Three panels in a T

[Tom Bradford]

Hi.

I want to connect three solar panels in parallel.

All the idiot's guides I've seen for this show the panels chained with the connection to the controller off the last panel in the chain, but is it possible/permissible to take the connections to the controller from the center panel without loss of amps; i.e. [ + > + < + ] with the + connection to the controller from the center >+< and ditto the negative?

Thanks.

[inetdog]

Hi.

I want to connect three solar panels in parallel.

All the idiot's guides I've seen for this show the panels chained with the connection to the controller off the last panel in the chain, but is it possible/permissible to take the connections to the controller from the center panel without loss of amps; i.e. [ + > + < + ] with the + connection to the controller from the center >+< and ditto the negative?

Thanks.

Electrically it does not matter which of the two arrangements you use except for the wire size needed in each run.
But I would say that more people run a wire from each of the three panels directly to a combiner box with fuses, which is not either of the options you describe.

If you have more than two panels or strings in parallel you must fuse each string independently. If you are going to fuse them independently, there is no particular reason to daisy chain the wiring. You would need to have a fuse right at the terminals of each panel, before the point where the wires come together. Hard to install a fuse holder there and hard to get at.

[Tom Bradford]

But I would say that more people run a wire from each of the three panels directly to a combiner box with fuses, which is not either of the options you describe.

If you have more than two panels or strings in parallel you must fuse each string independently.

None of the examples or How-tos Google produced for me dealt with fuses - certainly not fuses between panels in a daisy-chain.

Why do you fuse panels anyway? I'd thought you could short-circuit a panel without damage, but usually put a breaker between the panels and controller in order to be able to disconnect them from the system.

Anyway, PV combiners are something else to mug up on now. Thanx.

[Sunking]

Why do you fuse panels anyway?

For a single string it is not required. Otherwise it is a code requirement. Even with a single string it is good practice to use a OCPD in the event of a backfeed fault.