being charged.
You are certainly welcome for the advice. If we are lucky, we ALL are learning, and all have benefited from all of the help and experience that so many folks bring to this (and other) Forums.
Thanks to all contributors! Vic
Thanks Vic.
Well...I know you live by the trusted Freas Hydrometer...I just picked up a refractometer and am loving the ease of use and clear readings. However, I haven't calibrated out of the box. I need to perform the SG test of Glycerin, or some other readily available chemical with an SG above 1.1. Also, does anyone have a good routine habit of using the refractometer, especially in terms of cleaning the acid off after each cell test? Currently, I'm wiping with wet paper towel, and then with a dry one (I'm not feeling like this is the best method).
So, out of the box, and judging by the spacing of the SG scale in the optics, distilled water does appear to read 1.0 on the imaginary scale. With that said, the readings yesterday on the new bank were quite different than that of the hydrometers. The new bank lowest cell reading was 1.265 and the highest was 1.3. The old bank had a low reading of 1.28 and a high of 1.3. I did not do any individual cell voltage tests.
The charge went quite well with the new series/parallel setup. However, the watts never exceeded 115, and the amps never over 4. So, question, does the CC kind of have a clue as to what the batteries will take while its going through a charge? It seems that if I had the bank drawn down much more, like to an SOC of 85, I remember the wattage hitting higher numbers. So, that is where the confusion lies. I'm still trying to wrap my head around how the CC works, what numbers/readings to look for as normalcy/irregularity, and when those numbers should or shouldn't occur.
BTW, either since I rewired the PV or changed the shade setting to ON, my SPD300 at the PV's have LEDs on well into the dark evening.
EDIT: I just found a site with the identical scale and description of calibration with distilled water. http://www.planetextech.com/profiles/blogs/calibration-and-operation-of-the-rf40-c-battery-coolant
The refractometer is calibrated correctly. The SG's read yesterday are correct.
Since I'm getting readings higher than 1.265 (full charge SG according to DEKA), should I lower my charge settings? Suggestions? (Currently set at -- EQ 30.2, ABSORB 29.2, FLOAT 27.5)
The SG's taken yesterday are in the excel chart attached.
Hi robbertwilliams,
Good that you have a Refractometer, I have never used one, but, when calibrated it should be accurate and repeatable.
Briefly, the Classic CC should begin every day trying to fully recharge the batteries, unless Skip Days have been set to some value other than zero, in the Advanced menu.
The Classic should begin the day in Bulk MPPT when there is some sun (even filtered sun). Bulk is a stage that supplies the maximum available charge current to the batteries. As Bulk progresses, the battery voltage will rise, and generally, the current will also rise, because the amount of PV power available increases as the sun rises higher in the sky. Of course clouds and any shading will have a large effect on the amount of PV power available.
With your PVs rewired for 2S 2P, you should see the input voltage to the Classic in the 65 - 80 volt range, depending on the amount of sun, and temperature of the PVs, shading, etc.
When the CC is in Bulk, and Absorb, what input voltage to the Classic are you seeing? This is very important information.
When the batteries have not been discharged very deeply, the Bulk stage will be short. Depending on how you have set the Classic, the Absorb stage may end by time, or EA, as you know.
The batteries control the amount of current that the CC supplies as charge current into the batteries, this is called Acceptance. Of course any loads on the inverter will add to the amount of current that the CC delivers, up to the ability of the PVs to supply that amount of power ... you know this.
If you have a situation where there are passing clouds, then, you might want to try a different Mode for the Classic -- Legacy P&O, in the Mode menu. This Mode can help the Classic deliver maximum power with widely varying PV power conditions. Legacy P&O sweeps for the Maximum Power Point much more slowly than does Solar Mode, and can be helpful at times.
Are you seeing the Classic display "Shading" on the MNGP display at times?
More Later, Vic
I'm getting around 66-68v coming in. And yes, such as seen last night, no light (FLOAT - PV SHADING).
"Since I'm getting readings higher than 1.265 (full charge SG according to DEKA), should I lower my charge settings? Suggestions? (Currently set at -- EQ 30.2, ABSORB 29.2, FLOAT 27.5)"
Robert ,
If the SG readings are where they are supposed to be I would lower the Absorb and Float voltages. The East Penn Deka gives a range so go to the lower part of the range and see if those do the job. If so stay lower and raise the voltage to the higher parts of the range as your batteries get older and may need it .
I have a refractometer and pretty much do what you described , rinse with distilled water and then dry with a cloth. That is where the bulb type hydrometer has the advantage because you just squirt it out and go on to the next cell so it is much faster and easier to make sure you have gotten a good mix of the electrolyte for a sample each time. So it is possible to use both devices to check SG use one to confirm the other . I usually used the bulb of one to take the samples for the other anyway because that way I knew I was stirring up the electrolyte well to get the couple drops that the refractometer needs. It is a bit messy though.
Larry
Today, around noon, the CC was in Bulk mode and was not charging (no watts and SOC at 97% where it was a day ago). So, I shut it off and started it back up. It went into absorb and started charging (voltage both times, before and after restart, were in the 60's).
Now, about 3:30 it is back in bulk mode, the absorb timer shows it never finished (1:38 left). Any idea what is going on here? It's been clear and sunny all day.
Quote from: robbertwilliams on January 19, 2017, 05:56:09 PM
Today, around noon, the CC was in Bulk mode and was not charging (no watts and SOC at 97% where it was a day ago). So, I shut it off and started it back up. It went into absorb and started charging (voltage both times, before and after restart, were in the 60's).
Now, about 3:30 it is back in bulk mode, the absorb timer shows it never finished (1:38 left). Any idea what is going on here? It's been clear and sunny all day.
If you see this again can you take a snap shot of the various MNGP status screens and post them here, even if it takes multiple posts because of size limits. Although I think the limit is now 4000KB not the previous 400KB. Make sure to include the WBjr status pages showing systems amps going into the battery.
Bulk mode and 0 watts sure isn't correct. Resting okay but not Bulk with full sun light on the panels. Do your panels get any shading during the day from surrounding objects? What kind of angle are the panels and what direction are they facing? Are they all the same angle and direction?
BTW don't think I have seen you post the firmware versions of your Classic. Can you also do that.
Thanks
I'll be there all day tomorrow keeping an eye on things.
No shading near noon hour. The panels are all on a DPW top of pole mount. I have them tilted to the second to last hole (approx 60 degrees). The panels are facing true south. The firmware is 2096 (3/23/16).
Quote from: robbertwilliams on January 19, 2017, 07:31:34 PM
I'll be there all day tomorrow keeping an eye on things.
No shading near noon hour. The panels are all on a DPW top of pole mount. I have them tilted to the second to last hole (approx 60 degrees). The panels are facing true south. The firmware is 2096 (3/23/16).
Do you know what the MNGP firmware is at?
There are actually three Classic, MNGP, and Network. The Network version can only be seen on the LA IIRC.
