I have a Classic 200 with 8 ea 300W panels of 35.7 volts going through a combiner and into the classic. It is currently clicking...apparently at the relay...and the screen says "resting." This lasts for only a few seconds and then it resorts back to Bulk MPPT. When it went to float, of course the clicking stopped and 0.00 amp coming in. It was doing this at 2 pm when there is full sun. I noticed that it did this the other evening as the sun was beginning to go down. In my mind, it should not have gone to "rest" at that point but I thought maybe the sun angle was less than necessary to do any absorb or float. Does this mean the relay is going bad? If so, what would I need to do? If not, any ideas? I hope I have given enough info.
What is the battery bank voltage? Any shadows on PVs? What is the PV Voltage going into the Classic? What are your Absorb and Float voltage settings?
Battery bank voltage is 24V and 938 aH when fully charged. At 2 pm, there are no shadows at all. I am in the SE of US and today was
clear and bright. Float is set at 26.5 and Absorb at 31.5. This is a forklift battery so I've had to increase the absorb voltage. Things have performed well in the past, so this is why I am concerned. PV in varies, of course.
Quote from: elesaver on April 13, 2016, 06:59:53 PM
Battery bank voltage is 24V and 938 aH when fully charged. At 2 pm, there are no shadows at all. I am in the SE of US and today was
clear and bright. Float is set at 26.5 and Absorb at 31.5. This is a forklift battery so I've had to increase the absorb voltage. Things have performed well in the past, so this is why I am concerned. PV in varies, of course.
That is a high absorb voltage for a 24v bank. I run deep folk lift battery at 12v and the max I run is 14.7v + temp comp. You are running an Equalize voltage. Okay so PV varies. I am assuming you normally reaching float each day, not sure if you are using a WBjr with end amps or are timing Absorb.
What PV voltage is it showing at the time you see it going to REST?. What are the spec on the panels and how do you have them connected? I'm looking at what the total Vmp would be. You got 2400 watts of power and I assume the 35.7v is for one panel. Make and model of the panels is always helpful. Also what version of the firmware are you running. If you have the MNGP can you also capture the Reason for Resting when you see it resting. That number could tell a lot.
To get Reason For Resting (RFR), go to the main number one status screen and then hold down the Left-Arrow key and then tap the ENTER key. You will see a bunch of numbers. On the top line, right in the middle, if the classic has gone to Resting from some awake state, it will show a number which is the RFR.
OK, Resthome. I will gather the numbers for the questions you have asked. Your help is appreciated.
Yes, I use WBJr. and have end amps at 18.5 and absorb time at 1:30. The battery has been reaching float in the afternoons each
day...usually from 1 pm to 2 pm.
The absorb voltage is high but that is what I have found works best after quite a bit of trial and error settings.
The panels are connected in 4 strings of 2 panels each. They are Axitec panels AC-300P/156-72S. Maximum Vmp per panel is 36.73.
Because I have run this system for almost two years...started with different batteries with the forklift installed Oct 2015...and have
had this problem on one occasion but when I inquired at the northern az. forum, I was alerted that it was probably the relay clicking due to low light. At that time, the low light made sense. Now, however, at 2 pm, broad daylight, there seems to be no reason.
I'll try to check for the numbers displayed when the unit has gone to rest as you suggested. The firmware number I'll have to check again. I thought I had it written down. I do not have capability to upgrade the firmware and that too, was verified as an OK firmware to run at Northern Az forum.
Resthome,
Just went to the status screen, held left soft key and hit enter:
IN 4 BAT
Meanwhile, the voltage in was all over the place from 28.4 to 76.8. The sun had not dimmed when the variables were showing.
Thanks again for your help.
You checked all your connections from PV's back to Classic to make sure they are tight and no oxidation or anything ? Also at the breakers?
Larry
Quote from: elesaver on April 14, 2016, 11:03:35 AM
Resthome,
Just went to the status screen, held left soft key and hit enter:
IN 4 BAT
Meanwhile, the voltage in was all over the place from 28.4 to 76.8. The sun had not dimmed when the variables were showing.
