Absorb cycle is too short

[Westbranch]

Just back from an extended stay at the cabin..  I have been using the L App to monitor the charge cycles and 4 days ago I noticed that the Watts was doing the expected up/ down as per the graph in the old MX60 manual page 47 ...

THEN I noticed that the BULK phase was ending ~ 11;00  and then , 5 minutes later the L.App showed I had entered FLOAT... I saw this each day after that, 4 times...

Min bulk is set at 2hrs 30 minutes
EA is set to 8 A, Battery is 900Ah AGM

Any hints to figure this out

[Halfcrazy]

Could it have dropped to the 8 amps set in end amps?

[Westbranch]

Hi Ryan, I'll have to sleuth that out on Friday when we are back there.  Still getting used to the WBjr numbers...

The CC was putting out > 12A and the inverter is on constantly drawing +- 2 to 3 amps for standby, modem and wifi router and Bridge with switch...

FYI the 2 arrays are 90 degrees apart,
one gets full sun 10:00 to 14:00 and
then the second is in full sun to Sundown from 14:00 to ~ 18:15. 
So I get 2 blasts of max output, 1 from each set of 4 s panels

[Westbranch]

Hi Ryan, well there I was al set up yo monitor the Local App and see just what I could to explain the short absorb...  Clouds and  rain for 3 days, so never got out of BULK, then day 4 we managed a morning blast before totally clouding over late afternoon but I did not see the short transition to FLOAT as it never got there but I did get 4 hrs of ABSORB...

One thing I did do after 2 days of no sun , because of the clouds etc, was to throw my transfer switch and add another 4S array to the input so I was getting output from 8 panels while the sun was out ~1120W,  SoC was down to ~ 87% and came up to ~ 95%, this might be why it Absorbed rather than Floating..

Reset system to normal config when we left.

Will watch again next week.

[Halfcrazy]

Keep me posted

[Westbranch]

Humpfff...

Well I watched intently for the last 2 days to see if I could get the fast jump to Float occur,  but no luck.  I got upwards of 3 hr of Absorb  day 1 and into Absorb today before I had to leave. 

I did wonder if it had to do with a shallow discharge  (battery at 100% SoC daily), after the midnight reset,  of about 6 % to 94%Soc

I did find that the Absorb Timer was NOT at 4 hours but a few seconds less than that and it decreased as the BULK charging progressed..  same finding today as well...

Is there a reason for this slow reduction ?

[Resthome]

WB

if you had the LA running which it appears you may have you can look at the export data around 11:00am and see what the WBjr amps was at. That will tell you if it near the End Amps setting. You should see exactly when it went to float as the Charge Stage number should change from number 3 Absorb to number 5 Float.  My WBjr amps reading is noisy and jumps around  about 0.5 to almost 1.0 amp and is not a steady reading. I known it is suppose to go below the End Amps for a given period of time but you have to look at your values. The data should still be there for that day but you do have to be connected to the Classic so when you go back select the day in question and check all the data to plot and export it for review.

On your other question, are you saying the Absorb time is counting down while the Classic is in Bulk. If that is true I don't think that should be happening. It should only count down when the battery voltage is a the Absorb set point voltage. Anytime it drops below Absorb due to lack of sun it should stop counting sown until it reaches the Absorb set point voltage again.

Are your two Classics in FollowMe mode?

[Westbranch]

Hi John, in reverse order,

No, the 2 Classics are independent, on separate banks.

Yes, it is counting down, but not in real time, I made some notes that I have to dig up, more later..

Yes, I do have the 'download'ed data, just no time to parse it yet.  Thanks for the tip , I will look for that pattern of being 'close  to the EA' value...

[Westbranch]

Well here we are again on another cloudy  day, with a little direct sun so slow charging.
Started at 92% SoC, now up to 96% and still in BULK \ Mppt...
and the Status/Info page shows (remaining?) ABSORB  time at 3:45:00
Getting 200 +-W ~~26.5V, 5 A from the Classic

ADD:  20:53   now the clock is down to 3:26:32......

and there was no possibility to get to ABSORB  or Float after the first part of this post...??f

[Westbranch]

Ryan, I now have my 2 classics on MyMidnite.  today I note that according to the LA I got 42 minutes in float on #647 at about 12:16 I saw a spike go into Absorb, but it was downhill all afternoon except for a smaller spike...

hth

Eric

[Halfcrazy]

can you email me the log in info for your My Midnite act so i can look at it?

[Westbranch]

Based on Ryan's look at the data in MM I dropped the EA to 4.0 and will try 0.0 if it doe not get more Absorb time.

[Resthome]

Westbranch..

Is your load staying constant? I've seen it jump to float if it was within a couple of amps of the end amp setting and a load like the water pump cycled and drop the absorb voltage and the current enough to meet the end amps. Slight drop and not enough sun to keep the voltage at the full absorb voltage for a minute and the Classic stays in Absorb and then goes to float because it meets end amps.  Not sure how far the voltage has to drop before it falls back to Bulk. I've only seen this in less than max light and in my case it was close to meeting end amps anyway.

In the other case when I am running loads before it goes into float i have to set a higher end amps or it will not meet the end amps before the Absorb timer reaches zero. I've got my Absorb timer set to 4:30 hrs.

In my case End Amps seem to work best with bright sun light and light constant loads.

[Westbranch]

Hi John, the shift through absorb is ~1/2 hr and during full sun starting at ~11:45 as that is when the shadows drop off and getting ~5 -700W..

today we dropped the EA and the LA says it is in float with .1 Kwh 40A and under the absorb voltage

[Resthome]

Hi John, the shift through absorb is ~1/2 hr and during full sun starting at ~11:45 as that is when the shadows drop off and getting ~5 -700W..

today we dropped the EA and the LA says it is in float with .1 Kwh 40A and under the absorb voltage

Something doesn't seem right. So you are only see 1/2hr in absorb before it goes to Float? Do you know what the WBjr amps is at doing this time. It's on the main status page of the LA.(System something). I have no clue, hopefully Ryan can help you out.

That LA Kwh is the accumulative for the day, I'll see 0.3Kwh with all loads off and on a skip day when it just goes to Float( no Absorb), only thing on my batteries is the Classic when I'm gone. 840AH Flooded cells @12V,. So that is about as shallow of a SOC as you can get. Seeing ~ 13.0 hrs of Float time. Of course that is with CA sun and no shadows on panels all day. 

Is that Absorb timer still counting down in Bulk?