Quote from: robbertwilliams on January 19, 2017, 05:56:09 PM
Today, around noon, the CC was in Bulk mode and was not charging (no watts and SOC at 97% where it was a day ago). So, I shut it off and started it back up. It went into absorb and started charging (voltage both times, before and after restart, were in the 60's).
Now, about 3:30 it is back in bulk mode, the absorb timer shows it never finished (1:38 left). Any idea what is going on here? It's been clear and sunny all day.
Yeah there is just a lot of questions about this. Had it gone into Absorb and then back to Bulk or did it only go to Absorb after you cycled power? Did you see the 0 watts in the Main Status screen? Did you see exactly when it went to 0 watts? Were you using the MNGP at the time?
See what I mean about a lot of questions? This is where all the recorded data from the LA could help in troubleshooting the issue. Sorry I'm not being helpful as I've never seen this before. Seen it resting during the day but not charging in Bulk, no.
This maybe one for boB to comment on.
Agree with John ... Have never seen the Classic stay in Bulk and make 00.00 watts. To be in Bulk, the Buck Converter needs to be running. The Classic will shut off the Converter and go to Resting below about 14 watts of output. Guess that for an instant, perhaps the Classic's output could be 00.00 watts and show bulk, but would be that if that could be the case, it would exist for a second or less.
So,
1. Why not try that other Mode suggested previously -- Legacy P&O?
2. If you happen to see the Classic Resting, in full sun, check the Reason For Resting, RFR, as noted in this Thread:
http://kb1uas.com/mnsforum/index.php?topic=2034.0
3. So, before you added the second string of batteries, how well was that string of batts being charged ... did you measure SGs?
4. Since you did your own conversion of an MNPV3 to MC4 inputs, kind of wonder if there might be some kind of poor connection, or even miswiring that might cause you to have more reasonable PV string voltage than before, but perhaps the PVs cannot supply very much current (due to a poor connection), so the Classic spends much time Resting.
5. Previously, you mentioned some concerns about Shading. You do realize that really ANY shading at all whatsoever, can easily essentially kill ALL PV power production -- a shadow from a cable, a pipe, vent, etc is a real killer. Also any snow, ice etc will do the same.
I had hung my hat on the concern about parallel strings of 60-cell PVs being the culprit.
Did you say that you had a clamp-on DC ammeter? This could allow you to test the Short Circuit current (Isc) of your PVs, which could be quite telling regarding any poor connection issues.
Realize that it might be quite a task to get access to the PVs themselves with your probable weather, but you could do such a test near the input to the Classic, if you DO have a clamp DC ammeter -- a very useful tool, especially when one has multiple strings of batteries.
Have you ever Updated the Firmware on the Classic/MNGP?.
More later ... thinking about this. Vic
Robert ,
If you have an Android - get Grahams Classic App - it is easy to take screenshots and post them .
Or easy to take screen shots of Local Status App too and post those.
It would be good to see some actual photo's of your systems wiring.
Larry
I'll get a bunch of photos today. I'll put them in a Flickr account.
When testing D.C. Amps at the panels, I am getting the same per string as the combined CC reading (2.5/string to 5/CC).
I'm still onlycharging one single string of batteries until this mess of unknowns is cleared up. I'd hate to make it any more complicated.
I'll be running the local app all day today (however, as it has done in the past, it often closes the connection).
Quote from: robbertwilliams on January 20, 2017, 07:22:54 AM
I'll get a bunch of photos today. I'll put them in a Flickr account.
When testing D.C. Amps at the panels, I am getting the same per string as the combined CC reading (2.5/string to 5/CC).
I'm still onlycharging one single string of batteries until this mess of unknowns is cleared up. I'd hate to make it any more complicated.
I'll be running the local app all day today (however, as it has done in the past, it often closes the connection).
Yes my Local Status app also says it looses connnections but others have said that it keeps on logging data in 2 second intervals that you can export.
To test the panels by short circuiting them you would disconnect the positive and negative of the PV panels and then connect them together and put your clamp meter on and see what current reading you get. Just to be clear that means PV panel , positive wire from that , negative wire from PV not connected to anything else until you short those two leads together and take your reading.
I am not sure if Vic meant you can also short circuit test the two in series - with the higher voltage you would get some arcing when touching the leads together so you would have to make sure you only short circuit test once panel at a time. There may be a way to do the series using a breaker to contain the arc but I haven't ever tried that.
Larry
Quote from: robbertwilliams on January 20, 2017, 07:22:54 AM
I'll get a bunch of photos today. I'll put them in a Flickr account.
When testing D.C. Amps at the panels, I am getting the same per string as the combined CC reading (2.5/string to 5/CC).
I'm still onlycharging one single string of batteries until this mess of unknowns is cleared up. I'd hate to make it any more complicated.
I'll be running the local app all day today (however, as it has done in the past, it often closes the connection).
Yeah that disconnect has been a problem with LA & Classic since the beginning hence MN is now trying to go the way of a com box. Only time will tell. Don't think I have ever seen Graham's App disconnect. But I don't know if he is streaming all the data from the Classic at 2 sec resolution to his live graph.
As long as it reconnect by itself it will continue to log data in the background. IIRC I think the icon turns green again when it connects.
I remember only 1 disconnect that did NOT reconnect in the last yr...
Use Graham's APP for monitoring, like right now and
the MN L.App for setting/checking values...
Will load new version later tonight...
Quote from: Westbranch on January 20, 2017, 07:47:02 PM
I remember only 1 disconnect that did NOT reconnect in the last yr...
Use Graham's APP for monitoring, like right now and
the MN L.App for setting/checking values...
Will load new version later tonight...
I don't think you should load that test version of Grahams - it was only to see if that temp comp worked. Seemed like the rest of the app wasn't working quite right so I went back to the playstore version.
Larry
Well, the LA disconnected several times today with only a couple of automatic reconnects (when it had the disconnect window, in the background I could see it in green and the "view" button - however, most of the time that wasn't the case). I was able to export today's numbers and view them in excel. I'm having trouble with the time stamp? How do I format that column so I don't have some weird logarithm?
Here's a link to my flickr pictures taken today. https://flic.kr/s/aHskST1iCQ
I did not do a short circuit test today. It was kind of a gloomy day and overcast. I was able to make it through absorb (4hrs) with the inverter on - lights, radio, etc. So, I've had a couple of days to watch either bank when it's hooked up and charging. The WBjr Amps seems to pretty much level off at 1.5 (this is the number given on the MNGP WB screen along with remaining Ah and SOC). So, if that's the case, that number should work for ending amps if my battery bank is 370ah. When I connect the separate banks for a 740ah, do I double that ending amp number? (This is what I'm remembering to do - ending amps = "approx .10*BBAh")
Nothing too weird today.