Thanks again for your help.
ReasonForResting = 4 Input V is lower than Vbatt while running
As Larry has said check your PV voltage with a good volt meter at the Classic and at the Combiner. You could try setting Classic Mode to off and then open the PV Breaker to Classic. Then check voltage at Combiner for each string with Combiner breakers open, you should see 2 x Voc for each string. If that looks okay try closing one Combiner breaker at a time and close PV breaker at Classic and turn Classic Mode back on. If default setting the Classic should sweep once ever 3 minutes. If in Solar mode the sweeps would be pretty fast and after the sweep the PV In should be some where close to 2 x Vmp. There is a status display on the classic that shows Voc that should be similar to what you measured at the Combiner. Check each string by itself this way.
Something is going on with the voltage In from the PV as you have noted. There have been posts of other with the PV voltage being pulled down near battery voltage, can't recall what the issue was at the moment.
PS. Not part of the resting problem but a suggestion. I would set your Absorb time at 3-4 hrs you may not be reaching end amps with that short of a absorb time. Absorb will go to float at 1.5 hrs even if you have not reach end amps. You also have a high end amps, maybe because of your loads. Check your S/G on you batteries to make sure they are good.
Quote from: ClassicCrazy on April 14, 2016, 11:13:22 AM
You checked all your connections from PV's back to Classic to make sure they are tight and no oxidation or anything ? Also at the breakers?
Larry
As you probably know, Larry but elesaver may not;
It is a generally a good idea to retighten connections occasionally. Copper is well known for "flowing" under the pressure of connections and becoming loose. Loose connections cause resistance and associated voltage drop, possibly skewing the reading of The Classic in this case.
I always use No_OX or similar dielectric grease to prevent corrosion as well. Just an inexpensive step to eliminate future issues.
Tom
Thanks to everyone for the tips. I will work to check connections today although I had already checked the combiner box and found that each string seemed to be flowing OK.
Meanwhile, back at the ranch, where do you find all of the little "nuances" for the classic functions and values? I have the manual but it isn't a great deal of help for the "finer issues." I'd love to be able to learn how to find these additional measurements to troubleshoot or just to know that things are performing as expected. These things can't be expected to last forever so it's good to know if things are beginning to malfunction before you get to the spot that nothing is working!
Thanks again.
not sure how old the manual you have is , but check the Midnite website to makes sure there isn't a newer revision - I think there have been several.
Larry
Quote from: elesaver on April 15, 2016, 11:34:35 AM
Thanks to everyone for the tips. I will work to check connections today although I had already checked the combiner box and found that each string seemed to be flowing OK.
Meanwhile, back at the ranch, where do you find all of the little "nuances" for the classic functions and values? I have the manual but it isn't a great deal of help for the "finer issues." I'd love to be able to learn how to find these additional measurements to troubleshoot or just to know that things are performing as expected. These things can't be expected to last forever so it's good to know if things are beginning to malfunction before you get to the spot that nothing is working!
Thanks again.
There is a REV 2056 Classic Manual, but you won't find the "nuances" there. Most of them come from boB and are posted here on the forum. Sorry I do not know if they have ever been consolidated. When I see one of bob's tricks I cut and past it and save it for reference.
There is one other thing on your panels if you have an amp meter available to check short circuit Isc current of the panel it could be that the voltages look fine unit they are drawing current.
Yes, I had purchased a clamp meter for that very purpose of checking amps out of the panels. Sadly, I am deficient in the use of it! I continue to try to learn. I don't want to disconnect the panels during the sunlight for fear of arching and then, when the sun goes down, I have not disconnected. I guess I need to do that; then, when the sun if up the next day, I can check for output.
If there's an easier way to do this, I'm eager to learn. My learning curve with all of this has been long and slow! Fun, to be sure, but very slow. When I began, I could hardly spell "solar," let alone install a system. Miracles never cease. :-)
If it is a clamp on amp meter all you have to do is open the clamp and place it around the negative cable. Select an appropriate meter scale for AMPs. Some clamp on meters have an arrow or some other indicator as to which direction to clamp the wire. You can try either direction.
