Are not described in Classic 150 Manual. What are these recommendations for
Absorb Minimum time in minutes,
Absorb Maximum time in minutes,
Equalize time in minutes,
Equalize time intervals,
and what are those battery 1, 2, and 3 you are referring to for flooded type?
What happens if I do not set these values?
Also, how does Classic know when is my BB 100% so it can switch to float. Where do I set that Voltage value? In my case that would be 38.22V according to Trojan.
Thanks!
Quote from: sigp2101 on June 21, 2016, 03:47:44 PM
Are not described in Classic 150 Manual. What are these recommendations for
Absorb Minimum time in minutes,
Absorb Maximum time in minutes,
Equalize time in minutes,
Equalize time intervals,
and what are those battery 1, 2, and 3 you are referring to for flooded type?
What happens if I do not set these values?
Also, how does Classic know when is my BB 100% so it can switch to float. Where do I set that Voltage value? In my case that would be 38.22V according to Trojan.
Thanks!
Hi sigp..,
You will need to Update the Firmware in your Classic, if it has Menu settings for Max AND Minimum Absorb times. The Firmware in your Classic appears to be a number of years out of date.
What is the Firmware version number for the Classic and the MNGP, if your Classic has the LCD display with buttons?
Have you ever updated the Firmware on any Classic?
The Absorb time required to recharge batteries depends mainly, upon the Depth Of Discharge (DOD) that the battery bank experienced in the previous discharge cycle.
The Absorb voltage is set in the Charge > Volts menu. The EQ and Float voltages are also set on that same menu page.
The Classic "knows" to stop charging in the Absorb stage, based upon the time that is set in the Charge > Time menu page. There is also an optional device that allows measuring the battery charge current into the battery bank (the Whizbang Junior + a Shunt) that allows ending Absorb, based upon the charge current to the battery, OR if the Absorb timer has counted down to zero.
Consult the manufacturer of YOUR batteries for recommendations on all voltage requirements, as well as the frequency and duration for any EQs.
Are your batteries Flooded Lead Acid (FLA)? FLAs will need EQs, usually based on a certain length of time, or for some batteries, based on the amount of variation in the Specific Gravity (SG) measurements between each cell in the battery bank.
Am not certain just what is meant by battery 1, 2 and 3 is referring to ... have not seen this in any manual for Classics.
Does any of this help? Vic
Vic, &. sig2101
Those battery types 1,2, & 3 appear in early manuals referring to the MNLP display on the Classic lite.
They are the options with the non graphical display type used in the lite.
There are 7 entries total 1 for gel , 2 for sealed and 3 for FLA. And one for custom as set with external software.
The lite does not allow exact setting of charge points, you must use one of the built in profiles or use external software to set to a custom value.
This is totally non revelant in the full Classic
Sig2101,
I assume that you do have a Classic 150..... NOT a Classic Lite.
The Classic lite does not have a setup for 36 volt battery bank.......must be done as custom
David
Quote from: tecnodave on June 21, 2016, 08:21:06 PM
Vic, &. sig2101 ...
Those battery types 1,2, & 3 appear in early manuals referring to the MNLP display on the Classic lite ...
David
Hi David,
OH !!, had noted that sigp2101's Signature mentioned a "Classic 150", so was not thinking at all about a Classic Lite. Have not ever touched a Lite, or even seen one. So, have not paid much attention to the details of configuring them, and avoid trying to address any questions about setting up one.
As you noted, perhaps sigp2101 has noticed those references to the Lite in a manual, but was unaware of just how a Lite differs from the Standard Classic.
Dunno, but thanks David for adding some clarity to the situation.
Vic
Hi Vic,
first of all thank you for writing back, appreciated!
I will start with little background. CC is Classic 150 purchased in February this year. Serial number is #CL 27075. Firmware I do not know yet since it is at remote location I will get to it this weekend. BB is 6X6V Trojan 105 in 36V configuration. As I was going through manual I was using Classic 150 available on your web for download. Now to address some of your questions.
