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When I connect my PV (-) and (+) to my MPPT 100/50, my voltage immediately drops from 41V to 29V. This of course keeps the voltage too low for my 28V system to charge, so the charger stays "off".
I've replaced all MC4 connections between the panels and the MPPT just to be safe, yet the exact same voltage drop happens right when I connect to wires to the MPPT controller.
Firmware is updated.
Any thoughts on a potential solution?
It is normal for panel voltage to drop from VOC under load.
You basically need at least one more panel to work a higher string voltage thus taking advantage of the mppt.
The one panel setup works better with a pwm controller.
The voltage drop is normal under load, but yours seems slightly higher than what I would expect.
What is the rated voltage for maximum power for your panels?
How long are the wires from the PV panels to the MPPT and what size (cross-section area) are they?
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If you double the number of panels in series:
82V is probably fine, but if your string Voc gets too close to 100V, you have to check the maximum voltage for the lowest temperature you can have there.
