The current will continue to reduce during the float stage, when the battery is approximately 80 and 100% charged.
The float stage starts when the batteries are 100% full. During the float stage the charge current is very low.
To find out what the state of charge (SoC) of the battery is, check the battery monitor (if present), or alternatively check the charge
stage the solar charger is in.
• Bulk: 0-80% SoC
• Absorption 80-100% SoC
• Float or storage: 100% SoC
6.4.2. 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 system battery monitor is correctly installed and configured 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.
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.
6.4.3. Insufficient solar
Check if the solar charger reaches the float charge stage each day.
To investigate look at the history tab in the VictronConnect app. The histogram displays how long the batteries have been
charged in the Bulk, Absorption and Float stage each day, for the last 30 days. If you click on one of the histogram columns you
will see a breakdown of the charge stages.
You can use the charge times to see if the PV array is properly sized for your requirements. A system which never reaches the
float stage could have the following issues:
• Not enough solar panels
• Too much load
• A problem with the array causing it to have a reduced power output.
• For more potential reasons see paragraph: “PV power or yield less than expected”
System spending all its time in bulk with breakdown of charge stages - System in bulk and absorption
6.4.4. Battery charge current too low
Check the “Max charge current” setting in the VictronConnect app or via the display.
If the “Max charge current” has been set too low, it will take longer to charge the batteries and/or the batteries will not be fully
charged at the end of day.
6.4.5. 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.
6.4.6. Battery cable voltage drop
If there is a voltage drop over the battery cables, the solar charger will output the correct voltage, but the batteries will receive a
lower voltage. Battery charging will take longer, and this can potentially lead to undercharged batteries.
Multi RS Solar
Page 27
Troubleshooting Guide - MPPT
