Low performing Solar Panels

[LONG_KEELER]

I have an array of 4 fixed panels totalling 75w fitted where possible on a 26' boat. Most are under the boom but they serve me well in summertime.

Joined in parallel, crimped together to head shrink terminal then a single cable to a deck gland.

Because of variable sun/shading I am not sure if they are all working at times or some have simply failed. They are cheap to renew.

Can anyone suggest a simple wiring system where I can test individual panels in situ .

Thanks in advance.

 

[Graham376]

Can anyone suggest a simple wiring system where I can test individual panels in situ .

To test individually, you will need to disconnect each one from the other panels. Maybe get rid of the crimps and use Wago connectors in waterproof box.

 

[peteK]

Quick test is to cover the panels and leave one uncovered and check the output and just test each one at a time.

 

[noelex]

A clamp on multimeter will show the current each solar panel is contributing without disconnecting any wiring.

They are not expensive and a useful tool to have on a boat. Make sure whatever unit you buy will measure DC currents via the clamp.

 

[William_H]

The real test for a solar panel is the short circuit current. I presume you have 20w panels which should give 1 amp short circuit using a multimeter on amp scale. One amp being maximum for the panel facing the sun and in good sunlight. As said try covering all but one panel if you don't want to separate the wiring. Obviously even a good panel will be a lot less current in bad weather. ol'will