Does 2000A electrical service equipment have to be in its own electrical room

[dahualin]

We designed a 2000A switchboard in mechanical room for a project. Our client believes the 2000A switchboard has to be in an electrical room as required by code. I looked at NEC that doesn't seem to have this requirement. We have designed a lot of big electrical service equipment in machanical room for different projects as long as it has enough working space and dedicated space as required by NEC and the mechanical room is not open to public.

Any comment is welcome. Thanks,

 

[DetroitEE]

If the switchboard is over 6 ft. wide you will need two exits from the mechanical room on opposite sides of the room. There are exceptions to this....however given the fact that the switchboard is located in a mechanical room, I don't think you would be able to meet the requirements. See NEC 2008 110.26(C)(2)

 

[augie47]

As .long as you meet Code requirements, such as 110.26, there is no problem with the gear being in a mechanical room. Many of the industrial, commercial I jobs I see have the service gear in a room which also serves as mechanical.

 

[charlie b]

Our client believes the 2000A switchboard has to be in an electrical room as required by code.

Your client is wrong. They get that way sometimes. :roll: As DetroitEE pointed out, there may be a few special requirements, and they may be difficult to satisfy in a mechanical room. But I would not call it impossible.

 

[DetroitEE]

If the switchboard is over 6 ft. wide you will need two exits from the mechanical room on opposite sides of the room. There are exceptions to this....however given the fact that the switchboard is located in a mechanical room, I don't think you would be able to meet the requirements. See NEC 2008 110.26(C)(2)

I guess I should clarify what I meant by "I don't think you would be able to meet the requirements." I was referring to the requirements of the exceptions which permit you to have only one exit from the mechanical room.

If you're switchboard is 6 ft. wide or less, you're fine. If you're switchboard is over 6 ft. wide but you have two exits from the room, then you're fine there too.

 

[dahualin]

I guess I should clarify what I meant by "I don't think you would be able to meet the requirements." I was referring to the requirements of the exceptions which permit you to have only one exit from the mechanical room.

If you're switchboard is 6 ft. wide or less, you're fine. If you're switchboard is over 6 ft. wide but you have two exits from the room, then you're fine there too.

The NEC 110.26.(C)(2) Large Equipment. For equipment rated 1200A or more and over 6 ft wide that contains overcurrent devices, switching devices, or control devices, there shall be one entrance to and egress from the required working space not less than 24in wide and 6.5 ft high at each end of the working space.

My understanding is if we have 4 ft space in front of the switchboard to meet the working space requirement and at both end of working space we have enough opening to get out of the working space, we meet the 110.26.(c)(2). The opening can be either a door or an open space.

 

[charlie b]

My understanding is if we have 4 ft space in front of the switchboard to meet the working space requirement and at both end of working space we have enough opening to get out of the working space, we meet the 110.26.(c)(2). The opening can be either a door or an open space.

That has been the subject of some entertaining discussions. I was a supporter of that point of view. However, the new 2008 article 110.26(C)(3) takes the wind out of those sails. It speaks of the entrance to the working space being a door 25 feet away. Your point of view, and my previous point of view, would say that once you are (let us say) 10 feet from the closest point in the working space you are done, you are clear, and the existence and locations of doors means nothing. I can't say that anymore.

 

[WastefulMiser]

That has been the subject of some entertaining discussions. I was a supporter of that point of view. However, the new 2008 article 110.26(C)(3) takes the wind out of those sails. It speaks of the entrance to the working space being a door 25 feet away. Your point of view, and my previous point of view, would say that once you are (let us say) 10 feet from the closest point in the working space you are done, you are clear, and the existence and locations of doors means nothing. I can't say that anymore.

NEC 2008 110.26(C)(2)(3):
Personnel Doors. Where equipment rated 1200 A or
more that contains overcurrent devices, switching devices,
or control devices is installed and there is a personnel
door(s) intended for entrance to and egress from the working
space less than 7.6 m (25 ft) from the nearest edge of
the working space, the door(s) shall open in the direction of
egress and be equipped with panic bars, pressure plates, or
other devices that are normally latched but open under
simple pressure.

I wasn't privy to those interesting discussions -- but why can't you say that anymore? To me 110.26(C)(2)(3) just talks about door swing if there are door(s) within 25 feet of the equipment ...

What makes dahualin's statement incorrect? Enlighten me.

 

[charlie b]

The question at hand is this: if you step out of the 30 inch (or the width of the panel) wide deep by 42 inch (or whatever) deep area known as "working clearance," have you achieved what the code wants you to be able to safely achieve, or does the code expect you to be able to leave the room, before you can consider yourself in a safe location? The code words are along the lines of "entrance to and egress from the working space," not "entrance to or egress from the room." But the new code language talks about an "entrance to or egress from the working space" that is located 25 feet away from the working space itself. So I have to infer that just getting away from the equipment is not enough. An exit from the working space can be a door that is nowhere near the working space, and is indeed an exit door out of the room.

 

[dahualin]

I discussed the door requirement with other electrical engineer in our office. Their understanding is that the panic bar requirement at the door is for those electricians who hurt two hands when some accident heppened can still push the panic bar to get out of the room. In that situation, they certainly cannot open doors with knob or handle with their hands.

The code doesn't say the service equpment needs an electrical room or a fire rated electrical room when service equpment is rated 1200A or larger. The code does say the electrical equpment with 112.5KVA transformer or high voltage rating shall have fire rated electrical room or vault.

Does that make sense to you guys?

 

[lakee911]

NEC 708 may apply depending on the type of facility. See 708.5(B).

 

[wonda]

I have this same issue on a project I am working on, where the inspector is saying I have to put the switchgear in a room. I cannot find any thing in the NEC (2008) which even suggest that once I have switchgear with a main breaker of 1200A or more that I have to place it in a room. Currently the switchgear sit near a wall in a factory with the required working space around it.
Here we have to do want ever the Inspector wants but I just can not find where he got this requirement from.

 

[One-eyed Jack]

That has been the subject of some entertaining discussions. I was a supporter of that point of view. However, the new 2008 article 110.26(C)(3) takes the wind out of those sails. It speaks of the entrance to the working space being a door 25 feet away. Your point of view, and my previous point of view, would say that once you are (let us say) 10 feet from the closest point in the working space you are done, you are clear, and the existence and locations of doors means nothing. I can't say that anymore.

I don't quite see it that way Charlie. The less than 25 feet would require panic hardware etc for the door. If it is more than 25 feet the door could swing either way and no panic hardware. Are we done or safe beyond the 25 ft. mark with or without a door??

 

[Mike01]

Rear Access

Rear Access

Does your switchboard requrie "rear access" as I recall the "working space" and associated entrance and egress to the working space apply to both the front and back of the equipment where "rear access" is requried.