If it is just a straight meter the MAX amps for Fluke meters is usually 10A and you have to use the negative jack and the special Amp jack on the meter. The meter would be connected between the positive and negative leads of the string to measure Isc (short circuit current)
I keep a couple pieces of large cardboard to throw over a string of panels if the sun is up. Then I can work on that string of panels.
elesaver;
The whole point of the clamp meter is it does not require opening the circuit to test it. No disconnection. As Resthome mentioned, just open the jaws and put them around the cable. It should read the amps and if it doesn't seem to work or reads negative amps one way, flip the meter over. Unlike wired in meters you can't really hurt it by reversing the wire direction.
Important note:
only clamp around one cable or the net amps will always be zero if you clamp over both plus and minus cables.
Pretty neat units.
Tom
[and if it doesn't seem to work /i] there may also be a RESET or ZERO or CLEAR button to press as some (all?) have some residual memory ;)
OK, then, I can give the amp meter a go. I had looked up online and it showed taking the protective panel off the panel wiring on the back of the units and then use the leads.
Another clue as to the problem...I am seeing "Got COMM?" from time to time. It is a momentary screen. Perhaps the classic is not communicating for some reason?
OK. Out to test amps. :-) I'll report later.
And just to be sure - do you have a clamp meter that will do DC also ? Most models only do AC amps but there are meters that do both AC and DC.
Larry
Yes, this is both an AC and a DC clamp meter. It is a Southwire 21050T True RMS AC/DC Clamp Meter. If I recall correctly, when I
tried putting the negative cable into the space of the clamp, I didn't get the numbers I thought I should have gotten so I figured that
I must be doing it wrong. When the sun is bright tomorrow, I'll try again. It has gotten a little late for good sun now. Thanks for the help.
As others have said - usually for the DC side it may show some current without being on anything and there may be a button to zero it out . Then clamp it on just the positive , and then just the negative . They should be close to the same . You can check each string separate - and then do the main cable after the combiner - all the strings separately should add up pretty close to what you get coming out of the combiner box.
The short circuit current test would be if you had a single panel and took the positive and negative and short them together and put your clamp meter on the wire and see what it says . But you really shouldn't need to do that unless you suspect for some reason one panel in a string is acting goofy and want to find out which one.
You might want to test your meter on a DC circuit where you know the current - just to make sure your meter is working right . Anything you can get to one of the two wires going to the device.
Larry
A good place to test your meter is at the shunt for the WBjr. Clamp it around the negative going to the battery (only cable on that side of the shunt). It should match the reading on the Classic or the Local App for the WBjr.
Quote from: elesaver on April 16, 2016, 05:05:29 PM
OK, then, I can give the amp meter a go. I had looked up online and it showed taking the protective panel off the panel wiring on the back of the units and then use the leads.
Another clue as to the problem...I am seeing "Got COMM?" from time to time. It is a momentary screen. Perhaps the classic is not communicating for some reason?
OK. Out to test amps. :-) I'll report later.
I think it is normal to see that Got Comm from time to time. At least I see it on an occasion. Just shouldn't be there all the time or it indicates a communication problem between MNGP and the Classic
Mystery of clicking solved...the battery offset value was incorrect. After measuring the battery voltage and correcting in the tweaks menu, the clicking stopped and things started working as they had been. Someone had mentioned this may be the problem earlier. We'll see tonight as the sun goes down if the clicking comes back. If it does, I'll know this time it truly is low light. :-)
With the attempt to measure amps, my confusion remains supreme. I have 4 strings of 2 panels each. The panels are 36.73V nominal with 8.71 short circuit amps.
Here's my confusion: my classic never registers incoming voltage above 76V but sometimes it is showing above 50 amps. (This does not account for tenths, etc. but to give the general reading.) When I use the clamp meter on one of the strings, it reads 4 amps. At the combiner box, each breaker reads 75.6V. Inside, at the classic, the amps read 30.6.
When I clamp the wiring between the shunt and the battery, it reads about half the amount showing on the classic. The negative wire coming out of the combiner box registers about half the amps showing on the classic screen also.
