The solar PV input voltage is only achieving about 8V in sunny weather. My PV array runs at 36V, and I measure 30-36V across the disconnected cables right at the input to the MPPT. But as soon as I connect the cables to the MPPT terminals, I only get 8V, both on the Victron Connect app and with my multimeter. Therefore the MPPT won’t charge, because the input voltage is less than the battery voltage.
After investigating all possibilities in the Victron manual, I am starting to suspect a faulty unit. My PV cables are brand new and high quality PV cables, and there is no significant voltage drop between the array and the MPPT.
Please help. URGENT - I am a cruising sailor who relies on this device to provide power to live and work.
Sounds like the unit could be faulty. Did you have a chance to review the Troubleshooting section?
Have you tried resetting the MPPT ?
eg Disconnect the PV from the MPPT. Disconnect the MPPT from the battery. Wait a minute or two. Reconnect MPPT to battery. Reconnect PV. Check voltage at PV terminals.
Another possibility is a bad panel/bad bypass diode but I think that’s unlikely. Depending on difficulty, you could disconnect PV, then remove one or two of the panels from the circuit and see what happens.