How do I test a solar panel ?

[ptc]

I have a panel that drives a Bilge pump
Johnson 12volt dc 1.4 amp.
the pump or the panel have packed up.
pump is a sealed unit
how can i test the panel ?
i do not want to damage it by going about it the wrong way.

[echnidna]

disconnect the pump from the solar cell.
there should be a voltage at the solar panel when the sun shines on it,
possibly in the range 16 to 20 volts. If theres no voltage the cell is u/s

connect the pump to a 12 volt battery and it should work, if it doesn't the pump is u/s

[RETIRED]

The battery might be U/S too.

[glock40sw]

Stick you tongue on the bare wires and see if you get a jolt .

[rrich]

Stick you tongue on the bare wires and see if you get a jolt .

Oh, that would hurt!

DAMHIKT

[ptc]

Bob
I think the pump is U/S.
i do not have a voltometer
any other way to test the panel.?

[DavidG]

Stick a 12 volt light bulb (car) across the panel wires. It should light up. (Not headlight)

[ptc]

David
will get bulb on Monday and try it
thanks for info.
did not want to damage the panel
was not sure how to go about testing.

[RETIRED]

It s near impossible to destroy a panel bar smashing or shooting it witha shotgun (DAMHIK).

Open or short circuiting them will do no damage.

PTC, you need at the most a tail light globe and be prepared for it to "blow".

[mixin]

Might be an idea to cover 1/2 to 3/4 of the panel before testing it with the globe.

If it only glows dull, then uncover it a bit more.

At least that way you can 'limit' how much unregulated wattage you'll pump into the bulb, and hopefully not blow it in an instant - although that flash as it blows will tell you that the cell is working well!

[ptc]

Tested panel with tail light bulb(12volt)
It is working.( Very bright)
Thank you all for the help.
Can now get a new bilge pump.

[journeyman Mick]

Just snap the strainer off the pump (if it has one) and check that it isn't clagged up with hair or other junk which prevents it from turning. It may be too late already for it, but it's worth a look.

Mick

[ptc]

Mick its a bilge pump. Motor is a sealed unit and rotor(impeller) turns freely.
No sign of gunk etc.
this is my second pump in 6yrs.
thanks for advice

[journeyman Mick]

The smaller plastic Whale and Rule bilge pumps have snap on plastic strainers. Jammed impellor is a common problem. Not sure what your set up is or type of pump, but that's usually the first thing to check. So it sounds like either your pump is burnt out or perhaps there's a break in ther wiring feeding it.

Mick