6.3.6. Battery full
Once the battery is full the solar charger will stop charging or will greatly reduce the charge current.
This is especially the case when at the same time the DC loads in the system are not consuming any power from the battery.
To find out what the state of charge (SoC) of the battery is, check the battery monitor (if present), or alternatively check what
charge stage the controller is in. Also observe that the solar cycle is (briefly) progressing trough these charge stages at the
beginning of the daily charge cycle:
• Bulk stage: 0-80% SoC
• Absorption stage 80-100% SoC
• Float or storage stage: 100% SoC.
Be aware that it can also be possible that the solar charger thinks the battery is full, while in reality the battery is not full. This can
occur when the charge voltages have been set too low, causing the solar charger to prematurely switch to the absorption or float
stage.
6.3.7. The charger is disabled
Check the VictronConnect app to make sure the charger has been enabled.
VictronConnect charger enable/disable setting
6.3.8. Controlled by an external device
The solar charger can be controlled by an external device. The external device can stop or reduce the charge current to the
battery.
There are different types of external control:
• Managed batteries or an inverter/charger with an external control system system can control the solar charger via a GX device.
The battery dictates if charging is allowed, and when charging is allowed, what charge voltage and currents are used. If
external control is active this will be displayed in the VictronConnect App and also on the GX device.
• The BMS of a managed battery can directly turn the charger on or off via a remote L/H connections.
If the charge settings are correctly set and if all battery cells are balanced, the BMS should never disallow charging. The BMS
will disallow charging when the cell voltage of one (or more) battery cells is too high or when the low temperature cut off is
enabled and the battery temperature has dropped below the temperature threshold.
• An external device or a switch can turn the solar charger off via the remote on/off terminal. For more info see
???
.
6.4. 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.
6.4.1. 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.
The first current reduction takes place at the end of the absorption stage, when the battery is approximately 80% charged.
Multi RS Solar
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Troubleshooting Guide - MPPT