Is there any way to help clear my confusion with this?
Quote from: elesaver on April 17, 2016, 02:46:09 PM
Mystery of clicking solved...the battery offset value was incorrect. After measuring the battery voltage and correcting in the tweaks menu, the clicking stopped and things started working as they had been. Someone had mentioned this may be the problem earlier. We'll see tonight as the sun goes down if the clicking comes back. If it does, I'll know this time it truly is low light. :-)
With the attempt to measure amps, my confusion remains supreme. I have 4 strings of 2 panels each. The panels are 36.73V nominal with 8.71 short circuit amps.
Here's my confusion: my classic never registers incoming voltage above 76V but sometimes it is showing above 50 amps. (This does not account for tenths, etc. but to give the general reading.) When I use the clamp meter on one of the strings, it reads 4 amps. At the combiner box, each breaker reads 75.6V. Inside, at the classic, the amps read 30.6.
When I clamp the wiring between the shunt and the battery, it reads about half the amount showing on the classic. The negative wire coming out of the combiner box registers about half the amps showing on the classic screen also.
Is there any way to help clear my confusion with this?
It would be good if you drew out a simple schematic with the voltage and amps at each point you check them.
You won't see as many amps input from the panels because higher voltage and lower amps . If you multiply the volts x amps you will get the Watts .
4 x 76 = 304 watts
304 x 4 strings = 1216 watts
On the output of the Classic to the battery you could see more amps because lower voltage of the batteries output the amps will be greater . If you multiply the amps x volts at the output again you will get Watts . The Watts is comparable between input and output - but not the amps .
So if you batteries are 24v ( I forget what your system is )
1216 watts divided by 24 v = 50 amps
The Classic is not 100% efficient so it will never be exactly the same input and output .
I still don't follow where you checked the output amps - but not all of the output may go to the battery since some of it may be going to loads. The Whizbang system amps is the value actually going to the batteries. The Classic output may be different and a lot more if loads are on. Also even if no loads are on the Classic may be regulating the amps going to the batteries unless the charge state is Bulk when it sends all available power to the batteries. If the Classic is in Absorb or Float it is limiting the amps to the batteries.
Hope that makes some sense - might help if you draw out your system .
Larry
Quote from: elesaver on April 17, 2016, 02:46:09 PM
Mystery of clicking solved...the battery offset value was incorrect. After measuring the battery voltage and correcting in the tweaks menu, the clicking stopped and things started working as they had been. Someone had mentioned this may be the problem earlier. We'll see tonight as the sun goes down if the clicking comes back. If it does, I'll know this time it truly is low light. :-)
With the attempt to measure amps, my confusion remains supreme. I have 4 strings of 2 panels each. The panels are 36.73V nominal with 8.71 short circuit amps.
Here's my confusion: my classic never registers incoming voltage above 76V but sometimes it is showing above 50 amps. (This does not account for tenths, etc. but to give the general reading.) When I use the clamp meter on one of the strings, it reads 4 amps. At the combiner box, each breaker reads 75.6V. Inside, at the classic, the amps read 30.6.
When I clamp the wiring between the shunt and the battery, it reads about half the amount showing on the classic. The negative wire coming out of the combiner box registers about half the amps showing on the classic screen also.
Is there any way to help clear my confusion with this?
Hi elesaver,
It is difficult for me to imagine how the Offset voltage could have been far off enough to cause the Classic to feel that the PV Vin was lower that Vbatt.
AND, it is also difficult to see how that Offset voltage could have been very far off from the factory, or what would have caused it to have changed ...
So, your PVs are 72-cells, and the Vmp is about 36.73, believe that you are saying. In warm weather the Vmp will be reduced, especially in full sun, as, the STC Vmp is for PV cells at 25 C -- room temperature.
Regarding each string of PVs having the same voltage, this will occur, when ALL of the Combiner breakers are closed -- this connects the outputs of ALL PVs together, both on the output busbar, and at the input of each breaker from its respective PV module.
