solar panel blowing fuse

[cory]

I have a VW Solar Panel that I have been using for the past few years to keep my battery topped up in the cold winter months.
Recently is has started blowing the fuse whenever I plug it in.
Anyone have any input on why it may have started this new trick and/or what I can do to remedy the situation ?

Thanks
Cory

[jtanguay]

contacts shorting out? is it all corroded? i would try other things in the cigarette plug to see if they blow the fuse a well.  if not then its your solar panel  :wink:

[cory]

The contacts are in great condition. My cell phone charger doesn't blow the fuse...but it is drawing current not feeding it. That seems like it would make a difference but I am not sure. My first thought was that the panel was faulty but I couldn't reason why it would fail out of the blue.

[MaxHedrm]

Too sunny? That's really weird. I would imagine in order cause that it would have had to have shorted or something.

[jtanguay]

does it blow the fuse right away?  what rating is the fuse?

[cory]

It does blow right away. It is a 15 amp fuse. The radio works fine, which is on the same circuit. Plug in the panel and...done.

[jimfoo]

Probably a short in the cord or plug.

[BlackTieTD]

ya a short in the solar panel electrics

[Darkness_is_spreading]

It will be one of two things.....   Check the continuity of the cables, then check the input to the board, there will be a zener diode or voltage regulator,  and in this case you may have an internal short.  Connect a scope to the ouput of the solar panel and see how clean the signal is, or measure the output with a volt meter, it should stay constant, then add a load (under rated load of solar panel) and see what the voltage level is at.

[bigblockchev]

I say short in the plug itself. Does the solar panel actually produce voltage, check the output with a volt meter. I'm not sure but I think the panel doesen't have much electronics associated with it maybe a diode maybe not. Just DC output and not much of that a few watts maybe 500ma to 1A output current in bright sun. Not much help in charging if it blows fuses. Cheers Dan

[silvertdi]

That's really wild.  I guarantee that solar panel is not putting out greater than 15 A.  Probably a few milliamps.  Is the wiring to the fuse box stock, or has it been spliced into?

[cory]

I appreciate all of the insightful responses I got with this issue. Yesterday while I was waiting for my wife to fill up our growler at the brewery I thought I would see if the cigarette lighter would replicate the issue. So I popped in a new 15 Amp fuse and while I was grabbing the lighter from its typical home in the ashtray, I noticed a strange shine in the bottom of the cigarette plug.
I poked a pen down inside for further investigation and got some pretty sparks. I grabbed my flashlight for better light and could see that  a small key ring had fallen down into the hole and was seated nearly perfectly at the bottom of the plug. I tried again with the pen to get it out, more sparks and another blown fuse. After the fuse went I grabbed the ring and inspected it. It had 4 burn marks on it...funny that is the number of fuses I had gone through.
Anyway just wanted to let you all know, problem solved. Thanks again for all the input. It was an internal short, of a bizarre variety.

Cheers
Cory