Just installed a new 100/30 charge controller. The blue light slow flashes. I have 4:100w mono panels wired in parallel. The solar panels unhooked to the controller show 20v but when connected to the controller, the panel voltage drops to 12.9v and 0A reported on the VictronConnect app.
Got it working. Yesterday panel v was over 5v above battery but didn’t turn on. Rewired the panels today to 2 sets in series and those sets parallel. So roughly 35-40 volts at 200w. Not wired totally series due to current wire and connector lengths. The charger now works fine. Thanks for all the comments.
Suspect that you need more sun.
you maybe better putting all 4 panels in series and raising input the voltage to 80V (presuming that you dont have shading issues
another test would be to disconect the PV and then short the PV neg and pos and with a clamp meter measure the amps in good sun it should be about 20 amps in your current config if they were in series then 5 amps
Also, check your panel polarity. Especially, *Don't* rely on wire markings to tell you - my own panels have red bands on the -ve wires - I don't know why they do that??
The MPPT needs at least 5V above the battery voltage from the PV-panels to start charging.
After charging started you need 2V more then battery voltage.
In your case 18V.
As @Paul B sad you should connect the panels in series instead of parallel.