When zeroing your Clamp DC Ammeter, the jaws of the meter need to be fully-closed, and several feet away from any wiring/cables. Many of these meters need to be Zeroed several times. Keep pushing the Zero button until the display on the meter reads 00.00, or 0.00 Amps. And, usually this zeroing will need to be re-done every minute or so. You should monitor that the meter is still zeroed before making any reading (with the jaws closed, and feet away from any wiring).
If your meter never zeroes, or continues to have reading problems when measuring the negative lead from the Shunt to the battery, then, your meter may not be operating correctly. You might try replacing the meter's battery with a fresh one, to see if that helps, if you continue to have reading errors on the Clamp meter.
You have had some good advice already, just my drive-by post. Good Luck, Vic
I'd like to draw the system but I don't see any tools to allow that.
This clamp meter does not have a zero button as such. It is new so the battery should be good although I can test it. There is a "relative" button for zeroing capacitance and offset adjustment, according to the instruction booklet.
For further explanation about the absorb voltage setting: if I don't have that voltage set high enough, the system goes to absorb (even if I have that time to 4 hours) and the batteries never come to full aH state. Then, during the night, the battery voltage drops so that the inverter is showing low voltage by morning. Someone on the Northern Arizona board who uses a forklift battery indicated that he had to do the same thing, I believe. Just thought you'd like to know the reason for the higher setting.
I do check SG from time to time and it is good. I only water the batteries every 4-5 weeks so I'm figuring that's good, too.
Thanks for all the help, everyone!
Hi elesaver,
Since, I believe that you said that your meter reads True RMS, it is probably better than my Clamp DC meter ... on my meter, the zero drifts, and usually takes at least two successive zeroing attempts before it zeroes.
Think that all of these Clamp DC meters use a Hall-Effect DC current sensor, and all of these will have some zero-drift. It is possible that your meter zeroes upon power-up.
This zero-drift could be called an offset ...
So, when you power-up your meter, and DC current mode is selected, does the meter read 0.00 in the display?
On your Absorb voltage, and time, you said,
" ... if I don't have that voltage set high enough, the system goes to absorb (even if I have that time to 4 hours) and the batteries never come to full aH state. Then, during the night, the battery voltage drops so that the inverter is showing low voltage by morning ... "
Just to try to be clear, the Time setting in Classic, is the maximum time that will be spent IN the Absorb stage -- ie the time after the absorb voltage has been reached (and maintained). It is quite possible that you have your WBjr Shunt EA set to a too-high current value for your batteries, and as a result, the Vabs needs to be very high in order to more fully-charge the battery in the Absorb time that is set in the Classic.
Forklift batteries are tall, some are quite tall, which can mean that high Vabs settings might be needed to fully mix the electrolyte ... Also, almost all forklift batteries run fairly high SG electrolyte, and this necessitates relatively high Vabs (but, your almost EQ voltage setting for Absorb does seem high).
Your reference to a "full aH state", could mean that you might, possibly, be relying a bit too much of the WBjr's SOC readout for determining a true full charge. Almost any battery Monitoring device is really only a rough approximation of the actual SOC at any point in time (IMO). As you do know taking careful SG readings is by far the most accurate indication of actual SOC.
FWIW, Vic
Thanks for the tips, Vic. When I first got the forklift batteries installed, I called the manufacturer and asked for EA value. They said they had never been asked that before! Say, what? They told me to set it at 28.7. Anyway, I had remembered from the Northern Arizona forum, the rule of thumb was for 1-2% of aH capacity but since this was the manufacturer suggestion, I went with their number. It worked for a while...which makes sense...but then, the aH and SG were off. I had to do some "jockeying" to get things back to where the batteries were fully charged again during the day. By jockeying, I mean to change the absorb time and the EA...EA set low and Abs time high. After leveling out the battery, I set the EA at 9.3 (1% of aH capacity) and absorb time at 1:30. That, too, was working until the relay clicking began. We know the rest of the story from the postings above. I may need to re-visit the EA value and lower it a bit more. I think I can get it.
