Battery Charging Information - Victron energy MPPT 75/10 Manuel

3.7 Battery charging information

The charge controller starts a new charge cycle every moring, w hen 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)
23,8V < Vb < 24,4V
24,4V < Vb < 25,2V
If the absorption period is interrupted due to a cloud or due to a pow er hungry load, the
absorption process will resume w hen absorption voltage is reached again later on the day,
until the absorption period has been completed.
The absorption period also ends w hen the output current of the solar charger drops to less
than 1 Amp, 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 w hen
the system operates w ithout load or w ith a small load.
3.7.1. Automatic equalization
Automatic equalization is default set to "OFF". By using the configuration tool mpptprefs
this setting can be configured with a number betw een 1 (every day) and 250 (once every
250 days). When automatic equalization is active, the absorption charge w ill be follow ed by
a voltage limited constant current period. The current is limited to 8% of the bulk current for
the factory default battery type, and to 25% of the bulk current for a user defined battery
type. The bulk current is the rated charger current unless a low er maximum current setting
has been chosen.
When using the factory default battery type, automatic equalization ends w hen the voltage
limit 16.2V / 32.4V has been reached, or after t = (absorption time)/8, w hichever comes first.
For the user defined battery type automatic equalization ends after t = (absorption time)/2.
When automatic equalisation is not completely finished w ithin one day, it w ill not resume the
next day, the next equalisation session w ill take place as determined by the day interval.
3.8 VE.Direct com munication port
Several parameters can be customized (VE.Direct to USB cable, ASS030530000, and a
computer needed). See the data communication w hite paper on our w ebsite.
The required software can be downloaded from
http://www.victronenergy.nl/support-and-downloads/software/
The charge controller can be connected the to a Color Control panel, BPP000300100R, w i t h
a VE.Direct to VE.Direct cable.
6
Vb < 23,8V
Vb > 25,2V
(divide voltages by 2 for a 12 V system)
Maximum absorption time
6 h
4 h
2 h
1 h