Are fuses for solar kit a good idea?

[LeftyDale]

I am adding a Renogy solar kit to my nearly finished teardrop. The kit has a Renogy 100 Watt, 12 Volt, Black Division Lightweight Monocrystalline Solar Panel and a Renogy New Edition Voyager 20A PWM Waterproof Solar Charge Controller. I bought the 20 amp controller since I may want to add a second solar panel after I install a 12 volt cooler. My electrical system is only 12 volt, there is no 120 volt. I plan on running the wires from the controller to the main fuse panel, which is also where the smart charger plugs into when I need to top off the batteries at home. No fuses or fuse holders came with the Renogy solar kit. Should I provide a fuse on the positive wire between the panel(s) and the charge controller? If so, what size? Should I provide a fuse on the positive wire between the charge controller and the main fuse panel? If so, what size?

[lfhoward]

Here is the best explanation I know of:

[Capebuild]

Attached is a snap shot of what I did.... adding a 30 amp fuse before the charger.
John

[LeftyDale]

Thank you lfhoward and Capebuild for your replies and comments. The video that lfhoward linked was very informative. He seems to know what he's talking about. Initially I will have one 100 watt solar panel, and in the future possibly two wired in parallel. I purchased a Y connector from Renogy to tie the two solar panel feeds together. My plan now is to install a 10 amp fuse in the 10 AWG wire which runs from the solar panel to the Y connector. When and if I install a second panel, I would do the same on that wire. That will limit the current in each of those wires to 10 amps, which should limit the total current flowing to the controller to 20 amps. Capebuild, I like the switch you put in. I also would like a switch to shut off the power from the solar system so I can work downstream without having the system charged. As far as location of the switch, I am thinking of putting that switch between the controller and the main fuse block so that when I shut the solar system down in the garage I'm not getting any parasitic loads from the controller. I will also put a 20 amp fuse between the controller and the main fuse block. That's where I'm at so far anyway!

[LeftyDale]

Resurrecting an old post of mine. I FINALLY got around to installing my solar panel system. Yes, it's been in my garage for a over a year. I have the system set up for two panels but only have one installed now. I will see if that's enough before installing the second panel. I put a 10 amp fuse and a switch between the solar panel (100w Renogy monocrystalline) and the 20 amp Renogy Voyager controller. There is also a 20 amp fuse between the controller and the main panel. The switch (on the solar panel side of the controller), which is receiving 22 volts is set up with a small LED light which indicates when the switch is on. I kept blowing the 20 amp fuse between the controller and the main panel and I believe it is because the ground wire for the switch may be back-feeding 22 volts into the main panel. Does that make sense?

Is the best solution to swap out the switch with one that doesn't have the indicator light (therefore no ground wire)? I would be happy with a simple toggle. This switch would also need to be rated for something more than 22 volts and 20 amps. I've looked around and can't located one. Where is a good source for that?

[MickinOz]

I would be happy with a simple toggle. This switch would also need to be rated for something more than 22 volts and 20 amps. I've looked around and can't located one. Where is a good source for that?

50 Amp 24V truck toggle switches are $10 on Ebay.com

[LeftyDale]

Thanks MickinOz, I bought the toggle switch without the indicator light. That eliminates the ground. I think my problem was running the ground to the main control panel ground instead of tying it to the solar panel ground. Eliminating the indicator light eliminates that uncertainty. Thanks again!