So, things are returning to "normal," whatever that means in this variable world of solar! I'm remembering that during the summer with the high temps, I have to watch the batteries to make certain that they don't get overcooked, so to speak. My loads are not extremely high...freezer and refrig only. During the cold, I notice that it is a little harder to get the charging completed without making adjustments.
Thanks again. I'll keep working at it. I think that I will cover two of the panels one of these days and take measurements with the clamp meter. I do believe they are all working properly but it would be smart to confirm rather than assume.
Vic, I didn't address a couple of the other things you mentioned.
Yes, the clamp meter does zero out but it doesn't hold zero for very long. I'm figuring that's normal so I just keep zeroing until I see the 0.00 and then take a reading and push "hold." Because the batteries are receiving some charging and the load is taking some of the current, I don't think I will ever get an accurate reading of the state of the state. That's why I am going to test each of the 4 panel series sets.
And, yes, I am going to lower the EA to 5.0 amps today to see how things go. The battery charge at sundown yesterday was 25.2. At 2.3V per cell required, it should read 27.6. I'm not allowing enough current to flow before it goes to float. The change should correct things...I hope.
Quote from: elesaver on April 18, 2016, 11:39:40 AM
Thanks for the tips, Vic. When I first got the forklift batteries installed, I called the manufacturer and asked for EA value. They said they had never been asked that before! Say, what? They told me to set it at 28.7. Anyway, I had remembered from the Northern Arizona forum, the rule of thumb was for 1-2% of aH capacity but since this was the manufacturer suggestion, I went with their number. It worked for a while...which makes sense...but then, the aH and SG were off. I had to do some "jockeying" to get things back to where the batteries were fully charged again during the day. By jockeying, I mean to change the absorb time and the EA...EA set low and Abs time high. After leveling out the battery, I set the EA at 9.3 (1% of aH capacity) and absorb time at 1:30. That, too, was working until the relay clicking began. We know the rest of the story from the postings above. I may need to re-visit the EA value and lower it a bit more. I think I can get it.
So, things are returning to "normal," whatever that means in this variable world of solar! I'm remembering that during the summer with the high temps, I have to watch the batteries to make certain that they don't get overcooked, so to speak. My loads are not extremely high...freezer and refrig only. During the cold, I notice that it is a little harder to get the charging completed without making adjustments.
Thanks again. I'll keep working at it. I think that I will cover two of the panels one of these days and take measurements with the clamp meter. I do believe they are all working properly but it would be smart to confirm rather than assume.
If you set the Absorb time too short , you are defeating the Ending amps setting because it will time out Absorb cycle before it gets the batteries full and go to float.
Set the Ending Amps and set the Absorb time for a very long value ( 4 hours ? ) while you watch it for a few days. Also keep an eye on the SOC . You want it so that when it gets 100% SOC the ending amps is getting close to cut it off. Check the specific gravity to make sure that at 100% full on SOC they really are.
It makes it a lot easier to watch what is going on by looking at the MyMidnite graphs of system amps , battery voltage, SOC, and charging state . You will see the system amps start to level off and that is where ending amps point is.
Larry
Quote from: elesaver on April 18, 2016, 11:46:08 AM
Vic, I didn't address a couple of the other things you mentioned.
Yes, the clamp meter does zero out but it doesn't hold zero for very long. I'm figuring that's normal so I just keep zeroing until I see the 0.00 and then take a reading and push "hold." Because the batteries are receiving some charging and the load is taking some of the current, I don't think I will ever get an accurate reading of the state of the state. That's why I am going to test each of the 4 panel series sets.
And, yes, I am going to lower the EA to 5.0 amps today to see how things go. The battery charge at sundown yesterday was 25.2. At 2.3V per cell required, it should read 27.6. I'm not allowing enough current to flow before it goes to float. The change should correct things...I hope.
When the sun is out and the batteries are charging check the current with your meter - it doesn't matter if it fluctuates a bit - just watch the real time amps without putting it on hold. What you want to look for is that each string is about the same current - they should all be close if they are the same panels in the same light conditions.