Hi,
Quote from: robbertwilliams on January 20, 2017, 09:09:15 PMI was able to export today's numbers and view them in excel. I'm having trouble with the time stamp? How do I format that column so I don't have some weird logarithm?
Look here:
http://kb1uas.com/mnsforum/index.php?topic=3584.msg34394#msg34394
Read that one post, then follow the link, and read the posts there.
dRdoS7
Larry , as far as I can seee you hit the nail.... it showed a temp comp lower than the Absorb V setting.see my comment on Android post.....
Quote from: robbertwilliams on January 20, 2017, 09:09:15 PM
Well, the LA disconnected several times today with only a couple of automatic reconnects (when it had the disconnect window, in the background I could see it in green and the "view" button - however, most of the time that wasn't the case). I was able to export today's numbers and view them in excel. I'm having trouble with the time stamp? How do I format that column so I don't have some weird logarithm?
Here's a link to my flickr pictures taken today. https://flic.kr/s/aHskST1iCQ
I did not do a short circuit test today. It was kind of a gloomy day and overcast. I was able to make it through absorb (4hrs) with the inverter on - lights, radio, etc. So, I've had a couple of days to watch either bank when it's hooked up and charging. The WBjr Amps seems to pretty much level off at 1.5 (this is the number given on the MNGP WB screen along with remaining Ah and SOC). So, if that's the case, that number should work for ending amps if my battery bank is 370ah. When I connect the separate banks for a 740ah, do I double that ending amp number? (This is what I'm remembering to do - ending amps = "approx .10*BBAh")
Nothing too weird today.
Robbert
Thanks for the pictures, haven't reviewed them all yet. But I want to mention that your MNGP firmware is not in sync with you Classic firmware with the picture you show CLASSIC 2096 which you had mentioned before. But it also shows the MNGP at 1933 the MNGP should be at 2054 IIRC. Of course my Classic is to far away to look at but that is what I have in my notes.
Classic 2096 3/26/16, Network 2097, MNGP 2054 8/11/15Sometime there is not an update for the MNGP but if you missed a prior one you need to keep them in sync as that they are all at the latest versions. Things tent to work better that way.
On the LA time data - see my post here http://kb1uas.com/mnsforum/index.php?topic=3137.msg29173#msg29173 (http://kb1uas.com/mnsforum/index.php?topic=3137.msg29173#msg29173)
Are the MNGP photos take from yesterday when you had the no charging in Bulk? Don't know what to say about that other the last VOC was 57.2 and V In was down to 39.4 V . My VOC is around 44 V and I typically see 33-35 V In during Bulk but I'm running 12 V batteries. Let see what Vic thinks about that.
What do you have going on Aux 1 ??
Quote from: robbertwilliams on January 20, 2017, 09:09:15 PM
Well, the LA disconnected several times today with only a couple of automatic reconnects (when it had the disconnect window, in the background I could see it in green and the "view" button - however, most of the time that wasn't the case). I was able to export today's numbers and view them in excel. I'm having trouble with the time stamp? How do I format that column so I don't have some weird logarithm?
Here's a link to my flickr pictures taken today. https://flic.kr/s/aHskST1iCQ
I did not do a short circuit test today. It was kind of a gloomy day and overcast. I was able to make it through absorb (4hrs) with the inverter on - lights, radio, etc. So, I've had a couple of days to watch either bank when it's hooked up and charging. The WBjr Amps seems to pretty much level off at 1.5 (this is the number given on the MNGP WB screen along with remaining Ah and SOC). So, if that's the case, that number should work for ending amps if my battery bank is 370ah. When I connect the separate banks for a 740ah, do I double that ending amp number? (This is what I'm remembering to do - ending amps = "approx .10*BBAh")
Nothing too weird today.
I am looking at the photo of your MNDC box - and not quite following your wiring from the Classic to the small breakers at the bottom right of box. I see what looks like battery positive going from Classic through breaker to the bottom post of the inverter breaker . That sounds good. But what are the two breakers next to it ? It almost looks like a jumper at the top of two of them that tie the two together ? And what is the smaller white wire that looks like it goes from the negative load side of the shunt to one of those breakers ? Maybe it just goes behind them ? So I can't follow the route of the PV positive through a breaker to the Classic . What does the black wire on the grounding buss go to ?
Just looked again - and maybe the PV positive comes in to bottom of middle breaker , then you have that jumped at top to the other breaker and the PV pos to the Classic goes out from bottom of third breaker ? What are the ratings of those breakers ? Not sure why you would be using two breakers there ?
Larry
Hi robbertwilliams,
Thanks for the pics.
Have never seen a Classic in Bulk, making no current output, except for a second, perhaps ...
The RED background in the LA indicates that there is an Error. In the main Status screen there is an Alerts button, which may tell you what is the error.
Also on the center gauge, there is a small rectangle below and to the right of the "MidNite Solar" script, believe that if you clicked on that, the error may also be defined.
More later, Thanks, Vic
Okay looked at the pictures a little more. Here are my comments for what they are worth. :-\
- The color on the LA may have been changed as the Classic Name is shown in RED and the default is Green. I also believe the whole window changes color on Alerts. At least the Main display does. So maybe no Alert.
- The photo of the Array on the pole mount seems to have a shadow across the bottom two panels. May be the way the photo was taken.
- The MNGP photo with the VOC at 57.2 V and V In at 39.4 V seem to be a problem. Don't know how the sweep got down that low unless LOWMAX was still Enabled. And it apparently stuck there. With 0 watts I would have though it would have gone to resting. The next day the LA is showing V IN at 65-69 V at 9:40am. Probably also effected by the temp of the panels, don't know what the VOC at that time was as I think it is on the status-info screen of the LA. I would have gone back to the menu on the MNGP and PRESSED ENTER to see if it would force another Sweep and get a correct reading.Either way this seems to be a problem with the Classic Sweep. If it ever repeats I would report it to MidNite or pm Ryan or boB fo comment.
- On the LA Graphs at 9:40 AM it is putting very little amps into the batteries. So don't know what state the controller was in. If Bulk the curve seems to be flat. An hour earlier at 8:40 AM it was showing maybe a 4 Amp rise. Can't see the Battery voltage maybe 26V. I though the Absorb set point was higher than that. Maybe the batteries where not drawn down the prior night and at Float. Don't know if these batteries are just fully charged or if the Classic just isn't charging much at the time of the photo. Could tell a lot more with the LA Export but those files are too large to post here. Would have to use something like ONE DRIVE, DROPBOX, or GOOGLE DRIVE to post the file. Wish we could post larger files. But that takes more server storage.
On a final note it would be good to see photos of the MNGP and LA on the same day while in Bulk or just after going to Absorb that would be the peak Amps going into the batteries.
