Depth difference between wireway and service equipment

[rjk_cmh]

I'm planning an installation that will have equipment with a few various depths, mounted over (and connected to) a wireway. Is there a requirement that the equipment must not overhang the wireway, or vice-versa? I recall hearing about a limitation of 6-inch difference in depth, but it wasn't clear which part of the installation was allowed to protrude.

Here's the specific example:
A transfer switch having a panel depth of 14 inches will be installed adjacent to a service panel with a 5 inch depth, and a wireway will be installed underneath the transfer switch. The end of the wireway will connect to the side of the service panel on one side. So only the transfer switch is installed over the top of the wireway. I was planning to use a 6x6 wireway based on my box fill calculations.

The 6 inch would protrude 1 inch farther than the service panel, and 8 inches less than the transfer switch. Do I need to bump up to an 8x8 wireway so that I'm within 6 inches of the transfer switch depth? Is there any reason that having the transfer switch 9 inches deeper than the service panel would be a problem either?

 

[infinity]

The wireway is under the transfer switch so it is not in the working space of the transfer switch. If it were in the working space you would be allowed up to 6" past the front edge of the TS.

Welcome to the Forum.

 

[rjk_cmh]

The wireway is under the transfer switch so it is not in the working space of the transfer switch. If it were in the working space you would be allowed up to 6" past the front edge of the TS.

Welcome to the Forum.

Thank you very much! It makes sense, I just wanted to be sure.

 

[Carultch]

I'm planning an installation that will have equipment with a few various depths, mounted over (and connected to) a wireway. Is there a requirement that the equipment must not overhang the wireway, or vice-versa? I recall hearing about a limitation of 6-inch difference in depth, but it wasn't clear which part of the installation was allowed to protrude.

Here's the specific example:
A transfer switch having a panel depth of 14 inches will be installed adjacent to a service panel with a 5 inch depth, and a wireway will be installed underneath the transfer switch. The end of the wireway will connect to the side of the service panel on one side. So only the transfer switch is installed over the top of the wireway. I was planning to use a 6x6 wireway based on my box fill calculations.

The 6 inch would protrude 1 inch farther than the service panel, and 8 inches less than the transfer switch. Do I need to bump up to an 8x8 wireway so that I'm within 6 inches of the transfer switch depth? Is there any reason that having the transfer switch 9 inches deeper than the service panel would be a problem either?

It's the other way around. The wireway, or raceways in general, are permitted to extend up to 6" in to the working space of equipment that requires it. So it is OK to have a 12"x12" wireway under, over, or adjacent to a 6" deep piece of equipment.


There is no requirement that the wireway be close to the depth of the equipment, if the wireway is nowhere near as deep as the equipment. You can have a 4x4 wireway connected to 12" deep equipment, as long as you can fit the connections you need to fit.