Working Clearance

[Keith Millhollin]

The elctrical engineer on my project is claiming that equipment handles are not calculated in clear spaces for equipment and panels. The condition is a 120/208v panel next to an ATS at a 90 degree angle. We have clear floor space, but the handle for the ATS projects approx. 3" into the area. I feel that clear space means just that. Any help?

 

[Hendrix]

The elctrical engineer on my project is claiming that equipment handles are not calculated in clear spaces for equipment and panels. The condition is a 120/208v panel next to an ATS at a 90 degree angle. We have clear floor space, but the handle for the ATS projects approx. 3" into the area. I feel that clear space means just that. Any help?

If the doors can be opened 90 degrees, it might be ok.

 

[pfalcon]

Mu (Pronounced Moo like from a cow) [The correct answer to a question for which neither a Yes or No is truly appropriate].

On a very strict technical basis "Clear Working Space" means just that - no obstructions of any kind. The EE is not going to find or be able to quote any exception.

On a more humane technical basis the question also includes whether the 3" door handle is an actual obstruction or simply legalistic fulfillment of bureaucracy.

The EE needs to acknowledge that his "exclusion" for a door handle is nonsense. Then the two of you need to set pride aside and evaluate the real danger the handle presents.

The handle might need to be replaced with a flush handle or the panel might have to be moved. Either creates cost to your company. Or the handle may be located such that its intrustion into the volume is incidental and unimportant. Save the company a buck and leave it alone. You and the EE have to make the call. The default decision is to fix it.

 

[wasasparky]

When the cover is opened, doesn't it project into the clear area?
Nevermind the handle, now you have a bigger problem...

Measurements are to be taken from the edge of the enclosure...

 

[charlie b]

You are right. Nothing is allowed in the working space. If you visualize a box that is 30 inches wide, 36 inches deep, and 78 inches high (about the size of the cardboard box a refrigerator might be shipped in), you have to be able to set that box in front of the panel. The box can have its left (or right) edge flush with the left (or right) edge of the panel, or the panel can be anywhere in between.

But I understand that, in your case, you wouldn?t be able to get the edge of this box flush with the edge of the panel, because the box would bump into the ATS door handle. If that is right, you have both a code violation and an unsafe condition. The danger would be that if an electrician had the panel cover off, and was working inside, he or she might bump their shoulder against the ATS door handle. Their likely ?jerk reaction? to the bump could easily cause a hand to touch something unfortunate inside the panel.

Again, you are right. For the sake of the safety of a future worker, stand by your convictions on this one.

Welcome to the forum.

 

[wasasparky]

When the cover is opened, doesn't it project into the clear area?
Nevermind the handle, now you have a bigger problem...

Measurements are to be taken from the edge of the enclosure...

Not clearly reading the original question, I was considering the equipment facing each other...

We have a corner condition here, so now I say we have a problem.

(I should incorporate the "measure twice - cut once" method into my replies):smile:

 

[Keith Millhollin]

Thank you all for the input. It is a tight location with the panels at a 90degree angle. I will stand my ground and disagree with the EE.

 

[pfalcon]

When the cover is opened, doesn't it project into the clear area?
Nevermind the handle, now you have a bigger problem...

Measurements are to be taken from the edge of the enclosure...

You are required to secure the area from intrusion 110.26(B). That includes securing the second panel door in a closed position while you work on the first.