Switches and fuses

[Ip485]

For some reason i am hesitating over the switching for panels.

The panels are 330w, nominal current a shade under 6 amps, nominal 54v. The panels run to an outback controller - flexmax 80. Whats a sensible rating for the switch for each panel, and should the switch be fused?

The contoller charges a 800ah battery bank, with definitely 2 and possibly three panels wired in.

Again what would be a sensible rating for the switch between controller and batteries and should it be fused?

I am not comvinced of the need for fusing all the switches?

[GordMay]

Greetings and welcome aboard the CF, Ip485.

[skipmac]

The output from the panels is fairly low so as long as you have wiring large enough to handle the panel output a fuse is not necessary for the panels. BUT, the wire will be connected to the battery and if the wire shorts out that will short the full battery output.

I would fuse the charger connection to the battery and not the switch that controls the panel output. My preferred method for fusing connections to a battery is a Blue Sea Systems battery terminal fuse.

[smac999]

fuse the controller wire close to the battery. I don't know why you need switches.

I would probably fuse each panel near the controller just for reliability. that way if one panel wire shorted. it would only take out that fuse and the other panels would still be charging. otherwise it would take out the main fuse and stop all. and if you wanted to stop one panel you could pull the fuse. don`t see the need for switches.

[mariner36bob]

I'm switching a single 8A panel with a 15 amp SPST switch at the helm. The switch (and a fuse) will be on the battery side of the controller. At the helm was the most logical location for us. When at the helm, prior to turning the ignition key, I can turn Off the solar panel feed and charge from the alternator charge. When time to sail, turn off ignition and turn on Solar. I've read on this forum of alternator cycling, due to it sensing the solar feed, potentially causing premature failure of the alternator. Our alternator is very old so not causing it undue stress was/is a consideration.

[mitiempo]

The fusing close to the positive post is necessary. The switch is not needed.