How do I know what size fixed panels I have on the roof without taking them off . Also how do I check if one of the panels , are not working.
Cheers Mick
Whenarewethere said
07:59 AM May 27, 2021
With ideal weather at the middle of the day. Measure the amps & voltage coming into the controller & calculate the angle of the sun & factor this in. Repeat a few times to average results.
The other option is measure the actual area of the solar cells themselves, not the overall panel, & use a conservative factor of say 130 watts per square metre. If the are new panels say 150 watts per square metre.
Whenarewethere said
08:04 AM May 27, 2021
Ideally they show be wired in, in such a fashion that you can measure each one individually, this could be wired in with individual switching. A DC clampmeter is a great tool to check everything.
I would measure the size of them and just look on the web for similar sized panels to get some idea of the power. Sometimes you might get a mobile to take a pic of the specs label by sliding it under.
If you want to know if one is not working then assuming you have an indication of the power or amps of them all, get out in the bright high sun, cover the panels with thick blankets or similar, and uncover one at a time and see how they compare. Do not fall off the ladder though.
Obviously a clamp meter would be easier but only if the person who wired it left the wires available to get around individually and I have not seem that often.
Jaahn
-- Edited by Jaahn on Wednesday 2nd of June 2021 02:43:42 PM
Peter_n_Margaret said
03:03 PM Jun 2, 2021
Comparing them to others on the market is risky because many are severely overstated (and fraudulently so).
Unless they are particularly good (or bad) they will be about 150W/m2 under test conditions.
In full sun they will produce about 70% of that.
Covering or clamp meter or disconnecting one at a time is the only way to get a reasonable actual.
Cheers,
Peter
How do I know what size fixed panels I have on the roof without taking them off . Also how do I check if one of the panels , are not working.
Cheers Mick
With ideal weather at the middle of the day. Measure the amps & voltage coming into the controller & calculate the angle of the sun & factor this in. Repeat a few times to average results.
The other option is measure the actual area of the solar cells themselves, not the overall panel, & use a conservative factor of say 130 watts per square metre. If the are new panels say 150 watts per square metre.
Ideally they show be wired in, in such a fashion that you can measure each one individually, this could be wired in with individual switching. A DC clampmeter is a great tool to check everything.
Hi Mick
I would measure the size of them and just look on the web for similar sized panels to get some idea of the power. Sometimes you might get a mobile to take a pic of the specs label by sliding it under.
If you want to know if one is not working then assuming you have an indication of the power or amps of them all, get out in the bright high sun, cover the panels with thick blankets or similar, and uncover one at a time and see how they compare. Do not fall off the ladder though.
Obviously a clamp meter would be easier but only if the person who wired it left the wires available to get around individually and I have not seem that often.
Jaahn
-- Edited by Jaahn on Wednesday 2nd of June 2021 02:43:42 PM
Unless they are particularly good (or bad) they will be about 150W/m2 under test conditions.
In full sun they will produce about 70% of that.
Covering or clamp meter or disconnecting one at a time is the only way to get a reasonable actual.
Cheers,
Peter