Hi, Robbertwilliams,
You have received very good advice here from the user group but I will add my two cents here. When I built my system I undersized it or did not estimate how much I would grow the system and I ended up with two not exactly matched battery banks, my Interstate L-16's were 2 years old and well maintained when I suddenly scored the Rolls-Surettes S-530 L-16's for $20.00 , 3 years old and abused badly. I now have them working well in parallel when I have sustained large loads. My whole secret to success in doing this is I do not parallel the bank's unless absolutely necessary. I run on one system only unless my sustained loads are over 1500-2000 watts or so. I have a large paralleling switch to connect the two systems togather for large loads. In normal operation each classic is charging its own bank. EQ'ing is always done separately. This allows the banks to charge at their own rate and has resulted in a system with incredible capacity as I am only a few miles from that big pond, the Pacific Ocean, and am at the brunt end of days of foul weather. I am easily able to weather 10-15 days of no direct sun and still have reserve for medically nessecary electrical devices that will "always have electricity no matter what"
Secrets of success: careful charting of temperature/specific gravity of each cell of banks, I use a temperature compensated hydrometer as a reference....U.S. Navy WWII Precision hydrometer....as well as a Frias hydrometer, Always test in same situation....same temperature range, etc to normalize readings, and on finding discrepancies, applying corrective action to restore batteries to normal s.o.c as determined by resting (reading s.g. two hours after full charge to float).
Hope that you will find this helpful.
David
Quote from: Resthome on January 21, 2017, 01:17:13 AM
Okay looked at the pictures a little more. Here are my comments for what they are worth. :-\
- The color on the LA may have been changed as the Classic Name is shown in RED and the default is Green. I also believe the whole window changes color on Alerts. At least the Main display does. So maybe no Alert.
- The photo of the Array on the pole mount seems to have a shadow across the bottom two panels. May be the way the photo was taken.
- The MNGP photo with the VOC at 57.2 V and V In at 39.4 V seem to be a problem. Don't know how the sweep got down that low unless LOWMAX was still Enabled. And it apparently stuck there. With 0 watts I would have though it would have gone to resting. The next day the LA is showing V IN at 65-69 V at 9:40am. Probably also effected by the temp of the panels, don't know what the VOC at that time was as I think it is on the status-info screen of the LA. I would have gone back to the menu on the MNGP and PRESSED ENTER to see if it would force another Sweep and get a correct reading.Either way this seems to be a problem with the Classic Sweep. If it ever repeats I would report it to MidNite or pm Ryan or boB fo comment.
- On the LA Graphs at 9:40 AM it is putting very little amps into the batteries. So don't know what state the controller was in. If Bulk the curve seems to be flat. An hour earlier at 8:40 AM it was showing maybe a 4 Amp rise. Can't see the Battery voltage maybe 26V. I though the Absorb set point was higher than that. Maybe the batteries where not drawn down the prior night and at Float. Don't know if these batteries are just fully charged or if the Classic just isn't charging much at the time of the photo. Could tell a lot more with the LA Export but those files are too large to post here. Would have to use something like ONE DRIVE, DROPBOX, or GOOGLE DRIVE to post the file. Wish we could post larger files. But that takes more server storage.
On a final note it would be good to see photos of the MNGP and LA on the same day while in Bulk or just after going to Absorb that would be the peak Amps going into the batteries.
Quote from: Vic on January 21, 2017, 12:15:07 AM
Hi robbertwilliams,
Thanks for the pics.
Have never seen a Classic in Bulk, making no current output, except for a second, perhaps ...
The RED background in the LA indicates that there is an Error. In the main Status screen there is an Alerts button, which may tell you what is the error.
Also on the center gauge, there is a small rectangle below and to the right of the "MidNite Solar" script, believe that if you clicked on that, the error may also be defined.
More later, Thanks, Vic
To Vic and John -
The colors have been changed, so, no alert that I'm aware of.
The photo of the array was taken early in the morning, around 8:00ish am. Just given to show tilt. So, shadows? Probably.
Don't have any clue as to the 0w at bulk, but yes, good observation, I turned LMAX back on (not sure what my reasoning for that was, especially considering I have no clue what it does). And if it happens again, just like I've been asked again and again...I'll take pictures of all the status screens, and maybe some more.
John, spot on...9:40am, very little amps going to the batteries. Well, I'm probably going about trying to dial in a "charge" controller when the batteries I have are already charged. So, I'm assuming these tweaks would be better suited if I could somehow draw down the battery bank a bit more than 2-3%. And the possible 26v, that was due to yesterday's on and off shade (it would go from bulk to absorb, then shade, and back to bulk).
To Larry - the MNDC250 Box is wiring as per the diagram given by MN. http://www.savanasolar.com/media/wysiwyg/69_2.jpg
The breakers are oversized, not sure off hand but may be 30 or 60's (I had ordered them, couldn't return and Civic and Alte solar suggested that since I had the two 20amp breakers at the panels, I could use them inside as just shutoff breakers). Don't quote me on what I'm remembering...I may have gotten a little anal and ordered different ones. And the black wire on the grounding bus is a poorly labeled ground coming from the PV's (when I purchased the wire, only black was available from the LES). Oh, and the jumper wire, the diagram will clear that up. I have the internal CC GF disabled because I'm running an "old school" breaker type on the panel.
No one has said anything about my ending amps? And what do I do if I set my ending amps at what the WBJr shows as the taper off point (when I'm using the local app which is being powered by my router/inverter)...then if I turn the inverter off, like when I'm not there, won't the value be different?
And David, thank you. Ever since Vic, and others, have mentioned my panels being not quite up to the job of charging two banks, I've been thinking of installing some sort of Isolation Switch between the two. I wish I had the forethought to plan out a way to have the inverter charge one set off the generator and the other set off the panels...but that's not the case. So, I was thinking possibly a isolation switch between the banks (keep one as basically a backup, but alternate use between banks when the weather and charging conditions permit just to keep them aging together). You mentioned that you have two charge controllers, I don't think I need to go that route as my situation is a bit different but some of your ideas can be relevant. Let me know if you have anything to say, or anyone else, about the isolation switch. I'm not even sure they have them rated for a bank this large. I just know I've seen such a device when dealing with our VW Bus Campervan, coach/starting battery and an isolation switch in between (in the event one or the other dies you'd just flip the switch).
"No one has said anything about my ending amps? And what do I do if I set my ending amps at what the WBJr shows as the taper off point (when I'm using the local app which is being powered by my router/inverter)...then if I turn the inverter off, like when I'm not there, won't the value be different? "
I am not sure what your question is. The ending amps will only apply when the Classic is charging and in absorb. It is monitoring the system amps ( assuming you have the Shunt setting to WBjr instead of internal ) . So it doesn't matter what the loads are . When you aren't there if the batteries are full then it will see the ending amps sooner and go to Float.
Could you confirm the question earier about if your MNGP and firmware updates are all at the same values ? Perhaps do them all over again with newest firmware , do a VMM , restore your setpoints with Local Status App ( save copy first ) .
