Hi just wondering if anyone can help me as im a newbie have a 120w solar panel on caravan wich generates 21.4 volt at the wires going in to in to mppt when disconected measjred with fluke multi meter, battery shows 12.5v however charger says its off and also shows in blue tooth app solar lower than the battery volts,
Could this mppt be faulty?
Thanks
You will have to wait until your panel is 5v above battery voltage before the MPPT will start the charge cycle for the day. in your case that means waiting until solar voltage is 17.34v when connected to the MPPT, not open circuit. If your panel is flat on the roof of the van, that might mean waiting for the sun to rise a bit in the sky. You can add a second panel in series to double the voltage, this will make the charge cycle start earlier.
If you have now got batt +5v from the array, it could be that charging is switched off in the battery settings.
Had very similar issue with mine. Turned out it was the connectors joining cables from the solar panel to the cables to the MPPT unit that were faulty.
