Solar panel fuse size

[Corribee72]

Hello all, I am putting in a replacement solar panel and will be putting an inline fuse to the positive battery wire, there isn't currently one in place. It's a 25w panel, so would a 5amp inline fuse be sufficient?

Also, the current wiring has the negative from the solar panel to the regulator and the positive from the panel connected directly to the battery, is this setup ok. I've had one fire already and really don't need another! Many thanks.

 

[lpdsn]

Hello all, I am putting in a replacement solar panel and will be putting an inline fuse to the positive battery wire, there isn't currently one in place. It's a 25w panel, so would a 5amp inline fuse be sufficient?

Also, the current wiring has the negative from the solar panel to the regulator and the positive from the panel connected directly to the battery, is this setup ok. I've had one fire already and really don't need another! Many thanks.

I'd go smaller than 5A. I presume the panel is circa 18V so if it can put out 2A you've made a good bargain.

What's your controller? Most have both +ve and -ve going via the regulator.

 

[Richard10002]

like lpdsn, I'd have thought you would have +ve and -ve from panels to controller, (no fuse needed, but a switch can be convenient), then +ve and -ve from controller to batteries, with a fuse in the +ve, very close to the battery connection, (within 6in is recommended I think). The fuse is to protect the cable from overheating and catching fire, so anything over about 3A and less than the cable rating should be fine.

 

[VicS]

Hello all, I am putting in a replacement solar panel and will be putting an inline fuse to the positive battery wire, there isn't currently one in place. It's a 25w panel, so would a 5amp inline fuse be sufficient?

Also, the current wiring has the negative from the solar panel to the regulator and the positive from the panel connected directly to the battery, is this setup ok. I've had one fire already and really don't need another! Many thanks.

This sounds very strange. As said one would expect both positive and negative to be connected to the controller.

Tell us what controller you have. .... Is it a controller or something else ?

A 3amp fuse as close as possible to the battery connection will be fine. The wiring will hopefully have been sized heavier to minimize volts drop and for physical robustness.