Quote from: Vic on June 21, 2016, 08:00:13 PM
Hi sigp..,
You will need to Update the Firmware in your Classic, if it has Menu settings for Max AND Minimum Absorb times. The Firmware in your Classic appears to be a number of years out of date.
What is the Firmware version number for the Classic and the MNGP, if your Classic has the LCD display with buttons?
Have you ever updated the Firmware on any Classic?
No, didn't have a chance to do that yet.
QuoteThe Absorb time required to recharge batteries depends mainly, upon the Depth Of Discharge (DOD) that the battery bank experienced in the previous discharge cycle.
How does classic knows about that?
QuoteThe Absorb voltage is set in the Charge > Volts menu. The EQ and Float voltages are also set on that same menu page.
I would like classic to bulk charge as soon as battery bank drops to 50% and to stay that way till it is 80%. At 80 SOC I want it to switch to absorb till 99% SOC and then switch to float for the rest of the sunny day. How do I set my Classic to do just that? There is only absorb and float in charge many + EQ setting.
QuoteThe Classic "knows" to stop charging in the Absorb stage, based upon the time that is set in the Charge > Time menu page. There is also an optional device that allows measuring the battery charge current into the battery bank (the Whizbang Junior + a Shunt) that allows ending Absorb, based upon the charge current to the battery, OR if the Absorb timer has counted down to zero.
I do not have Whizbang. How do I set time, what is the value here for time.
QuoteConsult the manufacturer of YOUR batteries for recommendations on all voltage requirements, as well as the frequency and duration for any EQs.
I did, Trojan specify Bulk, Float and EQ voltage, Classic has EQ, Absorb and Float as set-able variables in CHARGE menu. There is disconnect somewhere.
QuoteAre your batteries Flooded Lead Acid (FLA)? FLAs will need EQs, usually based on a certain length of time, or for some batteries, based on the amount of variation in the Specific Gravity (SG) measurements between each cell in the battery bank.
Yes they are Flooded Lead Acid Trojan T150 GC2 batteries. Thanks!
QuoteAm not certain just what is meant by battery 1, 2 and 3 is referring to ... have not seen this in any manual for Classics.
PAge 58 of this manual - http://www.midnitesolar.com/pdfs/classic_manual_Rev_1933.pdf
This is the one I downloaded since mine is at the remote location along with CC
QuoteDoes any of this help? Vic
Tremendously, as you can all see I am total rookie here trying to put my system together. Last weekend I put it together and did quick start and accepted all default values and left. This coming weekend I want to continue tweaking whole setup and that is why I downloaded manual of the line start reading through it but lots of questions start to pop up.
THANKS a lot for all of your guys dedications.
SIGP2101
Quote from: tecnodave on June 21, 2016, 08:21:06 PM
Vic, &. sig2101
Those battery types 1,2, & 3 appear in early manuals referring to the MNLP display on the Classic lite.
They are the options with the non graphical display type used in the lite.
There are 7 entries total 1 for gel , 2 for sealed and 3 for FLA. And one for custom as set with external software.
The lite does not allow exact setting of charge points, you must use one of the built in profiles or use external software to set to a custom value.
This is totally non revelant in the full Classic
Sig2101,
I assume that you do have a Classic 150..... NOT a Classic Lite.
The Classic lite does not have a setup for 36 volt battery bank.......must be done as custom
David
THANKS! that explains it.
SIGP2101
Quote from: Vic on June 22, 2016, 12:52:15 AM
Quote from: tecnodave on June 21, 2016, 08:21:06 PM
Vic, &. sig2101 ...
Those battery types 1,2, & 3 appear in early manuals referring to the MNLP display on the Classic lite ...
David
Hi David,
OH !!, had noted that sigp2101's Signature mentioned a "Classic 150", so was not thinking at all about a Classic Lite. Have not ever touched a Lite, or even seen one. So, have not paid much attention to the details of configuring them, and avoid trying to address any questions about setting up one.
As you noted, perhaps sigp2101 has noticed those references to the Lite in a manual, but was unaware of just how a Lite differs from the Standard Classic.
