Two pole (?) disco with only 1 single fuse slot in the middle?

[Jraef]

I've installed something similar as a single pole DC disconnect on a functionally grounded system in the past. But what we're looking at makes no sense as a 2-pole AC disconnect to match the accompanying drawing.

On some switches you get to raise the voltage rating from 300V to 600V if you use the poles in series. A bit odd with a fuse in the middle though. I question if that's legit without seeing the label.

That’s exactly what it is: solar PV disconnect on the DC side, higher than 250VDC, so they have to use contacts in series to get the higher voltage DC rating, but you only need to fuse one side of the circuit. Doesn’t matter where the fuse is in that series arrangement.

 

[jaggedben]

That’s exactly what it is: solar PV disconnect on the DC side, higher than 250VDC, so they have to use contacts in series to get the higher voltage DC rating, but you only need to fuse one side of the circuit. Doesn’t matter where the fuse is in that series arrangement.

At least one switch I used in such a configuration required the two outer poles of the three pole switch to be used to achieve the 600V DC rating. So position might matter. Gotta read the label.