Hi,
I have one 410watt solar panel running at 42.3 volt. I meassured it with the multi meter at the mc4 connector directly on the panel.
Now when I connect it to the Victron MPPT 150/35, i only read 33-40Volt in the victron connect app. Avg. 35-36 volt. The panel also doesn’t generate 400watts, but the max i have seen in Greece is 330 watt.
I have around 10 meter of 8 gauge wire through my sailboat, 8.36mm2. Which should be thick enough?
Its a pretty big drop 10-20%…
Any ideas? Thank you
Some comments:
-------
If it's on a boat, it might not be optimally oriented towards the Sun. So expect some power drop from that.
Also if there is any shade, you will have a power drop because of that.
High panel temperature also causes a power reduction.
-------
PV panel open circuit voltage is always higher than PV panel voltage when generating power.
-------
Even if using a 12V battery, the MPPT maximum current to the battery (35A) corresponds with about the maximum power output of your PV panel, so that should not be a limiting factor.
-------
The AWG8/10mm2 wires are thick enough, if those are between the PV panel and the MPPT.
Between the MPPT and the battery you should have thicker wires - 16mm2/AWG6 (and as short as possible).
-------
You have to make sure that the generated power has somewhere to go (charging the battery and/or powering some loads).
