Switches for solar panels

[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. Whats a sensible rating for the switch for each panel, and should the switched 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 contoller and batteries and should it be fused?

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

 

[VicS]

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. Whats a sensible rating for the switch for each panel, and should the switched 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 contoller and batteries and should it be fused?

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

The most important fuse is the one connecting the controller to the battery bank. That should be rated to protect the wiring.

Id think that would be the only fuse necessary.

The switches must be rated to carry the maximum current they will be subjected to but they must also be suitable for DC.

But why all the switches ?

Why 54 volts ?

 

[William_H]

54 volts or perhaps more like 60volts would be the result of 3 nominal 12v (system) panels in series. This is fine for a MPPT controller to give 14 volts for a battery system.
I don't know the merits of 3 panels in series or 3 panels in parallel only less voltage drop in wiring with less current from the panels.
It is possible the controller can take more power at higher voltage but not the high current of parallel panels. Because the switching transistors have to carry the current.

As Vic says you need to fuse the wire from controller to battery because any short here or in the controller can take a high current from the battery to overheat the wiring. (fire)
It is unlikely that the current from the solar system would be enough to overheat the wiring in a fault.
Regarding switching I can't imagine why you would want a switch to the solar charging. You don't want to switch it off but it might be switched off inadvertently. A removable fuse would be adequate if you need to isolate the system. good luck olewill