Solar Panel wiring question

[davidmh]

I have small 30W rigid solar panel I use for battery charging, one of the connectors has an intermittent fault. i am about to change the connector. The panel is at home in UK. What panel voltage will I see on a multimeter indoors under normal house LED lights. A quick check gave 5.1 V. Is this a reasonble fiqure? If I can get some sun in the next few days and take the panel outside what voltage should I get, I think it should be around 20V is that correct?

David MH

 

[noelex]

Solar cells are very good at generating voltage (but very little current) under low light levels. However, I still would not expect much voltage if there was no natural daylight, so 5V is perhaps not so terrible.

The test is going to come outside. Even in overcast conditions, you should see 17+V and with direct sun around 20V, as you stated.

Good luck with the repair.

 

[AngusMcDoon]

Inside impossible to say because some panels are not sensitive to the frequencies of light put out by LED lights (which is only a few narrow bands of frequencies). Outside twenty something volts. It may say on a label on the back. When open circuit and just measuring voltage cloudy bright at midday should give you that voltage.

 

[William_H]

Yes probably ok under artificial light. However more definitive test in good sun light is to connect an amp meter directly across output. Should get 1 to 1.5 amps through a short circuit. As you say a voltage of 19 to 20v no load is good. ol'will