This is the screen shot I would like to see when you are charging
(//)
Larry
Like this? https://www.solar-electric.com/basw1300amp.html
Step #1 â€" Record ALL your current settings. Get your firmware in sync, update both the Classic and the MNGP firmware and do a VMM when turning the Classic back on after both updates are complete. Wait at least 2 minute after each update says it is finished before going to the next one.
Step #2 â€" Reset ALL your settings. If you want to know what they all do watch Ryan’s five video for the LA on the MN Web Page. And DISABLE LoMax in Tweaks.
Step #3 â€" Keep your Classic settings the same and just observe and record with the LA for a few days without any changes. Draw your batteries down over night and watch what happens the next clear sunny day. Record how low the Net Amps and SOC went from the night before. On a clear day watch how long it takes to get to absorb set point. Set Absorb time to 4 hours and watch the WB current rise to a peak as Bulk ends and drop while at absorb set point. When the WB amps stop dropping and stay the same record that value and how long it took to get there then set the End Amps to 1 Amp above that. The WBjr measures amps going into battery and doesn’t care about amps being used for loads.
Strap #4 â€" Repeat step #3 for a few days and record any changes to what you observed the previous day including weather conditions.
Step #5- Check the SG level on all battery cells and record after Classic has gone to Float.
To dial this in takes a lot of observing and recording while not making any changes. You’re getting close to understanding off grid solar and battery charging, it’s a long learning curve. Oblivious it’s better to do all this in the summer months when you have more days of sun and the temps are warmer. And yes as the days get warmer and the panels are hotter they will make less power.
Quote from: Resthome on January 21, 2017, 02:12:58 PM
Step #1 â€" Record ALL your current settings. Get your firmware in sync, update both the Classic and the MNGP firmware and do a VMM when turning the Classic back on after both updates are complete. Wait at least 2 minute after each update says it is finished before going to the next one.
Step #2 â€" Reset ALL your settings. If you want to know what they all do watch Ryan’s five video for the LA on the MN Web Page. And DISABLE LoMax in Tweaks.
Step #3 â€" Keep your Classic settings the same and just observe and record with the LA for a few days without any changes. Draw your batteries down over night and watch what happens the next clear sunny day. Record how low the Net Amps and SOC went from the night before. On a clear day watch how long it takes to get to absorb set point. Set Absorb time to 4 hours and watch the WB current rise to a peak as Bulk ends and drop while at absorb set point. When the WB amps stop dropping and stay the same record that value and how long it took to get there then set the End Amps to 1 Amp above that. The WBjr measures amps going into battery and doesn’t care about amps being used for loads.
Strap #4 â€" Repeat step #3 for a few days and record any changes to what you observed the previous day including weather conditions.
Step #5- Check the SG level on all battery cells and record after Classic has gone to Float.
To dial this in takes a lot of observing and recording while not making any changes. You’re getting close to understanding off grid solar and battery charging, it’s a long learning curve. Oblivious it’s better to do all this in the summer months when you have more days of sun and the temps are warmer. And yes as the days get warmer and the panels are hotter they will make less power.
Good advice John - I wish I had it long time ago - would have saved me some trouble !
Only thing I wonder about is won't the system amps level off for awhile and then go even lower to stage where they are over charging the batteries ? How do you get the 1 amp above the lowest ?
Larry
Quote from: ClassicCrazy on January 21, 2017, 06:37:12 PM
Quote from: Resthome on January 21, 2017, 02:12:58 PM
Step #1 â€" Record ALL your current settings. Get your firmware in sync, update both the Classic and the MNGP firmware and do a VMM when turning the Classic back on after both updates are complete. Wait at least 2 minute after each update says it is finished before going to the next one.
Step #2 â€" Reset ALL your settings. If you want to know what they all do watch Ryan’s five video for the LA on the MN Web Page. And DISABLE LoMax in Tweaks.
Step #3 â€" Keep your Classic settings the same and just observe and record with the LA for a few days without any changes. Draw your batteries down over night and watch what happens the next clear sunny day. Record how low the Net Amps and SOC went from the night before. On a clear day watch how long it takes to get to absorb set point. Set Absorb time to 4 hours and watch the WB current rise to a peak as Bulk ends and drop while at absorb set point. When the WB amps stop dropping and stay the same record that value and how long it took to get there then set the End Amps to 1 Amp above that. The WBjr measures amps going into battery and doesn’t care about amps being used for loads.
Strap #4 â€" Repeat step #3 for a few days and record any changes to what you observed the previous day including weather conditions.
Step #5- Check the SG level on all battery cells and record after Classic has gone to Float.
To dial this in takes a lot of observing and recording while not making any changes. You’re getting close to understanding off grid solar and battery charging, it’s a long learning curve. Oblivious it’s better to do all this in the summer months when you have more days of sun and the temps are warmer. And yes as the days get warmer and the panels are hotter they will make less power.
Good advice John - I wish I had it long time ago - would have saved me some trouble !
Only thing I wonder about is won't the system amps level off for awhile and then go even lower to stage where they are over charging the batteries ? How do you get the 1 amp above the lowest ?
Larry
See my graph elsewhere in the thread. Once the Amps roll off it stays about the same and when it is in Float it stays the same until a load comes on or the sun goes down. the reason for picking a value a little above it to assure it triggers the counter to go to Float. The System Amps (WBjr ) is a little noisy and bounces around maybe .5-1 Amp at time. Don't think there would be any battery overcharging as long as you have the correct set point voltage for Float. In Float you don't have hardly any amps goin into the Battery.
Another reason for me is from late June to October we running a Swamp cooler with a 12 VDC motor pulling about 19-20 amps and it's fed with water from the lake with a Sureflow water pump that draws about 10Amps when it kicks on and off you can see little spike in the WBjr readings. Depend on the date of the graph I posted it may or may not be there.
How about a link to a video for a dummies guide to the MNGP? Anyone have one? The more I played around with the MNGP today, I feel that the Whizbang Jr screen has nothing to do with ending amps. I found that the ending amps coincided more with the screen prior, and specifically the left side under "in".
Anyone have a detailed link to what EVERY VALUE given on the MNGP ACTUALLY represents/affects?
Quote from: robbertwilliams on January 21, 2017, 10:20:08 PM
How about a link to a video for a dummies guide to the MNGP? Anyone have one? The more I played around with the MNGP today, I feel that the Whizbang Jr screen has nothing to do with ending amps. I found that the ending amps coincided more with the screen prior, and specifically the left side under "in".
Anyone have a detailed link to what EVERY VALUE given on the MNGP ACTUALLY represents/affects?
