I’m aware that an MPPT controller should first be connected to the battery before connecting to the solar panels, but is this on first use only to let the system know the battery voltage, or will an MPPT be damaged by later disconnection from the battery whilst power is being received from solar panels?
The reason I ask is that there are circuit breakers/fuses between the MPPT and the batteries and it seems pointless to have protection that will kill the MPPT if it actually works.
Circuit breakers/fuses are for protection against cabling faults, heavy overload. If they do disconnect and damage the MPPT, it's likely that this saved you from a much worse situation.
You should have isolators between the panels and MPPT. In normal use, use them to disconnect the panels.
That doesn’t really answer my question.
Does it damage the MPPT to be connected to the solar panel but not the battery?
Incidentaly, I’m not going to fit an isolator between a 22W solar panel and a 75/10 MPPT. There’s just no point. The voltages and current are very small.
