Absorb cycle is too short

[Westbranch]

the puzzle continues...  today it did NOT go into ABS, but stayed in BULK all day. 

Day1, changed CC 647 out at ~12:00, starts in Abs ~ 13:53 to sundown, Batt resting @ 23.8V,
Day2 Batt @ 23.7V heads to ABS ~ 09:00, Float ~ 12:50, Batt resting at 23.6V,
Day 3 Batt at 23.4V max BULK at 23.9V,  .6KWh   Batt resting at ~23.6V...

At least today we added ~ the overnight amount of power, headed out tomorrow to start up the genny and BULK it for a few hours... Naturally the long range outlook is for SUN... for 5 days...

If you look close you can see the ~ 2 hr apart overnight drops in V ~ .1V

[Resthome]

Eric

Can not view the graph for CC 647 in your Word doc

[dgd]

the puzzle continues...  today it did NOT go into ABS, but stayed in BULK all day. 

Day1, changed CC 647 out at ~12:00, starts in Abs ~ 13:53 to sundown, Batt resting @ 23.8V,
Day2 Batt @ 23.7V heads to ABS ~ 09:00, Float ~ 12:50, Batt resting at 23.6V,
Day 3 Batt at 23.4V max BULK at 23.9V,  .6KWh   Batt resting at ~23.6V...

At least today we added ~ the overnight amount of power, headed out tomorrow to start up the genny and BULK it for a few hours... Naturally the long range outlook is for SUN... for 5 days...

If you look close you can see the ~ 2 hr apart overnight drops in V ~ .1V

I wouldn't be worried about Absorb being too short as IMO this battery bank is heading quickly to its life end.
Resting voltages after charging of 23.6 is nothing short of a disaster.
Get a genny fired up and a good long charge into the bank, 20+ or longer hours, until the resting voltage is up over 25 volts. You may need to repeat this bulk genny charge several times.

Just MHO..

dgd

[dgd]

I also just noticed your sig line..

CL150 #647 175A E-Panel  WBjr , 2 x 4s 140W to 24V 900Ah AGM, 

Assume thats two by strings of four 140W pvs?
Thats only 1120watts nameplate max of PV, way way too little to charge that 900Ah bank in your winter's less than optimal insolence conditions.
I would be getting that pushed up to more than twice the capacity of PVs, four strings of four (minimum) or more
likely five strings of four but preferably four strings of five PVs. The Classic 150 would easily cope with mpv of 90 volts and a 2.8Kw array of 140 watt pvs.
Thats exactly what I use, 4 strings of 5 140W pvs in series. Pic shows 2100w of 3 by 5 but since upped to 4 by 5 for 2800watts
No (over)heat issues either

dgd

[ClassicCrazy]

Kind of hard to know from the graph what is going on without knowing what the load on the system is .
The last graph actually looks normal in some ways - it won't go out of bulk to absorb unless the battery voltage goes up - which on the graph it does not look like it does.

Larry

[Halfcrazy]

the puzzle continues...  today it did NOT go into ABS, but stayed in BULK all day. 

Day1, changed CC 647 out at ~12:00, starts in Abs ~ 13:53 to sundown, Batt resting @ 23.8V,
Day2 Batt @ 23.7V heads to ABS ~ 09:00, Float ~ 12:50, Batt resting at 23.6V,
Day 3 Batt at 23.4V max BULK at 23.9V,  .6KWh   Batt resting at ~23.6V...

At least today we added ~ the overnight amount of power, headed out tomorrow to start up the genny and BULK it for a few hours... Naturally the long range outlook is for SUN... for 5 days...

If you look close you can see the ~ 2 hr apart overnight drops in V ~ .1V

Ok so the classic function looks normal. If there is no power from the sun to speak of the classic can not fill the battery. Or are you saying on Day 3 there was tons of sun and the classic did not use it?

[Westbranch]

the puzzle continues...  today it did NOT go into ABS, but stayed in BULK all day. 

Day1, changed CC 647 out at ~12:00, starts in Abs ~ 13:53 to sundown, Batt resting @ 23.8V,
Day2 Batt @ 23.7V heads to ABS ~ 09:00, Float ~ 12:50, Batt resting at 23.6V,
Day 3 Batt at 23.4V max BULK at 23.9V,  .6KWh   Batt resting at ~23.6V...

