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Posted By: Jim M Trough under panels? - 01/26/02 04:18 AM
If a 8x8 trough is mounted under a panel or disconnect that is less than 8" deep is this a violation? Code Ref?

Thanks.
Posted By: George Corron Re: Trough under panels? - 01/26/02 04:31 AM
1999 NEC 374-1 Auxiliary gutters shall be allowed to supplement equipment - as long as they don't extend more than 30' beyond the equipment they supplement.
I would ask the one who claims it's illegal for the code reference.
Posted By: resqcapt19 Re: Trough under panels? - 01/26/02 12:33 PM
Jim,
If you are working under a very strict reading of the '96 code that would be a violation. Look at 110-16(a). It said: "...Equipment of equal depth shall be permitted within the height requirements of this section". In areas with very strict enforcement, contractors were required to build racks to make the fronts of the equipment flush with each other if they were within the work space."
This was never the real intent of the code section and it was revised in the '99 code. In the 99 code look at 110-26(a)(3).
"...Within the height requirements of this section, other equipment associated with the electrical installation located above or below the electrical equipment shall be permitted to extend not more than 6 in. (153 mm) beyond the front of the electrical equipment." So as long as it is electrical equipment and there is 6" or less difference in depth, it is ok with the NEC.
Don(resqcapt19)

[This message has been edited by resqcapt19 (edited 01-26-2002).]
Posted By: Joe Tedesco Re: Trough under panels? - 01/26/02 12:49 PM
And in the 2002 NEC, just to be sure see the same rule. 110.26(A)(3) Height of Working Space. The work space shall be clear and extend from the grade, floor, or platform to the height required by 110.26(E). Within the height requirements of this section, other equipment that is associated with the electrical installation and is located above or below the electrical equipment shall be permitted to extend not more than 150 mm (6 in.) beyond the front of the electrical equipment.

Example: No Violation Here!

[Linked Image]

[This message has been edited by Joe Tedesco (edited 01-26-2002).]
Posted By: Jim M Re: Trough under panels? - 01/26/02 05:12 PM
Thanks for the replies. This will be an outside installation. I need to set 2 disconnects off of one meter. One d/c feeds a MLO panel in bldg 'a', the other feeds bldg 'b'. The area is still under the '93 Code.
Posted By: golf junkie Re: Trough under panels? - 01/27/02 04:57 PM
The AHJ for Nebraska says that this is a violation. Don't remember the specific code reference off the top of my head.

Bottom line is that we shim the panelboard out to be flush with the gutter.

GJ

***After rereading Don's post I'm going to have to ask the inspector about this the next time I run into him. Seems that perhaps the rules have changed.

thanks Don!

[This message has been edited by golf junkie (edited 01-27-2002).]
Posted By: George Corron Re: Trough under panels? - 01/28/02 04:20 AM
Guys,
Agreed on all the references. I was taught long ago, and have always enforced this way, that when you used auxiliary gutter, which is Code allowed to SUPPLEMENT service equipment, that it became part of the equipment, not merely 'other' equipment, such as time clocks, contactors, etc..
Have I been to lax on this? [Linked Image]
Posted By: resqcapt19 Re: Trough under panels? - 01/28/02 01:47 PM
Jim,
The '93 code language is not clear on this. It can be read as requiring the equipment to be flush with each other. I don't have my ROP here, but I think that part of the substantiation for the '96 wording was to make it clear that even other electrical equipment couldn't be in the "work space". After the '96 code came out, everyone found out that the flush requirement was unworkable and is was changed to 6" for the '99 code.
Don(resqcapt19)
Posted By: Elzappr Re: Trough under panels? - 01/28/02 06:38 PM
So let me get this straight, George. If a gutter was considered part of the equipment, eg., service equipment, then you have been allowing the gutter to be extended out past the front of the panel?, in apparent violation of the old code?
I can see the value of treating the gutter as part of the service equipment, as far as clearances and bonding requirements are concerned, tho I don't know where to find such stipulation in the code. My working "assumption" was that the "flush" requirement was to eliminate the shock hazard and stumbling hazard associated with protruding grounded stuff..so that you could work on the equipment (requiring service or adjustment) without having to duck under,lean on, or touch any grounded surfaces.
The newer codes allow 6", which is reasonable enough in practice. Its not usual for someone to be sticking his/her 'nose' right into the gear while working on it. Assumption being that we don't need more than 6" [Linked Image]
Posted By: The Watt Doctor Re: Trough under panels? - 01/29/02 12:50 AM
Nice photography Joe. IMHO the rule is there to prevent installations like the one I ran into not long ago. In an electrical closet with limited space, some electrician, set a 480/208-120/3ph transformer directly in front of the panel it was feeding. I do have to hand it to him....at least he spaced the transformer off the wall about 4". Do you think that he knew 450-9? [Linked Image]
Posted By: frodo Re: Trough under panels? - 01/29/02 10:16 PM
hi,
i beleive the gutter or ANY other equipment may extend a maximum of SIX INCHES out from the front plane of the panel above it...

i dont have my book here but i read it the other day in stallcups electrical design book...1999 version

-regards

frodo
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