Panel height, min max?

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Dennis Alwon

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Chapel Hill, NC
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There is no minimum unless it is a mobile home. I believe the mobile homes have a minimum of 2' to the bottom of the panel. 550.11(A)

The max height has to do with breakers. 240.24(A) calls for 6'7" as max.
 

Jraef

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There is a requirement for the maximum height of an operating handle from the floor, I think it is 7'6", but I could be wrong. It's so that an average height person does not have to use a stool or ladder to reach it, defined as something like a 5'6" person with a 2' reach. I know where I can access that info, I just don't have it here. I'll check and post later. Also if there is a chance of flooding it's a good idea to keep electrical equipment off the floor, but I don't think that has a regulation associated with it, just good common sense.
 

Little Bill

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Tennessee NEC:2017
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There is a requirement for the maximum height of an operating handle from the floor, I think it is 7'6", but I could be wrong. It's so that an average height person does not have to use a stool or ladder to reach it, defined as something like a 5'6" person with a 2' reach. I know where I can access that info, I just don't have it here. I'll check and post later. Also if there is a chance of flooding it's a good idea to keep electrical equipment off the floor, but I don't think that has a regulation associated with it, just good common sense.

A little dyslexia here....6'7"
 

PEDRO ESCOVILLA

Senior Member
Location
south texas
mobile homes are'nt regulated by nec, but by hud requirements. maximum height of switches (breakers, etc) is 6 feet 7 inches, per 404.8 nec, 2008. not aware of a "minimum height off the floor, however, as previously posted, rain, flooding come into play, and accessability, i prefer to work on my feet, and being tall, standing is preferable to kneeling, especially on things like panelboards, however, if the situation requires otherwise, one must adapt
 

PEDRO ESCOVILLA

Senior Member
Location
south texas
for set up, but it does not cover the interior wiring of a mobile home. check the scope 550.1, have you ever done a mobile home "rough in' inspection ? there are places that built modulars that get inspected, but thats a different deal, that like a prepaneled house in sections. i was also wrong in that they are not "regulated here " other than set up. my apologies. it's good to be wrong sometimes.
 

kwired

Electron manager
Location
NE Nebraska
A little dyslexia here....6'7"

It used to be 6'6". I think it was either 2002 or 2005 when it changed to 6'7". I think the change was mostly because 6'7" is also 2.0 meters (or very darn close).


And yes, the height is to center of operating mechanism of the highest device in the panel. The cabinet itself could be much higher and often is on higher amperage equipment just so there is room for wire bending within the cabinet.
 
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kwired

Electron manager
Location
NE Nebraska
600 amp I-Line panel on other side of wall where I am at right now. Top of cabinet is about 9 feet above floor. Highest breaker handle is under 6-7. A lot of space above 6-7 is necessary because neutral bus is there. If the neutal bus would have been on bottom, the highest breakers would be too high.
 

maghazadeh

Senior Member
Location
Campbell CA
It used to be 6'6". I think it was either 2002 or 2005 when it changed to 6'7". I think the change was mostly because 6'7" is also 2.0 meters (or very darn close).


And yes, the height is to center of operating mechanism of the highest device in the panel. The cabinet itself could be much higher and often is on higher amperage equipment just so there is room for wire bending within the cabinet.

I agree with Kwired in respect to max. height, but regarding min. height the only thing I recall is in the flood zone all device boxes most be min. 18" off the floor and I belive that would be for panels too.
 

kwired

Electron manager
Location
NE Nebraska
I agree with Kwired in respect to max. height, but regarding min. height the only thing I recall is in the flood zone all device boxes most be min. 18" off the floor and I belive that would be for panels too.

There is no minimum, a lot of large gear is open bottom and designed to sit on the floor.

As far as an area subject to flooding - that is entirely different topic. We had flooding along Missouri river this past summer and many places you were not going to mount it high enough - period. But that was something you just don't plan for.

In places that routinely are subject to water an enclosure designed for the environment is a must or locate it in a dry location.
 

hurk27

Senior Member
mobile homes are'nt regulated by nec, but by hud requirements. maximum height of switches (breakers, etc) is 6 feet 7 inches, per 404.8 nec, 2008. not aware of a "minimum height off the floor, however, as previously posted, rain, flooding come into play, and accessability, i prefer to work on my feet, and being tall, standing is preferable to kneeling, especially on things like panelboards, however, if the situation requires otherwise, one must adapt

Both the NEC 550.11(A):
The distribution equipment, either circuit
breaker or fused type, shall be located a minimum of
600 mm (24 in.) from the bottom of such equipment to the
floor level of the mobile home.


And CFR 24 3280.804(d) require a minimum of 24" off the floor:

(d) The distribution equipment, either circuit breaker or fused type, shall be located a minimum of 24 inches from the bottom of such equipment to the floor level of the manufactured home.

Just about word for word.
 

Jraef

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Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
It used to be 6'6". I think it was either 2002 or 2005 when it changed to 6'7". I think the change was mostly because 6'7" is also 2.0 meters (or very darn close).


And yes, the height is to center of operating mechanism of the highest device in the panel. The cabinet itself could be much higher and often is on higher amperage equipment just so there is room for wire bending within the cabinet.

20 years ago I worked for a mfr who's MCCs were designed such that the top most handle ended up 1/2" too high in the On position. So we had to ship every one with a "free" thick rubber mat to go in front of it. We were told to sell it as a safety feature. Looks like they would have eventually prevailed had they survived.
 

kwired

Electron manager
Location
NE Nebraska
20 years ago I worked for a mfr who's MCCs were designed such that the top most handle ended up 1/2" too high in the On position. So we had to ship every one with a "free" thick rubber mat to go in front of it. We were told to sell it as a safety feature. Looks like they would have eventually prevailed had they survived.

Now that they raised min height a couple code cycles ago by 1" they are compliant. Maybe they didn't make a mistake, just the CMP for that section did:happyyes:
 

gndrod

Senior Member
Location
Ca and Wa
Its a gas

Its a gas

I agree with Kwired in respect to max. height, but regarding min. height the only thing I recall is in the flood zone all device boxes most be min. 18" off the floor and I belive that would be for panels too.

Good point. Additionally, panel equipment installations and device boxes are required to be 18" above the garage floor to avoid vapor ignition. UPC 1310(a), IRC M1307.3 vapor
 

kwired

Electron manager
Location
NE Nebraska
Good point. Additionally, panel equipment installations and device boxes are required to be 18" above the garage floor to avoid vapor ignition. UPC 1310(a), IRC M1307.3 vapor

They are not required to be above 18".

They are required to comply with Art 500-517 if they are below 18" and the area below 18" is classified.
 

kwired

Electron manager
Location
NE Nebraska
500-517 is not very specific. What section are you reading?

No single one in particular.


If the area is not classified then none of those sections apply.

There are sections that do classify the area up to 18" above floor, in those places you could still have a panelboard within 18 inches of the floor, but the panelboard would have to be rated for the classified area making it much more expensive than using a so called general purpose panelboard and keeping it out of the classified area.
 
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