Larry
Quote from: elesaver on April 17, 2016, 02:46:09 PM
When I clamp the wiring between the shunt and the battery, it reads about half the amount showing on the classic. The negative wire coming out of the combiner box registers about half the amps showing on the classic screen also.
Is there any way to help clear my confusion with this?
This shouldn't be. Assume this is the Classic screen you are looking at:
Pressing the STATUS button three times will bring you to the Whizbang Jr.
status screen. There are 4 displayed items here.
This status screen updates live. It displays: Whizbang Jr. temperature,
instantaneous battery current, remaining temperature compensated Amp-hours and
SOC% (if SOC is flashing then the battery has not seen a full charge by going
to float for the first time after turning unit on) Pressing the upper Left
button (Left Soft Key) gets us to the accumulated Amp Hours screen.
This is the Amps that should match you clamp on amp meter at the battery cable. To be sure there is only ONE cable from the battery negative to the Shunt. All other cables should be on the other side of the shunt. Put you clamp on amp meter on the single cable to battery negative.
Also make sure the WBjr setup is set to SHUNT. To enable Whizbang Jr. assisted charging, select “CHARGE†from the main menu. Select “ADVANCED.†Press the soft-left key until the annunciator above it reads “SHUNT†(selecting “CLASC†uses the Classic’s internal shunt instead). Press
Enter to save your choice.
Also make sure the WBjr Temp Comp is set to 25 degrees C. On the second WBjr setup screen you need to set the battery temperature we reference to for temperature compensation for capacity change and voltage adjustment. As a battery changes in temperature, its apparent capacity changes
and the voltage we charge it to needs to change. If the battery temperature is above the “Reference Point†(Hot) we gain capacity and lower the charge voltage. If the battery temperature is below the reference point (Cold) we lose capacity and raise the charge voltage. Most standard batteries use 25 Degrees Celsius as their “Reference Pointâ€. If your battery uses something other than
25C for a reference value, this is where you would set it.
If your meter is still only reading 1/2 of what is on the WBjr status screen try flipping the clamp on in the other direction, shouldn't matter but you never know.
Yes, the WBJr is set to shunt and I access the third screen all the time. The temp. compensation was set at 24.8 so I changed that to 25.0 degrees. So, those things should be good.
Thanks for the connection of the WBJr telling me how many amps are going into the battery! Duh. :-[ When I put the clamp meter on the neg cable, I was in range although it was changing constantly. Close enough for government work. ;D
Everything seemed to work well today. I check the SG and all cells are at 1.285. I'd like to get the battery voltage up to 2.76V from 2.64V. Before I change anything else though, I'm going to let this go for a couple of days and watch the numbers.
Meanwhile, if I had a hat on, I'd take it off to all of you for your willingness to tutor. The pay for your work isn't the best (according to some) but in the times I've had a hand in helping someone with something, just knowing they appreciated it was pay enough. So...I appreciate all of you.
Quote from: elesaver on April 18, 2016, 06:29:32 PM
... Everything seemed to work well today. I check the SG and all cells are at 1.285. I'd like to get the battery voltage up to 2.76V from 2.64V. Before I change anything else though, I'm going to let this go for a couple of days and watch the numbers ...
Hi elesaver,
Thanks for the update, sounding better.
My guess is that 1.285 SG is your probable target. What does the battery manufacturer say is the SG target that you are looking for?
And, when you say that you would like to get the battery voltage to 2.76 from 2.64 (Volts Per Cell [VPC], I assume), what is it that you are trying to accomplish ? ?? ??? If this IS VPC, these EQ voltages, equaling 31.68, and 32.88 volts, respectively. Were you referencing using these voltages for the Absorb, OR, is the decimal point just shifted to the left one place, and you wanted to get to 27.6 V, instead of 26.4 V ?
If you are at or near the manufacturer-specified SGs, then there is no reason to increase Vabs.
Yes, with larger battery banks, it is often a good idea to not change more than one setting at a time, and to not make too large changes at any one time, when the battery is getting fully charged, or nearly so (by SG measurements). And it is usually best to monitor the battery over a few charge cycles before making changes, if battery charging is getting close to the desired parameters.