Dunno, but thanks David for adding some clarity to the situation.
Vic
Thanks both!
SIGP2101
Hi SIGP..,
From this Page on the MN Solar site, you could find the latest Classic Manual -- for FW 2056:
http://www.midnitesolar.com/documents.php?productCat_ID=21&productCatName=Charge+Controllers+-+Classics&model=CLASSIC 150&product_ID=256&act=
It is not possible to know just what version of FW your Classic is using, but it might be good to have a copy of the latest Manual.
You may not need to Update that Classic.
Do you have Internet access at the site where the Classic is located?
Thanks, Vic
In regards to having a CC start a charge cycle, based upon State Of Charge (SOC), I do not know how to make any CC do that.
The later versions of Classic Firmware (FW), have a Skip Days function, in the Advanced charge menu, but this just skips a number of days that you set.
Generally, the user of the system needs to monitor SOC (as shown by SG readings, for Flooded batteries), and manually change CC settings to achieve as close to the desired results as is possible.
Remote sites can be a bit difficult to manage, especially if those sites have varying Depth Of Discharge (DOD), from one day to the next. With Flooded batteries, this is not such a large issue, as Flooded batteries are quite forgiving of a bit of overcharge, and some undercharge, if this undercharge is not chronic, and so on ...
You might want to study the benefits of adding the WhizBang Junior and a 50 mV Shunt to your system. These, together will allow you to monitor the actual battery charge current, and the WBjr can tell the Classic to switch from Absorb, to Float, based on the actual battery Finishing current, also called End Amps (EA).
WBjr at a reliable reseller:
http://www.solar-electric.com/midnite-solar-whiz-bang-jr-current-sense-module.html
A good 50 mV Shunt:
http://www.solar-electric.com/mkb-500-50.html
FWIW, Vic
Quote from: Vic on June 22, 2016, 01:09:08 PM
Hi SIGP..,
From this Page on the MN Solar site, you could find the latest Classic Manual -- for FW 2056:
http://www.midnitesolar.com/documents.php?productCat_ID=21&productCatName=Charge+Controllers+-+Classics&model=CLASSIC 150&product_ID=256&act=
It is not possible to know just what version of FW your Classic is using, but it might be good to have a copy of the latest Manual.
That is the one I have
QuoteYou may not need to Update that Classic.
Good
Quote
Do you have Internet access at the site where the Classic is located?
Thanks, Vic
Unfortunately totally off the grid, no Internet yet. Maybe one day with satellite link.
QuoteIn regards to having a CC start a charge cycle, based upon State Of Charge (SOC), I do not know how to make any CC do that.
I do not understand, what is the point of having all this settings for Absorb, Float, EQ when CC can't sense when BB reach those crucial setting points?
What you are saying is that CC keeps charging regardless of SOC. Am I missing something here?
Thanks!
SIGP2101
Quickly,
For most of our history, off-grid systems attempted to have PVs fully charge batteries EVERY day. Flooded batteries can take some overcharge. Some undercharge on some days is OK, due to weather conditions, etc, as long as the battery gets fully-charged several times per week.
If that does seem like the correct approach to you, the Classic is the only CC that I know of, that has the Skip Day function. This allows YOU to set the number of days the you estimate that will reach the DOD that is good for your system, and only charge one day, and then Skip that same number of days, again, and so on.
There are some projects that some users of MidNite CC are working on, for additional monitoring and control functions ... so if you are interested in Programming some external computer CC controlling and monitoring gadgets, there are several of those listed it their own section of this Forum.
This topic area is called, " The Open Source software/hardware corner ". I am not actively doing any of these types of monitor and control functions at this time, so I am of no help.
Later, Vic
Quote from: Vic on June 22, 2016, 03:29:52 PM
Quickly,
For most of our history, off-grid systems attempted to have PVs fully charge batteries EVERY day. Flooded batteries can take some overcharge. Some undercharge on some days is OK, due to weather conditions, etc, as long as the battery gets fully-charged several times per week.
