solar panel query

[deep denial]

I have a soler panel from 2001, a small one rated at 10w. I have heard that you need a diode to stop backflow of electricity at night. Is it likely that a diode is included in the circuitry of the panel, and how do I test to find out? thanks for any advice

 

[simonfraser]

very likely it has a diode.

measure the resistance with a multimeter, should be low in one direction and high in the other, if it has a diode.

 

[samwise]

Need to know the make really, but I would think it unlikely it was in the panel. Technology i n this area has moved on quite a bit since your kit was made. Have a word with the people at Barden they are very helpful.

 

[dazautomatics]

If it has a plastic box on the back, check for the resistor shaped component fitted over the + /- connections.
And also see if it discharges when the light goes.
Darren

 

[William_H]

I think the simplest way to determine if it has one (or needs one) is to connect the panel through a multimeter on current range. You should be able to measure around 300 milliamps in bright sun gong into the battery. If you cover the panel ton exclude light this current will drop to zero and you should check at the lowest range you have ie 200microamps and still see no current in the reverse direction.

I have checked cells (no diode) and not found any reverse current but most manufacturers fit one anyway. good luck olewill