110.26(f)(1)

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charlie b

charlie b

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The following description is not the actual sequence of events. But it is the best way I can think of to describe the situation, without drawing a picture, which I cannot do, or taking a photo, and I have never been to this site.

Imagine a concrete wall that was supposed to be three inches thick. The electrical design shows some branch circuit panels surface-mounted onto this wall. All conduits (incoming power and branch circuits) will be entering from the top.

Now imagine that the concrete wall contractor made an error, and began to make the wall nine inches thick. The error was noticed when the wall was about 3 feet high. The rest of the wall, from that point to the ceiling, was built 3 inches thick. As you stand inside the room, and look at the wall, you see the wall coming up from the floor, then it recedes six inches, so that there is essentially a 6 inch lip (upon which you can set your coffee cup).

Question: Can you still mount panels on this wall, above the ?6 inch lip,? without having to use Unistrut to hold the panel away from the wall? 110.26(F)(1) says that the ?dedicated electrical space? extends from the floor. Well, if you mount the panel right up against the wall, then the space directly below the panel won?t extend to the floor. Rather, it will be blocked by the concrete wall.
 
I have to believe that this is a issue the panel never anticipated. I would talk to the inspector.That section appears to reference exuipment that might occupy the dedicated space. An argument might be made that the structure is not eq. Also does the wall compormise pthe buildings or service personal's safety ?
 
Convenient for the coffee cup, no so much for leaving the bottom of the gear. Not a violation.

No piping, ducts, leak protection apparatus, or other equipment foreign to the electrical installation shall be located in this zone.

Your wall does not meet the definition of equipment.
 
chris kennedy said:
Convenient for the coffee cup, no so much for leaving the bottom of the gear. Not a violation.

No piping, ducts, leak protection apparatus, or other equipment foreign to the electrical installation shall be located in this zone.

Your wall does not meet the definition of equipment.
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Ouch! I hate doing this,,but Chris, I disagree. The way read it, with my thoughts supported by Exhibit 110.23 in the Handbook (I know, Handbook is not gospel) the working space must be the depth of the equipment and extend from the floor.
That, added to the fact that the "extended" wall comes up 3 ft so it would practically prohibit bottom entry on any decently sized panel meeting the 6'7 rule.
I would have to say being the panels out.
 
I have to agree with Chris.
What about housekeeping pads? Do they not protrude forward of the gear roughly the same distance? 4 to 6 inches?
 
chris kennedy said:
Oh, you love it.:grin:

Handbook? Read on.
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\
O,K., I'll believe the Handbook picture and not the wording :grin:

Ignoring the Handbook, the actual wording says NO to me, but I have to and am giving Chris' comments consideration.
 
Gus, I fully agree it would be a very poor installation, given the wording of the NEC, IMO there is no violation.

(1) Indoor. Indoor installations shall comply with 110.26(F)(1)(a) through (F)(1)(d).

(a) Dedicated Electrical Space. The space equal to the width and depth of the equipment and extending from the floor to a height of 1.8 m (6 ft) above the equipment or to the structural ceiling, whichever is lower, shall be dedicated to the electrical installation. No piping, ducts, leak protection apparatus, or other equipment foreign to the electrical installation shall be located in this zone.
Exception: Suspended ceilings with removable panels shall be permitted within the 1.8-m (6-ft) zone.

(b) Foreign Systems. The area above the dedicated space required by 110.26(F)(1)(a) shall be permitted to contain foreign systems, provided protection is installed to avoid damage to the electrical equipment from condensation, leaks, or breaks in such foreign systems.

(c) Sprinkler Protection. Sprinkler protection shall be permitted for the dedicated space where the piping complies with this section.

(d) Suspended Ceilings. A dropped, suspended, or similar ceiling that does not add strength to the building structure shall not be considered a structural ceiling.
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The highlighted text is specific. Again, the wall in question fails to meet the NEC definition of equipment.
 
muckusmc said:
What about housekeeping pads? Do they not protrude forward of the gear roughly the same distance? 4 to 6 inches?
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In my opinion per the current wording in the code a housekeeping pad is a violation.

And as Don has pointed out the bottom plate and sometimes the top plate of a wall that a panel is flush mounted in are in violation.
 
chris kennedy said:
Gus, I fully agree it would be a very poor installation, given the wording of the NEC, IMO there is no violation.

The highlighted text is specific. Again, the wall in question fails to meet the NEC definition of equipment.
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So I have to assume I could build a 30" deep counter right under a panel?
 
I'm thinking "intent"...not my job, but..... The 6" extension would still "block" bottom entry. I'm going to stick with violation as an opinion....realizng there are others.
 
Working space if for:
1. Safety
2. Access to the panels
What if the panel was 6" deep, had a surface cover and the wall was furred out so now the panel front sits flush with the entire wall surface.
Is the working space measured from the back of the panel or front?
I maintain for safety its measured from the front.
Access to panels is less clear. But mike holt shows a graphic with a plumbing pipe in the wall below the panel a violation.
Sorry CB, I don't have a clear answer on this, yet.
 
I also think it is a violation. The intent of the rule is to permit access to the panel for the installation of conduit and cables. In this installation that access is blocked creating the violation.
 
don_resqcapt19 said:
I also think it is a violation. The intent of the rule is to permit access to the panel for the installation of conduit and cables. In this installation that access is blocked creating the violation.
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I expect my inspectors to inspect on the wording of the code not the intent.

I believe Charlies intent when starting this thread was to point out the deficiencies in the wording of this section.
 
chris kennedy said:
I expect my inspectors to inspect on the wording of the code not the intent.

I believe Charlies intent when starting this thread was to point out the deficiencies in the wording of this section.
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Chris,
I don't think we have to limit the obstructions to the things listed in the last sentence of the section. In my opinion that sentence is just clarification of the first one.
(a) Dedicated Electrical Space. The space equal to the width and depth of the equipment and extending from the floor to a height of 1.8 m (6 ft) above the equipment or to the structural ceiling, whichever is lower, shall be dedicated to the electrical installation.
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The wall is above the floor and in the space that is required to be dedicated to the installed electrical equipment. Also the exception seems to support my view of the wording as the suspended ceiling is not on the list in the second sentence. If only the things on the list were prohibited, there would be no need for the exception.

As far as the limitations of the wording, I agree that this section needs work. As Bob reported, I have previously stated that in my opinion this section prohibits the installation of flush mounted panels as the wall structure will intrude of the space that is required to be dedicated to the electrical installation.
 
don_resqcapt19 said:
I have previously stated that in my opinion this section prohibits the installation of flush mounted panels as the wall structure will intrude of the space that is required to be dedicated to the electrical installation.
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Very interesting indeed. I missed that discussion.
 
I had the about the same thought Tom did.

How is this any different than a flush mounted panel??

IMO, there is no violation.

P.S. I also read Don's comment too fast. Now I think I see what the point of this thread is about.
 
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