Batteries Are Undercharged; Too Much Dc Load; Battery Charge Voltages Are Too Low; The Battery Is Almost Full - Victron energy SmartSolar MPPT 75/10 Manual

MPPT solar charger manual
VictronConnect: screenshot of an Error #33 and a screenshot of the history indicating an error
Check the open circuit voltage (Voc) rating of the PV array. Ensure that it is less than the maximum rated voltage of the solar
charger. Use the MPPT sizing calculator on the solar charger product page. In case the PV array is located in cold climates or if
the night temperature drops close to or below 10°C the PV array can output more than its rated Voc. As a rule of thumb, keep a
10% safety margin.
An overvoltage event can damage the solar charger, depending on how much the maximum PV voltage was exceeded. This
damage is not covered by warranty.

9.3. Batteries are undercharged

This chapter deals with possible reasons why the solar charger is not sufficiently charging the batteries and the steps you can
take to check or remedy the situation.
Some signs of undercharged batteries:
• The batteries take too long to charge.
• The batteries are not fully charged at the end of the day.
• The charge current from the solar charger is less than expected.

9.3.1. Too much DC load

The solar charger does not only charge the batteries, it also provides power for the system's loads.
The battery will only be charged when the power available from the PV panels exceeds the power being drawn by the loads in the
system, like lights, fridge, inverter, and so on.
If the solar charger has a dedicated load output (10, 15 or 20A model), then it can easily be checked how much power the PV
array has generated and how much power is used by the loads. This is providing that all loads are connected to the load output
and are not connected directly to the battery.
If the solar does not have a load output, it might have a battery monitor installed.Then you can see how much current is going in
(or out) of the battery and the solar charger will tell you how much current the solar array is generating.
In both above cases, a positive sign alongside the current reading means that current is flowing in to the battery, while a negative
sign means that current is being drawn from the battery.

9.3.2. Battery charge voltages are too low

If the battery voltages have been set too low the batteries will not receive a full charge.
Check if the battery charge voltages (absorption and float) are set correctly. Consult the battery manufacturers information for the
correct charge voltages.

9.3.3. The battery is almost full

The solar charger will reduce its charge current when the battery is almost full.
If the state of charge of the battery is unknown, and the current is reducing while the sun is still shining, it can mistakenly be
interpreted as the solar charger being faulty.
Th first current reduction takes place at the end of the absorption stage, when the battery is approximately 80% charged.
Page 43 Troubleshooting and Support