Space above a panelboard

[Texhunter7]

Is there a minimum height above a panel for working room or can a transformer hang just above the panel?

 

[chris kennedy]

Is there a minimum height above a panel for working room or can a transformer hang just above the panel?

Heres the quick answer. More to come.:smile:

110.26(E) Headroom. The minimum headroom of working spaces about service equipment, switchboards, panelboards, or motor control centers shall be 2.0 m (6? ft). Where the electrical equipment exceeds 2.0 m (6? ft) in height, the minimum headroom shall not be less than the height of the equipment.
Exception: In existing dwelling units, service equipment or panelboards that do not exceed 200 amperes shall be permitted in spaces where the headroom is less than 2.0 m (6? ft).

 

[Texhunter7]

Just what i thought the job we are doing they hung the transformer 8-12" above the 277/480 volt panel, and i thought that i was correct just wanted to check.

 

[tom baker]

But in the working space equipment must be of equal depth.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.

As long as your transformer does not extend 6" past the front of the panel you are OK.

 

[iwire]

IMO the transfomer can be over the working space.

If it is over the panel then you run itnto the rule Tom pointed out electrical equipment shall be permitted to extend not more than 150 mm (6 in.) beyond the front of the electrical equipment.

 

[Texhunter7]

It is well over 6" extending out in front of the panel, it is around 1 1/2 - 2" out in front of the panel. I could not remember the code of having this situation of headroom above a panel but thanks to ya,ll.

 

[charlie b]

I agree with Bob, and it is a point often confused by many. The space above the panel itself has a different rule than the working space in front of the panel. If you can stand in front of the panel, and have 78 inches of space from the floor to whatever is above your head, then there are no restrictions whatsoever about what is allowed to be above your head. There can be a transformer over the panel, and it can extend as far from the wall as you like, so long as you can stand under it, with 78 inches clear from the floor to its bottom support.

Above the panel itself, however, you cannot have anything "foreign" to the electrical installation for a distance of 6 feet above the top of the panel. You can have foreign things, such as a pipe or an HVAC duct, installed more than six feet above the top of the panel, but only if there is a drip shield in place. But a transformer is not "foreign" to the panel, so a transformer can be directly over the panel. Again, if it extends further than the front face of the panel, then see the paragraph above for the clearance rules.