If that does seem like the correct approach to you, the Classic is the only CC that I know of, that has the Skip Day function. This allows YOU to set the number of days the you estimate that will reach the DOD that is good for your system, and only charge one day, and then Skip that same number of days, again, and so on.
There are some projects that some users of MidNite CC are working on, for additional monitoring and control functions ... so if your are interested in Programming some external computer CC controlling and monitoring gadgets, there are several of those listed it their own section of this Forum.
This topic area is called, " The Open Source software/hardware corner ". I am not actively doing any of these types of monitor and control functions at this time, so I am of no help.
Later, Vic
Thanks a bunch!
The Challenge for me then is to find best configuration settings for my off-grid weekend cottage. I will be running few lights and small fridge (up to max 1KW per day) but only during weekends. Occasionally will be extended stays up to 5 days. Any suggestions?
Quote from: sigp2101 on June 22, 2016, 05:59:05 PM
Thanks a bunch!
The Challenge for me then is to find best configuration settings for my off-grid weekend cottage. I will be running few lights and small fridge (up to max 1KW per day) but only during weekends. Occasionally will be extended stays up to 5 days. Any suggestions?
[/quote]
Hi sigp..,
OK, so when you are not at your cabin, the fridge is not running, correct?
And, do you leave your inverter running during your absence?
Are there ANY loads running when you are absent from the cabin?
Without knowing quite a bit about your system, like type and amount of PV or other charging power available on an average day, average loads when you are at the cabin, etc, etc ...
A battery that is lightly discharged may well only need about an hour of Absorb, at a reasonable Absorb voltage. More deeply discharged, probably a longer Absorb.
And, as an aside, even the best Battery Monitoring devices available are not terribly accurate, in an absolute sense. It is nearly impossible to make a very accurate model of the way batteries behave, as Ah Capacity remaining depends on just how, and at what rate the energy happened to have been removed from the battery, and just how that battery happens to be recharged, and so on.
So, IMO, the reported SOC and Ah remaining shown by essentially any battery monitoring device is really, just a fairly rough estimate. Not a bad approximate guide to SOC and Ah remaining, just not that exact, on average. Therefore trying to wait to recharge a battery when it is at 50% SOC, could, possibly disappoint.
For systems using Flooded batteries, with very regular discharge and charge patterns, there is a better chance that the user of the system can monitor the SGs of the battery, and do a better job in setting the important battery parameters into the battery monitoring device ...
Just my opinion, FWIW, Vic
QuoteHi sigp..,
OK, so when you are not at your cabin, the fridge is not running, correct?
Correct
QuoteAnd, do you leave your inverter running during your absence?
All is disconnected except CC.
QuoteAre there ANY loads running when you are absent from the cabin?
NO
QuoteWithout knowing quite a bit about your system, like type and amount of PV or other ...
Panels are 3 X 235W 36V 8A SolarWorld
sigp2101,
Thanks for the info on your system.
So, you are running the three SW-235 PVs in series, for a String Vmp of about 90-ish volts (at STC) to the Classic, assumed.
With absolutely no loads on the batteries, except the Classic itself, you could expect to run a number of weeks with no charging at all.
In your absence, you could Float the batteries at the suggested Float voltage. Or, even Float at a somewhat reduced Vfloat. Some of the strategy depends upon just how long will your absence be.
You could set a number of Skip Days, and do a full, or partial charge on the charge day.
Looks kind of like you have the batteries and inverter in a Root Cellar type of location. This is often a very good idea, as it does moderate the range of temperatures experienced by the batteries. There can be considerations of how to deal with low temperatures in Winter, in the Northern climes, where there is some risk of freezing the batteries and ruining them.
You will become more familiar with the way your system operates, and how your charge strategy is working, as, when you return you can check the SGs when you first arrive.
Vic
Quote from: Vic on June 23, 2016, 01:00:16 AM
sigp2101,
Thanks for the info on your system.
Please do not thank me, THANK YOU for such unselfish support for my project.
QuoteSo, you are running the three SW-235 PVs in series, for a String Vmp of about 90-ish volts (at STC) to the Classic, assumed.
