SOC 50% or 84%

[Jacotenente]

From what I read...if a 24v battery bank is at 24v, it should be 50%. In the morning before charging occurs, the Classic 150 reads ~84% SOC (battery volts at 24v). Whizbang Jr and temp sensor installed. Parameters correctly set for my battery bank. And while charging (say around 11 or 12 noon) it actually drops to 79% in Absorb.

50 or 84% SOC?

Thanks.

[Westbranch]

A couple more questions ... 
What do you have end amps set at?
How long is Absorb?
How old is the bank?
Have you done an EQ since adding the WBjr?
Have you taken any SG reading after an EQ?

[Jacotenente]

Hey Westbranch - Thanks. Here are my readings for the questions you have. I also took a picture of the "End Amps" screen.

End Amps: 0.0
Absorb time: 3 hours
Battery Bank Age: 1 Year
EQ after Whizbang Jr install: Yes
SG (Specific Gravity) reading after EQ: No

I did inspect the batteries after I converted them to 24v and they looked excellent. Acid levels same as new.

[Resthome]

What is your Battery Temperature and how do you have the Temp Compensation set up? Also what is the Battery Efficiency in the SOC Setup set to? I believe it defaults to 94%. to match my Link10 battery monitor which is set to 90% I have to change mine to 90% and then they agree with each other. Only the Net Ahr is slightly off between the two. In other words I need to put in 10% more than I take out of the batteries to get back to 100% SOC.

Have you verified the and calibrated the Battery voltage at the Classic terminals?

That drop later in the afternoon in Absorb maybe because of your loads. What is the WBjr showing for NET Amps at that time?

[Westbranch]

Wow, that EA is too low, it should be around 1% of your battery bank Amp rating ~ 3A to 4A, depending.... At  0.0A,  you will never reach it...  Also the only way to verify the real SoC is with a Hydrometer.

You might also need to extend the time to absorb until you have those batteries truly full.. 
When you did the EQ, how long did it run and what temp did the batteries get to. 

Also are you using any water.?  with the present setup?

Acid levels same as new.

You should be using some, if not the Absorb may/is not long enough and/or  the voltage may/is not high enough.  SG numbers are what you need for all cells.

[Resthome]

I think when End Amps is set to 0 the function is turned off and just uses the Absorb Timer. So I don't think he is  using End Amps. although I think there is another check box in the Local Amp which says Use WBjr for End Amps or something like that.

[Westbranch]

I think you are correct on that one (EA) John.. I seem to remember that box on the LA.... 

I/we head west to do the first post winter inspection tomorrow AM, boost charge or whatever else is needed.  I think I might need a 3 rd Classic just to look at... but SWMBO would go snakey 

[Jacotenente]

Thanks. The absorb volts are set to 29.0v. I bumped up the absorb time to 4 hours. Float is set to 27.5. I took a screenshot of the temp compensation screen (see below)

[boB]

The Whizbang Junior and the associated firmware to calculate SOC % only uses amp-hours in and out right now.

When you charged the battery some and the SOC went down, is it possible that the shunt is wired backwards ?
That purple wire coming out of the WB Jr. circuit board should be pointing to the battery negative terminal.

The Ending Amps is fine at 0.0 amps.  It's just disabled at that setting.  When the charge stage goes from
Absorb to Float, it will set the SOC  to 100 percent at that time.

Good questions on the temperature etc.  Also, go to the MNGP setup-more screen and make sure that
the temperature reference is not sitting at 10.0 C. It is usually set for 25.0 degrees C.

Some got out with a setting of 10.0 degrees C.  But I don't ~think~ that is related to this problem.
Might be wrong there though.

boB

[Jacotenente]

Hey boB - Yep the WB Jr is wired correctly (purple lead pointing toward the battery neg). Also, the SOC does go to 100% when switching from absorb to float. The temp compensation (see picture above) is set at 25 deg C. As of the moment the SOC is going down (daylight gone, discharging).

Attached is a screen shot of what I have my battery parameters set at. Each single 12v deep cycle battery is stamped at 114 amp/hours. I have six. Because they are wired in series (24v system), I divided and inputted 342 amp/hours.

Chris

[Westbranch]

..  in series voltage adds up and amps stay the same...
....  in parallel amps add up and Voltage stays the same..

So you correctly have 3 strings of 114 Ah  for a total of 342AH

How about the SG readings?

[Resthome]

That's Temp Compensation for Charging.  There is another one for the WBjr Setup.  Not sure where it is on the Local App. BTW what version of the LA are you using and what version is the firmware for the Classic and MNGP? Go to the MNGP and press the status button three time to get to the WBjr screen then press SETUP then MORE you should see Battery Capacity Temp Comp there you should see a setting for the temp reference where no compensation occurs. Make sure it is 25.0 C or what ever the setting is for your batteries.

Also what is the Batteries actual Temp? And when you say the SOC is decreasing while in Absorb what is the NET amp showing at that time?

[Jacotenente]

Thanks. Here is what I have:

Firmware Rev: 1923
Network Rev: 1839 Classic was purchased 2 months ago
Battery Temp Settings: 25 deg C at 1% compensation
Amp/Hour efficiency: 94%
Actual temp: 23 deg C
Net Amp: -65

I am in Bulk Mode right now...showing 80% charged at 25.4v on the battery. Before daylight charging it was at 84%.

[stuman]

Strictly from a "resting voltage" standpoint, if a 24 volt battery bank reads 24.0 volts, it is completely discharged.  50% should read 24.4. at rest.

[vtmaps]

Strictly from a "resting voltage" standpoint, if a 24 volt battery bank reads 24.0 volts, it is completely discharged.  50% should read 24.4. at rest.

That is not correct for most flooded lead acid batteries. 

If you never wish to discharge below 50%, then you might want to call 50% SOC fully discharged, but that is a bit confusing.

--vtMaps