Good afternoon everyone, I’m looking for some electrical / wiring advice.
I have finally taken the plunge and bought 2 x 100w semi flexible solar panels and MPPT.
I have a split relay from alternator to leisure battery with a Victron shunt monitoring battery charge and % charge (110a Lead Acid battery). Also have 240v EHU wired in and all works well.
Just bought a Victron 30 amp MPPT and 2 x 100w solar panels. Plan to wire the 2 panels in series to maximise charging in partial shade. Also have all the required wiring harnesses.
What is the method for wiring these?
Does the SR connect to MPPT and then MPPT to battery or does the SR and MPPT both connect to leisure battery separately.
I want the leisure battery to be charged both off alternator and solar depending on whether the engine is running. Will the battery also charge off solar whilst being charged from alternator.
What is a split relay? Do you mean a battery combiner like a Cyrix or a diode module like an Argodiode/Argofet? Do you have a schematic?
If you want the MPPT to charge the leisure battery, then you need to connect it to that batteries positive and negative poles. This should not change anything in the existing charge circuit
If you look up that VSR (I had one in my narrowboat) it is dual sensing.
Dual sensing operation - charges from starter battery to leisure battery when alternator is running and charges from leisure battery to starter battery when mains charger is connected.
Therefore, it does not matter which battery you connect the solar to, the other one will charge. As you are adding solar to an existing install, connect the MPPT battery positive to the battery with a fuse at the battery and the MPPT battery negative to the system side of the Shunt.
Yes, it is OK to have solar and alternator charging together, as the batteries get full, one of the chargers will shut down first, usually solar as that goes to float and the alternator stays at higher voltage.
