Victron energy BLUE POWER BlueSolar MPPT 150/35 Manuel page 10

3.7 Battery charging information
The charge controller starts a new charge cycle every morning,
when the sun starts shining.
The maximum duration of the absorption period is determined by
the battery voltage measured just before the solar charger starts
up in the morning:
Battery voltage Vb (@start-up)
Vb < 23,8V
23,8V < Vb < 24,4V
24,4V < Vb < 25,2V
Vb > 25,2V
(divide voltages by 2 for a 12V system and multiply by two in case
of a 48V system)
If the absorption period is interrupted due to a cloud or due to a
power hungry load, the absorption process will resume when
absorption voltage is reached again later on the day, until the
absorption period has been completed.
The absorption period also ends when the output current of the
solar charger drops to less than 2Amps, not because of low solar
array output but because the battery is fully charged (tail current
cut off).
This algorithm prevents over charge of the battery due to daily
absorption charging when the system operates without load or
with a small load.
8
Maximum absorption time
6h
4h
2h
1h