Victron MPPT 75|15
Serial No. HQ14113V1AZ
Victron MPPT 75|15
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)Maximum absorption time Vb <23,8V6h 23,8V<Vb <24,4V4h 24,4V<Vb <25,2V2h Vb >25,2V1h (divide voltagesby2 fora 12Vsystem)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 1Amp, not because of low solar array output but because the battery is fully charged (tail current cut off). This algorithm prevents overcharge of the battery due to daily absorption charging when the system operates without load or with a small load.
3.7.1. Automatic equalization
Automatic equalization is default set to ‘OFF’. By using the configuration toolmpptprefs this setting can be configured with a number between 1 (everyday) and 250 (once every250 days). When automatic equalization is active, the absorption charge will be followed 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 lower maximum current setting has been chosen.
When using the factory default battery type, automatic equalization ends when the voltage limit 16.2V/ 32.4V has been reached, or after t =(absorption time)/8, whichever comes first.
For the user defined battery type automatic equalization ends after t =(absorption time)/2.