Correct!
QuoteWith absolutely no loads on the batteries, except the Classic itself, you could expect to run a number of weeks with no charging at all.
That is very encouraging, ultimate goal is to eventually be able to leave fridge run over summer months mostly.
QuoteIn your absence, you could Float the batteries at the suggested Float voltage. Or, even Float at a somewhat reduced Vfloat.
And to do that I assume I will have to set all voltages to float desired level. absorb = float. Correct?
THANKS!
Quote from: sigp2101 on June 23, 2016, 09:11:54 AM
Quote from: Vic on June 23, 2016, 01:00:16 AM
sigp2101,
QuoteIn your absence, you could Float the batteries at the suggested Float voltage. Or, even Float at a somewhat reduced Vfloat.
And to do that I assume I will have to set all voltages to float desired level. absorb = float. Correct?
THANKS!
No, you would set Skip DAYS to the number of days you want the CC/Batteries to only go to Float set point. Once that number of days is met it will charge you batteries with Bulk-Absorb-Float set point and the following day start the Float only cycle again.
Really recommend you add the WBjr and Shunt to you system so you can use END AMPS to terminate Absorb rather than a set amount of time.
Oh wait someone said you had a light, you would have to program this from a computer with the Midnite Local Staus App. Also suggest you invest in the MNGP which provides a lot of control over the Midnite CC
Quote from: Resthome on June 23, 2016, 02:50:26 PM
Oh wait someone said you had a light, you would have to program this from a computer with the Midnite Local Staus App. Also suggest you invest in the MNGP which provides a lot of control over the Midnite CC
Plan is to have light in my cottage, that is why I am doing all this.
I do have MNGP it came with Classic 150. That is how I will do all programing on CC.
Quote from: sigp2101 on June 23, 2016, 09:11:54 AM
Quote from: Vic on June 23, 2016, 01:00:16 AM
sigp2101,
Thanks for the info on your system.
Please do not thank me, THANK YOU for such unselfish support for my project.
QuoteSo, you are running the three SW-235 PVs in series, for a String Vmp of about 90-ish volts (at STC) to the Classic, assumed.
Correct!
QuoteWith absolutely no loads on the batteries, except the Classic itself, you could expect to run a number of weeks with no charging at all.
That is very encouraging, ultimate goal is to eventually be able to leave fridge run over summer months mostly.
QuoteIn your absence, you could Float the batteries at the suggested Float voltage. Or, even Float at a somewhat reduced Vfloat.
And to do that I assume I will have to set all voltages to float desired level. absorb = float. Correct?
THANKS!
Hi sigp..,
First, just to try to be clear. There is a Classic Lite -- the Lite is the Classic without the MNGP, it has only some switches and LEDs.
You DO have the MidNite Classic 150 with the MNGP. This is very good.
If you would want to run a fridge in the Summer in your absence, things become less certain. One would need to know the amount of energy that the fridge uses in a typical day, the amount of Solar Insolation (in kWh per day) for the months that the fridge would need to run, and so on. One would need to know your approximate location, and the nature of any shading of the PVs from trees, hills, etc.
I become a bit reluctant to give much advice on setting up systems that will be unattended for a period of time. The longer the period of absence, the more difficult the situation can become.
If there are essentially no loads on the batteries during the absence, the power system is much more predictable than if there are varying loads, like a fridge.
If one has considerable battery Capacity, and significant PV power available, the risks to unattended systems us really quite small.
Today was a transit day, will try to catch up on any other of your other Posts.
More Later, Vic
Quote from: Vic on June 23, 2016, 07:52:51 PM
Hi sigp..,
First, just to try to be clear. There is a Classic Lite -- the Lite is the Classic without the MNGP, it has only some switches and LEDs.
You DO have the MidNite Classic 150 with the MNGP. This is very good.
Quote
If you would want to run a fridge in the Summer in your absence, things become less certain. One would need to know the amount of energy that the fridge uses in a typical day, the amount of Solar Insolation (in kWh per day) for the months that the fridge would need to run, and so on. One would need to know your approximate location, and the nature of any shading of the PVs from trees, hills, etc.
