Circuit Protection On Interconnects

[ammauric]

Our designs at my company regularly incorporate a power distribution panel (PDP) and several other panels.

I have seen application of CBs to protect outgoing power (120VAC) from the PDP and then in the secondary enclosure on the same circuit another CB on the incoming power.

Occasionally when reviewing other drawings, I'll find a design that only has the CB in the PDP, and in the secondary enclosure will go right to devices.

It seems logical to me to design with a CB before and after the interconnect, but I'm wondering if there is any code in the NEC/NFPA79 that calls this out.

 

[tom baker]

If this is listed equipment
1. The NEC does not apply to the internal wiring of listed equipment
2. The NEC is an installation standards , we electricians just wire the line and load.

I am not familiar with what you describe. Perhaps a picture would be appropiate