Fusing solar panel junction

[SanDiegoChip]

Hi,
We just wired up our buss that goes to our solar controller. We added one more panel than the picture shows. Any way there are two wires from each panel. One neg and one positive and they go to each side of the buss.
My question is do we need a fuse on each solar panel positive cable? They are #10 and would be a 15 amp fuse.
We do not want to go through the time and expense of fusing each panel. Of course if needed we would do this to avoid a fire but is this really needed?

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Thanks,
Chip

[SanDiegoChip]

Sorry this post was supposed to go to "Electrical".
Chip

[mitiempo]

I would fuse them - individually.

[AdamLein]

I seem to remember reading advice of the form, "fuse any wire that goes to the battery + post, as close to the post as possible." So assuming the + side of your bus goes directly to battery +, that's what I would fuse.

Probably I read it in Don Casey's "Sailboat Electrics Simplified."

p.s. that said if you have, say, a 9A fuse on the bus's + wire and each panel puts out 3A, then an overload in any of the panel wires won't necessary blow the fuse. Of course, it's not clear to me, short of, well, a short, how a panel wire might overload.

[pdqaltair]

...we have to guess.

If they were small, under the capacity of the panel or connecting wiring, I think not. But if those are large panels, and I assume they are, individual fuses may be needed. And there will certainly be a fuse between the controller and the battery.