Dedicated equipment space for subpanel?

WoodworkerDave · 09-13-2008, 12:19 PM

I've read in NEC 2008 part 110-26(f)(1)(a) that "panelboards .... located indoors must have an exclusive dedicated space (from the floor upward to 6 feet above the equipment) the width and depth (footprint) of the equipment." This means no pipes, ducts, etc. intruding into this "space", although suspended ceilings are ok.

I had planned on putting a subpanel adjacent to my existing service panelboard to accommodate additional circuits in my shop. Am I correct in assuming that my subpanel must also conform to the exclusive dedicated space rule? My original location planned for the subpanel has a heating duct running in the joist space above it. I will likely have to install the subpanel further away from the existing service panelboard so as to meet the exclusive dedicated space rule.

Also, I previously had free online access to the NEC. This no longer seems to be the case. Is there still a free site?

Thanks for your help.
Dave

**Termite** · 09-13-2008, 01:58 PM

You're correct in your understanding that panelboards require a dedicated space of 30" width and 36" depth in front of them. The working space measurement is taken off of the face of the panelboard, not the back. Therefore, I don't think that installation of a sub-panel next to another panel is in violation of the code. The working space isn't even required to be centered on the panelboard. The panelboard can be on one side of the working space or the other.

Here's a crude drawing showing three legal installations...

chris75 · 09-13-2008, 02:04 PM

Quote:

Originally Posted by WoodworkerDave

My original location planned for the subpanel has a heating duct running in the joist space above it. I will likely have to install the subpanel further away from the existing service panelboard so as to meet the exclusive dedicated space rule.

This code rule is for 6' or the structural ceiling, IMO, if the duct work is inbetween the joist, then your fine.

**Termite** · 09-13-2008, 02:06 PM

Here's a couple code violation of the working space requirements...

**Termite** · 09-13-2008, 02:09 PM

Quote:

Originally Posted by chris75

This code rule is for 6' or the structural ceiling, IMO, if the duct work is inbetween the joist, then your fine.

That can be an interpretive issue though. "Structural ceiling" is not defined. I worked in a city that considered the structural ceiling as the underside of the floor sheathing if the space was not finished. Not that I agree with that stance....

The best-case installation involves not having anything besides framing or wiring above the panel.

chris75 · 09-14-2008, 09:42 AM

Also wanted to point out that this goes for UNDER the panel as well.
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SD515 · 09-14-2008, 04:41 PM

Good points Chris & KC.

I don't have the '08 code avail to me today...just the '05...Is 110.26(F)(1)(b) Foreign Systems, still in the '08 ??

chris75 · 09-14-2008, 04:43 PM

Quote:

Originally Posted by SD515

Good points Chris & KC.

I don't have the '08 code avail to me today...just the '05...Is 110.26(F)(1)(b) Foreign Systems, still in the '08 ??

I dont have one either, but I can pretty much guarantee that it is.

SD515 · 09-14-2008, 04:54 PM

I thought so too, but wasn't sure. If that's the case the OP should be okay with his proposed idea, as (b) says foreign systems are okay as long as protection is installed to prevent damage....

theatretch85 · 09-14-2008, 04:59 PM

I just checked my 2008 NEC code book and yes that section is in the code book. It basically indicates that there can be foreign systems directly above the 6ft zone provided "protection is installed to avoid damage to the electrical equipment from condensation, leaks or breaks in such foreign systems."

I would interpret that to mean ventilation, water pipes, etc so long as they are higher than 6ft, and have adequate protection around them to avoid damage to the panel (ex: foam pipe wrap).

chris75 · 09-14-2008, 06:35 PM

Quote:

Originally Posted by theatretch85

I just checked my 2008 NEC code book and yes that section is in the code book. It basically indicates that there can be foreign systems directly above the 6ft zone provided "protection is installed to avoid damage to the electrical equipment from condensation, leaks or breaks in such foreign systems."

I would interpret that to mean ventilation, water pipes, etc so long as they are higher than 6ft, and have adequate protection around them to avoid damage to the panel (ex: foam pipe wrap).

To me that would mean some type of drip pan be installed over the panels.

SD515 · 09-14-2008, 07:32 PM

Pretty much..or some kind of guard...depends what the 'foreign system' is. A Mike Holt text book I have shows a drip pan in it's illustration...I'll check to see if I can find a web photo.

Also, my bad to my previous post. I missed the word 'dedicated' as in 'The area above the dedicated space'... I kept thinking I was missing something.