Scratches on Solar Panel below the glass
Just got this panel from Solar Blvd and it has these two scratches below the glass. Should I be concerned?
Forum Discussion
You can check the panel for Voc and Isc compared with its rating to see if it is ok.
Aim it (tilted and pointed) at the sun when sun is high and in blue sky. Put the voltmeter across the pos and neg at the junction box to test Voc.
If the panel's Isc is rated below 9 amps (leave some margin from 10a meter limit) you can switch to amps and measure Isc.
You have to adjust your panel aiming while checking the meter to find where you get the highest readings. I usually find Voc reading a bit lower (20 instead of 22 say or 34.5 instead of 37) than rated, but Isc is close to rating.
When the panel or even one cell is part or all shaded, or if you have a damaged cell, the measured Voc and Isc will be a lot lower. A bit lower just means there is some haze in the blue or whatever.
Aim it (tilted and pointed) at the sun when sun is high and in blue sky. Put the voltmeter across the pos and neg at the junction box to test Voc.
If the panel's Isc is rated below 9 amps (leave some margin from 10a meter limit) you can switch to amps and measure Isc.
You have to adjust your panel aiming while checking the meter to find where you get the highest readings. I usually find Voc reading a bit lower (20 instead of 22 say or 34.5 instead of 37) than rated, but Isc is close to rating.
When the panel or even one cell is part or all shaded, or if you have a damaged cell, the measured Voc and Isc will be a lot lower. A bit lower just means there is some haze in the blue or whatever.