As you know, SG readings need to be temperature-compensated, when using a Hydrometer, but the compensation value is fairly small, and can be ignored when the battery temperature is about +/-- 10 degrees F, of your reference temperature of 77 or 80 F (usual Ref Temp).
Out of curiosity, what is your battery temperature, as noted in the Temps page on the MNGP? Assume that you have completed your Home Brewed BTS.
Thanks! Vic
Quote from: elesaver on April 18, 2016, 06:29:32 PM
Thanks for the connection of the WBJr telling me how many amps are going into the battery! Duh. :-[ When I put the clamp meter on the neg cable, I was in range although it was changing constantly. Close enough for government work. ;D
Good to see its more in agreement. The amp reading is a little noisy. Mine varies 0.5-1.0 A. So I have to allow for this in my end amps setting. BTW if you use the LA you can dump the WBjr reading for a day and you can plot it in Excel and see the amps as they level (flatten) out. That plus 1A is where you want to set EA. You just need to make sure the time for Absorb is long enough for it to reach this setting. Some where in the forum I posted one of my graphs. I'll try to locate it.
hi John,
Quote
BTW if you use the LA you can dump the WBjr reading for a day and you can plot it in Excel and see the amps as they level (flatten) out. That plus 1A is where you want to set EA. You just need to make sure the time for Absorb is long enough for it to reach this setting.
I don't like Windows but do have a Win 7 machine here for the sole purpose of working with the controllers and logging as the Macs don't seem to be so friendly! when you get a chance could you elaborate on how to plot it in excel? When it comes to any computer im not so bright, I would be gratefully appreciated but no hurry on my behalf! Thank you!!!
Walt
Quote from: BobWhite on April 18, 2016, 09:06:13 PM
hi John,
Quote
BTW if you use the LA you can dump the WBjr reading for a day and you can plot it in Excel and see the amps as they level (flatten) out. That plus 1A is where you want to set EA. You just need to make sure the time for Absorb is long enough for it to reach this setting.
I don't like Windows but do have a Win 7 machine here for the sole purpose of working with the controllers and logging as the Macs don't seem to be so friendly! when you get a chance could you elaborate on how to plot it in excel? When it comes to any computer im not so bright, I would be gratefully appreciated but no hurry on my behalf! Thank you!!!
Walt
If you monitor with the LA for the whole day you can select to export various pieces of data. I just select all of them. It's a CSV file that you can read with Excel. You have to convert the time column to your time zone as instructed in file. You can then insert a line graph selecting the WBjr Amp data vs time. Here is what you get.
http://kb1uas.com/mnsforum/index.php?topic=2364.msg22539#msg22539 (http://kb1uas.com/mnsforum/index.php?topic=2364.msg22539#msg22539)
Thank you John,
One of these days I hope to make sence of the Microsoft office programs ??? ::)
Walt
One final update on this thread. I received a lot of suggestions and information and appreciate all of it. I had mentioned that I wanted to let the system run for a few days to see how it was doing. Those few days turned into a few more than planned but I did want to
update.
I changed some of the settings on the cc. The absorb voltage is 29.5; Float 28.0; Float time 2'15". System now works like a champ! For more than a week, the aH has returned to 938. This is what I was looking for. The manufacturer said that 1.285 is the SG that I need and that is holding, as well. Water consumption has not increased either.
So, all is well...at last. This is how I had expected things to work...and now they do.
Yes, I did complete my "homemade" BTS and its reading corresponds with a mercury thermometer reading so I think things are looking quite promising.
Thanks to all of you who have interjected information that is helpful. Hopefully, if there are others with forklift batteries, this info
may be of help to them, too. So, a Merry Christmas to all and to all, a good night. :-)
Hi elesaver,
Thanks for the update ... we had wondered just how you were doing.
Glad that the battery has come into line with your expectations/needs.
Also great to hear the you completed your HomeBrewed Battery Cap BTS, and it is tracking with your in-electrolyte mercury thermometer. Good Work, all around.
Thanks, Vic