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Posted By: drillman Art 700 - 08/27/04 01:08 AM
First a little background. As some of you know I am the facility electrician at a county jail. This facility is composed of 30 buildings.

We had one of our minimum security buildings redone with new AC equipment. This building is an open dorm style with no cells.

There is an emergency generator that powers the egress lighting and the smoke evac system. The smoke evac system is required by the state to be on generator power.

What happen was the contractor was supposed to buy and install two breakers to put in the MDP for two of the AC units. What he did instead was install two breakers in spaces in the emergency panel. I guess they were cheaper than the MDP breakers. So now we got two of 7 ac units being powered from the emergency panel.

I figure thats a violation of 700.9 at the very least. Having a non emergency load in the emergency panel. Anyone here agree with me?

Thanks for any help.
Posted By: gfretwell Re: Art 700 - 08/27/04 03:04 AM
I agree, the A/C is not emergency equipment. Will the generator even carry them with the required loads?
Posted By: iwire Re: Art 700 - 08/27/04 08:17 AM
I also agree this is a violation, regardless of the generators capacity.

Check out 700.6(D)

700.6(D)Use. Transfer equipment shall supply only emergency loads.
Posted By: earlydean Re: Art 700 - 08/27/04 08:13 PM
But, check out 700.5(B). If the generator is large enough or has selective loading, it is allowed to be used to power optional standby system loads.
I don't believe it applies in this specific case, however.
Posted By: iwire Re: Art 700 - 08/27/04 08:37 PM
Yes the generator itself can power other than emergency loads but... the other loads will need seperate feeders, transfer switches panels and branch circuits.

The genertor will need a breaker on it for the emergency loads and a second breaker on it for optional loads.

Quote
700.9 Wiring, Emergency System.

(B) Wiring. Wiring of two or more emergency circuits supplied from the same source shall be permitted in the same raceway, cable, box, or cabinet. Wiring from an emergency source or emergency source distribution overcurrent protection to emergency loads shall be kept entirely independent of all other wiring and equipment, unless otherwise permitted in (1) through (4):

(1)Wiring from the normal power source located in transfer equipment enclosures

(2)Wiring supplied from two sources in exit or emergency luminaires (lighting fixtures)

(3)Wiring from two sources in a common junction box, attached to exit or emergency luminaires (lighting fixtures)

(4)Wiring within a common junction box attached to unit equipment, containing only the branch circuit supplying the unit equipment and the emergency circuit supplied by the unit equipment.
Posted By: Local Re: Art 700 - 08/27/04 11:33 PM
I know this is beside the point. I know a contractor did other then instructed but consider the following:

Who defines "emergency load"?

I might consider AC units to be necessary equipment during a power outage in the summer. Do you know what happens when you have 2500 inmates 42 to a barracks when the power goes out in the heat of the desert summer? I do. You might think they don't deserve it but for the safety of the CO's and the inmates I would consider AC's to be necessary.
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