You can start out with what you have for ending amps. The way I do it is to watch the SOC on Mymidnite along with the system amps . As the SOC counts up towards 100% then the system amps should start to level off. I also take a few specific gravity readings from the batteries to confirm that when it gets to 100 % SOC that the SG reading is what is recommended by the battery manufacturer. You also need to set the battery efficiency in the Midnite SOC settings. Once you get all that stuff tweaked it should be ready to go and work pretty good.
Vic would tell you to label all your cells on your batteries and to take initial SG readings in a notebook, and then you have a reference to go by for the life of the batteries and can use that to also find cells in the future that may be getting low compared to the others . You can adjust your equalization according to that too over time.
Good to know.
I pulled up the Rolls "Battery User Manual" pdf and started reading. Came across this on page 13:
"END AMPS OR RETURN AMPS
As batteries near full capacity the charge current drops. End Amps or Return
Amps generally refers to the lowest amount of current (Amps) running from the
charger when the batteries have reached full capacity and are no longer accepting
a charge. Some charges will measure the actual current output. If the charge
current drops to the End Amps or Return Amps set point, this will trigger the
charger to shut off. This setting is typically 2%-3% of the 20 Hr AH rating (C20)
of the battery bank. Rolls recommends setting this at 2% for new installations."
According to this, they are apparently wanting the battery settings as such:
(1) S550 = 428 AH
(2) Three serial strings of the S550 yields a pack with 1284 AH
(3) 1284 AH x .02 = 25.68 Amp cutoff
I can't get my head around a cutoff this high. Maybe I'm making a calculation error?