What went wrong on my Solar panel?

[guruji]

What could be that went wrong with my 40w solar panel? It's only giving me 0.18amps with 15.55v. Is it maybe connections?
Any suggestions?
Thanks

[DreamThinkBuild]

Hi Guruji,

What is the rated open current and open voltage? How long are the cables and what gauge? If the panel has been outside for a while make sure the connections are clean no rust or oxidization (yellowing/white powder coloring on the clips).

I have one 15 watt panel that I accidentally shorted out for the whole day, doh!. The panel puts out voltage still but very little amps now, the panel is essentially damaged. Did anything happen to short your cells out(moisture, wiring)?

Sometimes all it takes is one bad cell to bring down the whole series. If you have access to the cells check each one individually and see if a bad one is located in there.

If it's a commercial panel look for cracks in the glass or peeling in the plastic film around the edges, this will allow moisture in and do damage. Look for dark discoloration or pits in between the lines of solar cells to see if there is water damage. If you notice any water inside take it in the house away from the sun and see if you can dry it out, may have to leave it in a dry, dark room for awhile keep checking the output every other day. Then try to repair the any cracks with a silicone window sealer if it starts to stabilize. It's better to catch this early.

Some of the bigger panels have blocking diodes, check that to see if it's bad. They are sometime buried in a silicone, where the wires come out, if you take an Exacto knife you can carefully cut the material out to get to the diode.

[guruji]

Hi Dreamthink thanks for response. Today I was checking my cells but still a bit unsure what's going on. I have 35 cells in it and it's giving me around 17v at 1.10 amp. When I bought the cells the guy told me that each cell is 1.2w. Checking a cell it gives 0.55v and 0.15amp on both sides. Amperage I think should be 0.5amp atleast on both sides to give 1.2w.
Am I calculating wrongly?

[DreamThinkBuild]

Hi Guruji,

The cell you checked was in full sunlight? giving off .55v@150ma ? May have to check each cell individually if all 35 are giving around the same reading then the cells are rated wrong.

If you have some that are near what is rated then some bad ones are bringing down the chain. Have to remove the bad ones and replace them.

[guruji]

Hi Guruji,

The cell you checked was in full sunlight? giving off .55v@150ma ? May have to check each cell individually if all 35 are giving around the same reading then the cells are rated wrong.

If you have some that are near what is rated then some bad ones are bringing down the chain. Have to remove the bad ones and replace them.

Hi Dreamthink

Yes I think these cells that I bought were not efficient as advertised. They were advertised as 1.2w but they only give about 0.25w in full sunlight
Yesterday I checked a cell that was reserved but still giving same readings.
Yes I checked cell by cell and changed two but still only about 18w is coming out.
Thanks