Hedges
I See Electromagnetic Fields!
- Joined
- Mar 28, 2020
- Messages
- 20,855
took DMM reading at pv disconnect red lead zero black lead fluctuating up to high 400's (neg polarity)
close breaker at disconnect, go to basement turn on/reconnect Sunny Boy
Definitely positive grounded.
Find out if your new panels are best off positive grounded (negative biased) or negative grounded (positive biased) to avoid PID.
Manufacturer may claim "PID free" (I didn't see mention on data sheet), but that just means reduced degradation.
Ask them which grounding configuration is better. Ask them about P vs. N type silicon (doping of wafers) and implant (to make P-N junction). From that should be able to figure it out even if they don't clarify grounding.
Grounding in the better polarity should eliminate PID, one less thing to reduce output over time.