OK... please let us clarify a few things before running & calling fowl.
29.2 Volts = 3.650 per cell in an 8S configuration (24V std spec).
There is ABSOLUTELY no Point in continually charging LFP to that voltage.
What you are experiencing here is more than likely a Runner cell hitting cutoff ahead of the others. That triggers a BMS to cut the line and the charger will see that disconnect and stop. A "Runner" is a cell with a lower IR that will reach full before the others. These may "also" run down to 2.50 before the other cells. This isn't unexpected from bulk & lower graded cells. The KEY is to charge to the point where the cells do not deviate too much between themselves (BMS SETTINGS APPLY) and so that the BMS does not get to a forced cutoff point. In "REALITY" that means being gentler with the battery packs, meaning don't charge them above actual Working Voltage Range, Don't push too many amps too fast (higher amps increases cell deviation) and if using multiple packs in parallel, ensure they are all similarly configured.
Grade A+ LFP "Working Voltage" is from 2.800-3.500. Grade-A 2.900-3.450, Grade B 3.000-3.400, Bulk +/- 10% from B.
-- 3.5 to 3.65 is the Cliff Climb and represents less than 3% of gross cell capacity.
-- from 2.800 down to 2.500 is the Cliff Fall in the voltage curve, this again represents less than 3% of gross cell capacity.
All LFP cells when fully charged to 3.650, and saturated to where they take less than 2A charge rate (meaning completely full) will still settle to 3,500 +/- within 60 Minutes after charge has stopped, This is Perfectly Normal for this chemistry.
Try to match these settings, you will not get the cutoff issues, the cells will float & level up & balance without a hard push and you'll get a longer lifespan from your packs. I use Midnite Solar & Other equipment but the settings are similar (some terms a little different)
All equipment MUST BE Voltage Corrected & Calibrated (VERY IMPORTANT) see link in my signature on how to do it.
Divide Values X2 for 12V. Multiply X2 for 48V.
Absorb: 28.2 for 15 minutes (3.525vpc)
(some call this boost)
Equalize: OFF
Float 27.9V (3.4875vpc)
MIn Volts: 22.0 (2.750vpc)
Max Volts: 28.7 (3.5875vpc)
Rebulk Voltage: 27.7 (3.4625vpc)
End Amps: 14A (*1)
(*1): End Amps is calculated from the Highest AH Battery Pack in a Bank. IE: 200AH X 0.05 = 10A 280AH X 0.05 = 14A.
NB: Victron Forum discussion says EndAmps = TailCurrent
This get's the bank charged to full with high amps (Constant Current) and then float (Constant Voltage) tops off so the cells are on average between 3.475-3.500. I am running 7/24/365 so float is used up by the Inverter + provides whatever the packs will take to top off.
** Coulumbic Efficiency for LFP is 99%
Hope it helps, Good Luck.
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