Multiple Disconnects, one above the other

[lbergero35]

I have a space limitation that requires 2 disconnects to be mounted on the wall. The only option is to mount one above the other. Is this in violation of the NEC?

 

[augie47]

No violation as long as both meet other Code requirements (110.26, 404.8, etc)

 

[infinity]

I agree we stack them whenever necessary. Something like this although the wireway is a violation.

 

[LarryFine]

Are you talking about merely stacked, or sharing conduit, too? As long as they're not service discos, it's all okay.

Something like this although the wireway is a violation.

Why, because of its depth?

 

[infinity]

Are you talking about merely stacked, or sharing conduit, too? As long as they're not service discos, it's all okay.
Why, because of its depth?

Yes, the depth of the wireway extends past the front of the disconnects which would be an issue for the three between the wireway and the panel.

 

[PaulMmn]

You just use the Hot Stick to switch those 3...

 

[Carultch]

Yes, the depth of the wireway extends past the front of the disconnects which would be an issue for the three between the wireway and the panel.

The proper solution to meet the NEC wording, is to build-out a structural backing of the three disconnects in the middle, to make them coplanar with the neighboring equipment. It appears the installer of the 3 disconnects to the right, already did this. I don't read a strict requirement for narrow equipment sharing the 30 inch working space to be coplanar, but I also don't see a specific exception to allow variation within reasonable limits.

Given that it is OK for wireways above and below to stick out up to 6" beyond equipment, I don't really see the real life consequence of a similar wireway being on the side. I see no difference in the practical issue, between differing depth equipment to the sides, and differing depth equipment to the top and bottom, for the same difference in depth.

To answer the OP's original question, "dedicated space" is "dedicated" to the electrical installation, rather than just that piece of equipment. It is OK to mount electrical equipment and raceways above and below, where dedicated space is required. It is foreign systems, like plumbing and HVAC, that are not permitted in dedicated space, for equipment requiring it.

 

[Eddie702]

@Carultch
Not sure there is anything in the code related to depth. You can't put a transformer on the floor under a panel although that used to be common practice and that isn't foreign equipment

 

[petersonra]

@Carultch
Not sure there is anything in the code related to depth. You can't put a transformer on the floor under a panel although that used to be common practice and that isn't foreign equipment

sure you can. The transformer just cannot be in the working space.

 

[Carultch]

@Carultch
Not sure there is anything in the code related to depth. You can't put a transformer on the floor under a panel although that used to be common practice and that isn't foreign equipment

Depends on the transformer. If it is more than 6 inches in excess of the panel's depth, which any serious sized transformer would be, the transformer would block access to the panel. The panel being mounted to the side of the transformer, is the proper way to do it. However, if we are talking about a miniature transformer, possibly 5 kVA or less, that is the same depth of the panel, you certainly could put it directly above or below it.

You could build-out a cantilever structure to suspend the panel so it is in-plane with the front of the transformer's depth, and meet the intent of this rule. This thread shows an example of how to do it. You of course would want to leave enough clear space to lift the transformer out of position, and replace it when necessary.

Disconnect over transformer?

I am trying to solve a wrong voltage issue on a CHP unit (should be 208V, arrived 480V). I have limited space to put a step down transformer. Clear space requires that I have 36" in front of the secondary (208V) disconnect. Is there any reason I cannot mount the disconnect above the transformer...

forums.mikeholt.com

 

[charlie b]

To answer the OP's original question, "dedicated space" is "dedicated" to the electrical installation, rather than just that piece of equipment. It is OK to mount electrical equipment and raceways above and below, where dedicated space is required. It is foreign systems, like plumbing and HVAC, that are not permitted in dedicated space, for equipment requiring it. (my added emphasis)

And to take this one step further, disconnects are not on the list of equipment that requires "dedicated equipment space." That requirement only applies to switchgear, switchboards, panelboards, and MCCs.

 

[kwired]

working space and dedicated equipment space are not the same thing.

Poor angle in the photo to tell if those disconnects are more than 6 inches behind the front of the wireway, but if wireway is that deep the simple solution would be to somehow bring the switches forward when mounting them.

If they are fused switches, they probably should require working clearances, if they are non fused switches they seem pointless unless maybe they are not supplied by the panelboard next to them and are just local disconnecting means for nearby equipment.