I have fridge and its power rating is only 159Kw per year. That is bit over 400 Watts in 24 hours period according to simple calculations. I was conducting test last weekend using http://www.homedepot.com/p/Kill-A-Watt-Electricity-Monitor-P4400/202196386 (http://www.homedepot.com/p/Kill-A-Watt-Electricity-Monitor-P4400/202196386) and reading was 0.17 KWh in 25 hours. I will also have up to 50W LED lights and laptop. That is it that is all.
Location is 45.9 and insolation is 4 hours summer 2 hours winter. No shading during these hours.
Quote
Today was a transit day, will try to catch up on any other of your other Posts.
More Later, Vic
Thanks so much again and there is no rush ever. I come here for bit of the knowledge at the time, and then go and try to apply it over the weekend.
Quote from: Vic on June 21, 2016, 08:00:13 PM
The Absorb time required to recharge batteries depends mainly, upon the Depth Of Discharge (DOD) that the battery bank experienced in the previous discharge cycle.
Does this mean that I will have to manually monitor DOD of my batteries every day and set absorb time for the next day?????
Quote
The Classic "knows" to stop charging in the Absorb stage, based upon the time that is set in the Charge > Time menu page.
Assuming I set it up right the previous day. Right???
That was original intention of this thread to find out to what value to set time parameter. I am still confused and do not know answer to this I feel very important question. What happens if Time parameter is left at default value 00:00. Will classic charge BB at all?
Hi sigp..,
If your loads are quite similar every day, a fixed Absorb time can work well. You will just need to determine what is that value, experimentally.
Flooded batteries are very forgiving, AND, trying to err a bit on the side of a bit of overcharge, verses a bit of undercharge each day.
But, if your loads vary considerably every day, a fixed Absorb time does not work so well. It is all a matter of degrees. For systems with reasonably large amounts of PV power available, and reasonably large battery Capacity relative to daily discharge of the batteries, NOT charging every day can be a good approach. Am not certain that your system quite qualifies as such a system.
IIRC, you do NOT have the WhizBangJr battery current sensing module. The WBjr would allow your system to terminate Absorb, based on the Return Current (End Amps). And, it alloys you to accurately measure the actual battery charge current with very good precision, all you would need is a 50 mV/500 A Shunt and the WBjr. This has a cost of about U$D 100, including a bit for shipping if you are in North America.
As mentioned before, we have always used End Amps -- first it was just EA based on the CC's output current. The Outback MX-60 allowed this. With the Classic CC and the WBjr, it is quite inexpensive to end Absorb using actual battery charge current, allowing the ability of generally being able to ignore the system loads on the inverter. Shunt EA is a very good way to end Absorb at an appropriate time on systems with relatively large and intermittent loads.
Does this make sense to you? Am NOT trying to sell hardware, however. FWIW, Vic
Quote from: Vic on July 15, 2016, 02:36:59 PM
Hi sigp..,
If your loads are quite similar every day, a fixed Absorb time can work well. You will just need to determine what is that value, experimentally.
Flooded batteries are very forgiving, AND, trying to err a bit on the side of a bit of overcharge, verses a bit of undercharge each day.
But, if your loads vary considerably every day, a fixed Absorb time does not work so well. It is all a matter of degrees. For systems with reasonably large amounts of PV power available, and reasonably large battery Capacity relative to daily discharge of the batteries, NOT charging every day can be a good approach. Am not certain that your system quite qualifies as such a system.
IIRC, you do NOT have the WhizBangJr battery current sensing module. The WBjr would allow your system to terminate Absorb, based on the Return Current (End Amps). And, it alloys you to accurately measure the actual battery charge current with very good precision, all you would need is a 50 mV/500 A Shunt and the WBjr. This has a cost of about U$D 100, including a bit for shipping if you are in North America.