Picture would be worth a thousand word of what screens you are referring to. I don't understand what screens you are referring to. If you hold the status button down before letting go it gives a short discription of what is coming on the next display. There are videos showing all different part of the menus. There is no ONE video for everything, it would be 4 hrs long. For the WBjr the manual describes the screen pertaining to it.
http://www.midnitesolar.com/pdfs/Whizbang_manual.pdf (http://www.midnitesolar.com/pdfs/Whizbang_manual.pdf)
For all MN documents http://www.midnitesolar.com/documentIndex.php (http://www.midnitesolar.com/documentIndex.php)
Look under the view video list. Be aware some of the video on the MNGP functions where made before the WBjr firmware was added to the Classic. Along the way boB has posted in the early days many of the hidden button pushes that provide data not normally required by a normal user. An example is the NEW DAY that save the daily data to eprom so you can power off the Classic without losing a day's worth of data because idaily data is only save at 23:59. You will learn these over time. Apparently MN has now seen fit to hire a document control person and hopefully over time these documents will get updated. Good Luck with the learning curve.
This status screen show the amps going into the batteries with out the amps being used for loads.
Thanks John for posting that image from the manual.
That Instantaneous Current IS the current that is flowing into the batteries. This IS the current that is used by the Classic to determine when the set EA has been reached, and Absorb needs to end.
On Status screens that precede the WBjr status screens, the "IN", on the left side should be the power being produced ... will have to go look at an MNGP on an operating Classic to see. Neither the IN or current that is noted on the lower right of the MNGP are good indicators of the actual battery charge current. The output current and the MNGP instantaneous current will be quite close to each other, if there are NO loads on the system, especially when the inverter is OFF.
FWIW, Vic
I know that with WBjr the controller will end absorb at the earlier of >X time or <Y amps. Can it tell if <Y amps is because batteries are full vs panels can't produce >Y amps (shading or clouds)?
Quote from: estragon on January 27, 2017, 06:27:22 PM
I know that with WBjr the controller will end absorb at the earlier of >X time or <Y amps. Can it tell if <Y amps is because batteries are full vs panels can't produce >Y amps (shading or clouds)?
It has to be in absorb for it to stop charging at ending amps. If you had a cloud or shade the voltage would drop and it would go from Absorb back to Bulk so even though it went down in amps that would not be ending amps. So yes it knows in that way.
Larry
No update: Just been working the new set of batteries (discharging/charging). I hope to take new SG readings in a few days when it warms up. Then I plan to hook the two banks up together. But I still haven't gotten an answer to this question...when the banks are paralleled, do I take the standard single bank EA and times it by 2? So, right now my ending amps are at 3.8. If I parallel, so two 370ah banks for a total of 740ah, do I make (a starting point but to be later changed by observation) EA 7.6? Or since they are parallel, still 3.8?
Also, I looked into this battery isolation switch stuff. In doing so I came across this video - kind of cool but I'd like to see what everyone has to say about this.
Video:
https://youtu.be/B4830QsybbM
Blue Seas Website - w/a little better description -
https://www.bluesea.com/products/7610/SI-ACR_Automatic_Charging_Relay_-_12_24V_DC_120A
So, to implement this type of system in my scenario, I currently am using 4/0 cable - which would be kinda hard to work all this into a small area. Would it hurt to down size the wiring for this type of setup?
Hello robbertwilliams,
YES, you would need to multiply the EA value for a single string of batteries, by the number of strings of batteries in parallel. Two parallel strings, multiply the starting EA value by two. This, of course, assumes that the battery charging current will be divided exactly equally between the two strings. This equal division may not always be the case.
Using a battery switch to select between two strings can help one manage the use of two strings, but, one would be mindful that the EA setting would need to be changed when changing from charging a single string, verses charging two strings in parallel, in general.
Would suggest that you try to maintain the largest cable size that you can manage, when adding any battery switch, as this switch addition may well add some cable length, and therefore additional voltage drops.
Vic
Hi I have a problem with charging... My 8 6 volt batteries the = 12 volts will go into absorb in the morning and charge to 100% but then as I use power throughout the day it goes down to 85% and doesn't charge until the next day. How do I get me classic 200 to charge when I am using power throughout the day... can I force it t go to absorb? I have 4 255 watt solar panels... and use only about 15 - 20 amps during the day... I have almost 900 amp hrs available.
Hello roma..,
OK, so you are probably using 8 GC2 batteries, wired as 4 strings of two batteries, for 12 V? Are your batteries Flooded? Flooded batteries have easily-removed caps on top of the batteries.
Please give information about the PVs that you are using -- manufacturer, model number, and how the PVs are wired -- one series string of four, ... or (?).
Need info on your batteries - mfg and model number.
After Absorb is completed, and the Classic goes to Float, if there is sufficient PV power available, the batteries State Of Charge (SOC) should be maintained during Float. Any power above that which is needed to keep batteries fully charged will be supplied by the Classic, unless there is not sufficient power available from the Classic.
When the Classic (CC) has been in Float, and there is insufficient power to maintain the Float voltage, the Classic will show Float - MPPT, and you will notice that the battery voltage will begin to descend, as the battery becomes more and more discharged.
In another Post, you asked about Pg 61 in the Classic 2056 Manual -- the settings in that section apply ONLY to the Classic Lite CCs.
You do NOT have a Classic 200 Lite, right?
What are your settings for Absorb and Float?
If your batteries are Flooded, what is your EQ voltage setting?
What is the Absorb time setting?
Are you using the Battery Temperature Sensor attached on the side of one battery?
Are you using an Ending Amps setting?
What Firmware version is your Classic using?
It is not too common for people to use the Rebulk function of the Classic, but, if you wanted to do additional charge cycles in a single day, the Rebulk voltage could be set to a voltage that is below the Float voltage setting, and you could do additional charge cycles on the battery. Generally this is not needed, and can cause added wear on batteries (IMO). Trying to Rebulk when the CC is in Float - MPPT will do nothing in the way of any additional battery recharging.
There will be additional questions about just how you have your series/parallel battery bank wired, etc, but enough for now.
Thanks for additional information. Vic
Quote from: Resthome on January 21, 2017, 02:12:58 PM
Step #1 â€" Record ALL your current settings. Get your firmware in sync, update both the Classic and the MNGP firmware and do a VMM when turning the Classic back on after both updates are complete. Wait at least 2 minute after each update says it is finished before going to the next one.
Step #2 â€" Reset ALL your settings. If you want to know what they all do watch Ryan’s five video for the LA on the MN Web Page. And DISABLE LoMax in Tweaks.
Step #3 â€" Keep your Classic settings the same and just observe and record with the LA for a few days without any changes. Draw your batteries down over night and watch what happens the next clear sunny day. Record how low the Net Amps and SOC went from the night before. On a clear day watch how long it takes to get to absorb set point. Set Absorb time to 4 hours and watch the WB current rise to a peak as Bulk ends and drop while at absorb set point. When the WB amps stop dropping and stay the same record that value and how long it took to get there then set the End Amps to 1 Amp above that. The WBjr measures amps going into battery and doesn’t care about amps being used for loads.
Strap #4 â€" Repeat step #3 for a few days and record any changes to what you observed the previous day including weather conditions.
Step #5- Check the SG level on all battery cells and record after Classic has gone to Float.
