EEVblog Electronics Community Forum

Electronics => Repair => Topic started by: metricscaleer on April 22, 2024, 04:18:08 am

Title: Hi newbie here!! Thanks for the add!! Question for anyone.
Post by: metricscaleer on April 22, 2024, 04:18:08 am

I was working on my camper van which has solar panels, a solar controller { 20 Amp MTTP } two 100AH deep cycle batteries, and an inverter. the solar panel and the battery in connections in the controller were really loos so I disassembled it and resoldered the pins that went through the circuit board and it looks I was successful, my question is when it tests for continuity on the battery + - I have it but i don't have it when I test the solar panel in + _ I was wondering if I should have continuity but i don't know
Thanks!!!

Title: Re: Hi newbie here!! Thanks for the add!! Question for anyone.
Post by: Shock on April 22, 2024, 11:49:16 am

Multimeter continuity/resistance/diode/capacitor functions are all for non powered circuits. Multimeters on these tests a apply it's own voltage/current to the circuit under test (so therefore polarity matters). If you think you may have a semiconductor/diode blocking current in your test you can try the diode function and or reversing your test leads to get the polarity correct.

So the inverter needs to be switched off and the power sources (solar panel/battery) fully disconnected/isolated. You can test one wire at a time if it's isolated at one end but you must be sure it has no current running down it.

It's best to test powered devices or voltage sources (in this case) with the dc voltage function across both conductors and dc voltage drop measurements down individual conductors. This is the "live" way to determine if there is a high resistance (bad) connection.