As mentioned before, we have always used End Amps -- first it was just EA based on the CC's output current. The Outback MX-60 allowed this. With the Classic CC and the WBjr, it is quite inexpensive to end Absorb using actual battery charge current, allowing the ability of generally being able to ignore the system loads on the inverter. Shunt EA is a very good way to end Absorb at an appropriate time on systems with relatively large and intermittent loads.
Does this make sense to you? Am NOT trying to sell hardware, however. FWIW, Vic
I like idea of terminating Absorb charge based on EA since my system will be very stable between weekends. Meaning no loads at all. Now, how do I figure the EA number.
sigp..,
OK but with NO loads at all, there will only be the self-discharge of the battery to think about. This discharge is temperature-dependent. But should not exceed about 5% per week ... something like that with the Inverter OFF, and the Classic's input and battery breakers OFF.
If the above is the case, you cannot charge, of course, but you would have several weeks of off time before you would need to be concerned about charging the batteries.
Know, that you had wondered about running the refer during summer months, and this would, of course, would be a different matter altogether.
Determining the proper EA value with Flooded batteries is relatively simple. With stable and light loads on the system, set a long Absorb time, let's say 360 minutes. Watch the CC's output current during Absorb. As absorb progresses the output current of the CC will taper, to a lower and lower value. When this value does not change for about 20 minutes, or so, this is a good beginning start for YOUR EA. You can measure the SGs of the battery to confirm that this is in the ballpark. Reset the long Absorb time to a reasonable value.
But, without the WBJr, if the loads on the system increase, the Absorb might not ever terminate, based upon EA. But the time set for Absorb will be the thing that will end Absorb, in this case, so using a reasonable value there should be a good backup to EA.
One other thing. The EA setting required will need to be changed if you choose to change the Absorb voltage -- if you raise the Vabs, the EA value will probably need to be increased, and if the Vabs is lowered the EA value may need to be reduced. If you are only making one or two tenths of a volt change Vabs, EA may not need to be changed.
Enter your Vabs, Absorb times, and EA values in your Battery Logbook. This will help you track the effects of changes upon battery SGs.
None of this need be perfect, as you have Flooded batteries and your trusty Hydrometer, so you can actually measure how well charged that batteries actually are.
FWIW, Vic
Quote from: Vic on July 15, 2016, 03:57:29 PM
sigp..,
OK but with NO loads at all, there will only be the self-discharge of the battery to think about. This discharge is temperature-dependent. But should not exceed about 5% per week ... something like that with the Inverter OFF, and the Classic's input and battery breakers OFF.
If the above is the case, you cannot charge, of course, but you would have several weeks of off time before you would need to be concerned about charging the batteries.
Know, that you had wondered about running the refer during summer months, and this would, of course, would be a different matter altogether.
Determining the proper EA value with Flooded batteries is relatively simple. With stable and light loads on the system, set a long Absorb time, let's say 360 minutes. Watch the CC's output current during Absorb. As absorb progresses the output current of the CC will taper, to a lower and lower value. When this value does not change for about 20 minutes, or so, this is a good beginning start for YOUR EA. You can measure the SGs of the battery to confirm that this is in the ballpark. Reset the long Absorb time to a reasonable value.
But, without the WBJr, if the loads on the system increase, the Absorb might not ever terminate, based upon EA. But the time set for Absorb will be the thing that will end Absorb, in this case, so using a reasonable value there should be a good backup to EA.
One other thing. The EA setting required will need to be changed if you choose to change the Absorb voltage -- if you raise the Vabs, the EA value will probably need to be increased, and if the Vabs is lowered the EA value may need to be reduced. If you are only making one or two tenths of a volt change Vabs, EA may not need to be changed.
Enter your Vabs, Absorb times, and EA values in your Battery Logbook. This will help you track the effects of changes upon battery SGs.
None of this need be perfect, as you have Flooded batteries and your trusty Hydrometer, so you can actually measure how well charged that batteries actually are.
FWIW, Vic
Hi Vic,
Thanks for long explanation, everything is starting to make sense now. All these little tweaks are what is needed. Your input is of tremendous help.
One more question, how do I go about setting to skip two days in the row but I want those two days to fall on weekend?
SIGP2101