New out of the box. I connected 5 panels in series to the controller. Zero volts show up. Then I connected 1 panel to the controller. Measuring voltage across the MC4 connector is 21.0V as soon as I plug it in? Zero volts. Help?
asked
Victron SmartSolar MPPT 150/85-MC4 Not showing panel voltages.
@TheSniper, 99% of the time this happens it's because you have PV polarity reversed at the MPPT input; with the MC4 version the odds of this are minimized but I've seen quite a few factory MC4 connectors that are technically reverse of what I would expect because they're anticipating that extension cables are going to be used. Double check your connection polarity and report back! You might well be in the other 1%, but it's worth checking as a starting point.
Ditto
Polarity
Also due to 4S (series) you might have either got something killing the voltage in the series so check each panel as well if it keeps up.
You have the battery connected first too before all this right (not the problem but important to your controller)?