To dial this in takes a lot of observing and recording while not making any changes. You’re getting close to understanding off grid solar and battery charging, it’s a long learning curve. Oblivious it’s better to do all this in the summer months when you have more days of sun and the temps are warmer. And yes as the days get warmer and the panels are hotter they will make less power.
So, if my WBJr levels off at 3.7 while in absorb, I should set my ending amps to 4.7? That would be 1 amp above, or did you mean 1/10 of an amp above?
So, I've given up on waiting to do equalize with the panels...we're living here, and drawing a bank down at night, and then charging back up...blah blah blah. So, I've just bitten the bullet and have done the equalize on both banks (individually - one had 1.5hrs via the PV panels, with an additional 1hr from the generator/charger on equalize -- while the other bank has just received 2hrs on generator/charger equalize).
Question: The old bank of batteries (which has received 2.5hrs of equalize time) had leveled off at 8.8amps (as observed via the WBJr). The new bank of batteries (which has received 2hrs of equalize time) has leveled off to 6.7amps (as observed via the WBJr). So, I want to connect these parallel. Are these equalize ending amps of any significance? Does this show the age of the older batteries? Would the old bank benefit from more equalize time?
Also, if the end result is that the banks are of entirely different "vitals" and I parallel the banks, would I benefit to "mix" the banks (ie. take two from each bank and swap with the other bank)?
Looking to parallel these in the next couple days. It's amazing how much power we take for granted. Going off grid has made my real life experiences in public very different...I can't quite understand why we use so much. I don't even have the mini-fridge plugged in and I'm waking to 75% SOC. Currently, I'm running LED lights, TV for a few hours (energy star 52KWh/year), humidifier (air-o-swiss - 115w'ish'), occasionally an HRV (Heat recovery ventilator - 20 min/hr on low), and modem/routers/combox. It's wild how much people in "real" homes are using every day.
QuoteThe old bank of batteries (which has received 2.5hrs of equalize time) had leveled off at 8.8amps (as observed via the WBJr). The new bank of batteries (which has received 2hrs of equalize time) has leveled off to 6.7amps (as observed via the WBJr).
So, I want to connect these parallel.
To connect batteries in parallel, you need to insure the VOLTAGE is identical. Take the lowest voltage battery, and hook a charger to it, when it's voltage = other bank, at that moment, you connect them (with the marine battery switch on the wall)
If the banks voltages don't match, you will have one bank discharging into the other bank, without the benefit of a long jumper cable (ever seen a melted automotive jumper cable from a low battery to a high battery? ) to add some resistance into the system.
Quote from: robbertwilliams on February 17, 2017, 07:59:17 PM
Quote from: Resthome on January 21, 2017, 02:12:58 PM
Step #3 â€" Keep your Classic settings the same and just observe and record with the LA for a few days without any changes. Draw your batteries down over night and watch what happens the next clear sunny day. Record how low the Net Amps and SOC went from the night before. On a clear day watch how long it takes to get to absorb set point. Set Absorb time to 4 hours and watch the WB current rise to a peak as Bulk ends and drop while at absorb set point. When the WB amps stop dropping and stays the same record that value and how long it took to get there then set the End Amps to 1 Amp above that. The WBjr measures amps going into battery and doesn’t care about amps being used for loads.
To dial this in takes a lot of observing and recording while not making any changes. You’re getting close to understanding off grid solar and battery charging, it’s a long learning curve. Oblivious it’s better to do all this in the summer months when you have more days of sun and the temps are warmer. And yes as the days get warmer and the panels are hotter they will make less power.
So, if my WBJr levels off at 3.7 while in absorb, I should set my ending amps to 4.7? That would be 1 amp above, or did you mean 1/10 of an amp above?
The reason I set my EA slightly higher is because if you look at the 2sec data from the LA for the WBjr you will see that there is a bit of noise in this reading and causes it to jump around a bit. To go to float from absorb at EA it has to stay at the set EA or below for a given period of time (don't recall what that is right now- maybe 30-90 sec?). If one reading jumps higher then the counter has to start all over again. On my system I see around .5 of noise. So I set the EA a little higher so it will always fall below EA setting for the required amount of time to trigger Float.
As always your mileage may vary. So you would have to look and your data and see if and how munch the WBjr reading bounces around. You are going to have to export the data from the LA to see this. Don't believe you will see this looking at the MNGP.
The banks are successfully paralleled. I've been watching EA via the exported LA Excel data and they've been leveling off around 6.9.
Been operating the CC in Legacy Mode and have been getting to this charge (float) point after about 2hrs of charge (8:45-10:45am). My current usage has only been approximately 70ah/night (drains down to about 91% SOC).
Plugged the mini fridge in tonight. Looking forward to seeing how much of a drain tonight/recharge we get tomorrow.
Robbert, I just reread your #1 Post....
6.9 is not very different from where you ended up, good ...,
only the Absorb time has increased IIRC...
so I would expect that your bulk time will increase as a factor of the additional number of Ahrs of use you get from the fridge as might the time needed for Absorb.....
see if you can estimate that and compare to what happens tomorrow or the day after.. good hunting.
I quickly read through the thread and didn't see it so I will mention ENDAMPS can use the CLASSIC AMPS or WBjr AMPS.
If you want it to use the WBjr you need to set ENDAMPS to use SHUNT.
In the BATTERY MENU under ADVANCED where you set the REBULK in the lower left corner it will say "CLASC" or "SHUNT".
Unless it is set to "SHUNT" you are using the CLASSIC's AMPS and that is not good for battery ENDAMPS.
Toggle the choice with the LEFT SOFT KEY. Press ENTER to SAVE.
A little update:
I've been keeping an eye on the EA of the shunt via exporting to excel and checking out the graphs/tables. So, with my battery bank capacity of 740ah and a suggested EA setting of 1% of the 740, that would be 7.4. Well, I currently have it down to 5.7, and it could possibly go a tad lower.
Any thoughts? I think the setting is correct by checking SG's, etc. But it seems a fair bit lower than the suggested starting point. I'm guessing a lower EA finish suggests a healthier bank.
Anyways, all has been good. Again, thanks for all the feedback and the help getting my system set up and the understanding of it.
One thing that's been a bugger is charging with the generator via the SE Conext Inverter/Charger. It kept throwing faults as if I were feeding it triple phase (208v). I found that when the fridge would kick on, there was enough of a voltage drop that it would throw a fault and the generator would kick out (become unloaded) and then start back in again. I now just unplug the fridge, and also have lowered the output amps of the charger to 40a (was 65amp - the max of the charger - seemed to be running the generator hard, and probably not the best for the charger as well).
It is a given that excess energy presented to a battery in the final stages of charge creates heat in the battery. Is your battery temp rising? Also is the batt performing as expected?
