Batterylife; Virtual Load Output; Battery Charging; Adaptive 3-Stage Battery Charging - Victron energy BlueSolar MPPT 75/10 Manual

Solar charger system with DC loads connected directly to the battery via a BatteryProtect controlled by the load output

3.8.1. BatteryLife

When the solar charger is not able to recharge the battery to its full capacity within one day, the result is often that the battery will
continually be cycled between a 'partially charged' state and the 'end of discharge' state. This mode of operation (no regular full
recharge) will destroy a lead-acid battery within weeks or months.
The BatteryLife algorithm will monitor the state of charge of the battery and, if needed, day by day slightly increase the load
disconnect level (i.e. disconnect the load earlier) until the harvested solar energy is sufficient to recharge the battery to nearly the
full 100%. From that point onward, the load disconnect level will be modulated so that a nearly 100% recharge is achieved about
once every week.

3.8.2. Virtual load output

A virtual load output can be created to control a load who's current rating is larger than the current rating of the solar charger's
load output.
To create a virtual load output:
• Use the VE.Direct TX cable and enable it to act as a virtual load output via the VictronConnect App RX port function.
The virtual load output can be setup via the VictronConnect App and can be driven using battery voltages or the BatteryLife
algorithm.

3.9. Battery charging

3.9.1. Adaptive 3-stage battery charging

The solar charger is a 3-stage charger. The charge stages are: Bulk – Absorption – Float.
Bulk
During the bulk stage the solar charger delivers the maximum charge current, to rapidly charge the batteries. During this stage
the battery voltage will slowly increase. Once the battery voltage has reached the set absorption voltage, the bulk stage stops and
the absorption stage will commence.
Absorption
During the absorption stage the solar charger has switched to constant voltage mode. The current flowing to the battery will
gradually decrease. Once the current has dropped below 1A (tail current), the absorption stage stops and the float stage will
commence.
When only shallow discharges occur the absorption time is kept short. This to prevent overcharging of the battery. But if the
battery was deeply discharged, the absorption time is automatically increased, to make sure that the battery is fully recharged.
Float
During the float stage the voltage is reduced and batteries full charged state is maintained.
A storage stage is not needed for a solar charger, unlike is the case for an AC charger, since at night there is
no solar power, so battery charging will stop.

3.9.2. Flexible charge algorithm

The VictronConnect App allows selection of 8 pre-set charge algorithms, or alternatively the charge algorithm is fully
programmable. The charge voltages, stage duration and the charge current can be customized.
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MPPT solar charger manual
DC loads
Features