At least today we added ~ the overnight amount of power, headed out tomorrow to start up the genny and BULK it for a few hours... Naturally the long range outlook is for SUN... for 5 days...

If you look close you can see the ~ 2 hr apart overnight drops in V ~ .1V

Ok so the classic function looks normal. If there is no power from the sun to speak of the classic can not fill the battery. Or are you saying on Day 3 there was tons of sun and the classic did not use it?

Ryan the opposite is true, when I swapped out 647 there was a short period on the LApp of 600+ watts and under full sun I watched the Classic self regulate down to ABSORB  V  and minimal amps.  I concur the Classic now seems to be operating normally, that is part of the puzzle...??

DGD et al Presently I have added all panels to this one battery so there are 1680W available under STC ...

[Westbranch]

Eric

Can not view the graph for CC 647 in your Word doc

John added a n earlier version of the doc  see original post above

ADD:

DGD, There is a constant 3 to 5 amp load from the inverter for standby and to run the WiFi and Modem for the connection to MyMidnite monitoring ..PLUS the cyclical loads to run the fridge, so the steady at rest line shown is not truly "at rest" with no loads etc... just the closest I can get...

[Resthome]

Eric

Can not view the graph for CC 647 in your Word doc

John added a n earlier version of the doc  see original post above

Did not realize you appear to have swapped out the #647 controller.

[Westbranch]

~ noon, Sept 23, on line ~14:00   

[Resthome]

~ noon, Sept 23, on line ~14:00   

So is the conclusion that 646 is not acting normal?

I agree it looks like the lightly loaded AGMs are reading low for a 24v system unless the frig is running. Will be interesting to see what voltage they are at afer you hit them with the generator.

[Westbranch]

Here is today's production.... 5.2kWH....  best ever, no gen set yet,  highs of 50.1A, 27.4V .... daytime temp 10*C & cool breeze...

ADD:::   high of 1371W captured by LApp

up from 23.4 this AM
sundown 25.0V will see what steady state gets to...


the Puzzle is why did the CC go into ABSORB, on day 1 (and 2), when it should have stayed in BULK for a lot longer???

[dgd]

Here is today's production.... 5.2kWH....  best ever, no gen set yet,  highs of 50.1A, 27.4V .... daytime temp 10*C & cool breeze...

up from 23.4 this AM
sundown 25.0V will see what steady state gets to...


the Puzzle is why did the CC go into ABSORB, on day 1 (and 2), when it should have stayed in BULK for a lot longer???

because the Absorb voltage set point is too low.
What are the Absorb and Float voltages?
That high of 27.4 looks a bit miserable too, was that during Bulkmppt?
Good news is the Classic is working perfectly.

Getting that third string of PVs connected certainly seem to have helped but I still think you need to get that 4th and 5th strings installed before your winter weather turns to custard.

That bank now disconnected gives you the opportunity to get the genny working on it and get its resting voltage way up over 25 volts.

dgd

[Westbranch]

because the Absorb voltage set point is too low.
What are the Absorb and Float voltages?
That high of 27.4 looks a bit miserable too, was that during Bulkmppt?
Good news is the Classic is working perfectly.

Getting that third string of PVs connected certainly seem to have helped but I still think you need to get that 4th and 5th strings installed before your winter weather turns to custard.

That bank now disconnected gives you the opportunity to get the genny working on it and get its resting voltage way up over 25 volts.

dgd

DGD, in reverse order:

Well it's actually the other (backup) bank that is resting.  The active one is the weaker of the 2, it was .2V/cell than the resting one at time of purchase...  I want to use it till it drops, experiment, etc...

I concur about the next sets of arrays but there is more equipment work to happen where they have to go, first, then the array footings..

I am hoping there is just some small tweak needed to have both CC's running smoothly.  The latest FW , on days like today, is smashing...

The Absorb is set at the max, 29.2V,  highest V allowed is 29.5V      EA is WBjr controlled and at 0.0
Float is 27.2 max 27.6
That 27.4 might have gone a bit higher but there were a few scattered clouds,  I did not expect much higher for the first honest charge in over a week, 9 days actually... we will see tomorrow! more sun forecast

[Westbranch]

another good day...  4.0 kWh, 3 1/2 hrs charge @ 30A then solar,  max 45.1A .
Holding steady state at 24.8, stated day at  23.8V,
shall see in the morning.
Another BULK by genny day