I know that my winter setting 1% EA setting may be a bit lower than needed in the summer when I get enough sun hrs and intensity to reach Absorb by 11:00.. but right now the basement is sold enough that I only get about a 1 to 2 degree rise in batt temp at the end of the day... Mind you the interior temps are also rising day to day so that ambient temp and batt temps rise somewhat in sync..
In general the Flooded battery banks in use here, have been running below 1% of C for a number of years. This has been about 0.9% of C, when using the lower end of the recommended Vabs from the battery manufacturer.
IMO, young batteries tend to need a lower Vabs. This factor alone will tend to reduce the required EA. The needed Shunt EA will vary in direct proportion to Vabs. A higher Vabs will dictate a higher EA setting, generally.
There are other factors that will affect the ideal Shunt EA value. One of these additional factors seems to be how deeply the battery is being discharged -- deeper discharge seems to dictate a somewhat higher EA, particularly if deep discharges occur daily.
Shunt EA is a very good approach to manage ending Absorb, on Flooded batteries. But, like most things involvolving batteries, it will not always result in a perfect Absorb time.
Of course, there is also the tradeoff in the amount of time spent in Absorb for each charge cycle, verses EQ frequency, voltage, and duration. You can set EA a bit higher, to shorten the amount of time spent in Absorb, but then one will need to EQ more frequently, and perhaps need to increase EQ time.
With young FLAs, it is good to note the Shunt current value, when near the end of an EQ. This can be used as an indicator of when the EQ has done its job, and on a battery that has Hard Sulfation, but is otherwise relatively healthy, the Shunt current will never diminish to the current value for healthy battery. And, again, the EQ voltage will affect the magnitude of this EQ Finishing current.
All just my opinions, FWIW, Vic
I have searched this thread to see if system balance has been addressed but haven't read all the posts.
The balance between 740 AH of battery and roughly 41A of solar generated current is not a practical balance unless you are content getting most of your power with a generator. If you are going to double your battery bank it will require at least a 3.6KW array to generate enough current to charge a 1480AH battery bank @24 volts at a C/10 rate.
The idea of balance in a RE system is one of the most overlooked fundamentals of system design.
Hi Eric,
This IS a long Thread.
IIRC, the relatively small amount of PV was covered. The battery bank was doubled some time ago, although, again from distant memory, each battery string was being charged individually. Perhaps there was a Marine type battery switch being used, or at least considered.
Robert was peppered with a lotta opinions and info, and it seemed that for much of that, the loop was not closed.
In some regards, during Dakota Winters, there may not ever be enough PV power to avoid a lot of genset run-time.
FWIW. 73, Vic
Quote from: Vic on March 13, 2017, 02:31:56 PM
In general the Flooded battery banks in use here, have been running below 1% of C for a number of years. This has been about 0.9% of C, when using the lower end of the recommended Vabs from the battery manufacturer.
IMO, young batteries tend to need a lower Vabs. This factor alone will tend to reduce the required EA. The needed Shunt EA will vary in direct proportion to Vabs. A higher Vabs will dictate a higher EA setting, generally.
There are other factors that will affect the ideal Shunt EA value. One of these additional factors seems to be how deeply the battery is being discharged -- deeper discharge seems to dictate a somewhat higher EA, particularly if deep discharges occur daily.
Shunt EA is a very good approach to manage ending Absorb, on Flooded batteries. But, like most things involvolving batteries, it will not always result in a perfect Absorb time.
Of course, there is also the tradeoff in the amount of time spent in Absorb for each charge cycle, verses EQ frequency, voltage, and duration. You can set EA a bit higher, to shorten the amount of time spent in Absorb, but then one will need to EQ more frequently, and perhaps need to increase EQ time.
With young FLAs, it is good to note the Shunt current value, when near the end of an EQ. This can be used as an indicator of when the EQ has done its job, and on a battery that has Hard Sulfation, but is otherwise relatively healthy, the Shunt current will never diminish to the current value for healthy battery. And, again, the EQ voltage will affect the magnitude of this EQ Finishing current.
All just my opinions, FWIW, Vic
Hello Robert,
Was ANY of the above of ANY use to you ?? ?
For some of us, it can be a bit disappointing to spend 15, or more minutes composing a Post, and receive NO feedback at all whatsoever.
This can result in some folks who try to help members here, becoming convinced that our efforts to help, are of NO use to you whatsoever.
I am finally getting the message ... am a bit slow.
Just trying to give some feedback. Perhaps this is a bit of a sharp comment.
Good Luck !! All the best, Vic
Vic -
Yes, a bit sharp, and yes, a bit useful. I don't think I've ever read anything you have posted that wasn't useful or of value to me. Thank you!!
I guess you could say I've been spread a bit thin - and this forum/thread had only sent me 'new post' notifications via email for the first 2 or so pages. So, from there on out, it's up to me to manually go and check out this forum, which is not part of my daily routine.
Not sure if any of you are familiar with Maslow's Hierarchy of Needs? Well, as selfish as I might seem, I haven't hit the pinnacle of 'Self Actualization'; I'm still building my foundation.
Again, I DO APPRECIATE your 15 minute long's work to type/formulate a worthy post.
Maslow's, ha, have not heard that spoken of since I did my health science degree :o ;D
I see it (Maslow's) every day in my mixed breed Chow/Border Collie... no need to remember who is at the top and self actualized!
The Hemp oil ( not from MJ) for his creaky bones helps actualize him too
Hi Robert,
Thanks for returning.
Good Luck with the off-grid power system. Vic
Found this thread and read most of it .... I noticed the OP has an Schneider Conext SW Inverter/Charger. I am having a hard time getting my SW 4024 to finish a charge for my Trojan L16 435 amp hour batteries (x4 in series) . I get to an SG of 1.266-76 (depending on the cell) and the Classic says I am at 99% SOC with only 433 amp hours. Trojan says 100% is 1.277 and when I did an EQ last week, I noted the SG in all cells stopped rising between 1.286 and 1.295 according to my Hydro, so I took the average of those hi numbers and have tried to use that as a target for 100% charged (because my hydro may be off).
I have raised the Absorb timer to max so it is not timing out ... and have raised the Absorb voltage to 31.2 and temp comp to -5 (so today they were charging at 31.5 +/-). That is getting near EQ voltage. :o
So I was wondering, the SW does not have an end amp setting like the classic. BUT it does ask for the Battery Bank Capacity in Amp Hours. I cannot see a reason why the SW would need to "know" the amp hours (it does not report SOC) except to set End Amps. I did kinda confirm that is the case noting that the charge seemed to kick to float from absorb at about 8.7 amps which equals 435 ah x 2%. So I tried setting the AH in the SW to 100 and it ended at about 4.5 amps. But the batteries were already about 99% charged.
So to the OP .... have you had any experience now since last spring with the SW and charging?
I ask here not to hijack this thread ... or resurrect an old thread (only to get a response from the OP) I am starting a new thread here (http://midniteftp.com/forum/index.php?topic=3948.0).