Do you guys apply artical 110. 7.2.2

[dahualin]

NFPA 110 Emergency and standby power systems article 7.2.2 mentioned "Level 1 EPSS equipment shall not be installed in the same room with the normal service equipment, where the service equipment is rated over 150volts to ground and equal to or greater than 1000 amperes". That means all emergency equipment such as ATS, emergency panel boards shall not be located in electrical room if the normal service is equal to or greater than 1000A. Do you guys apply this code for your projects? Thanks.

 

[rcwilson]

For emergency systems -(Level 1) yes. For optional standby systems that do not operate a fire pump, exit lights or any life safety equipment -no. (Systems not classified as even Level 2).

We take care in identifying the system as a backup generator or a standby generator and never refer to it as an emergency unit, to avoid the mistaken impression that the plant design relies on the generator for safety in a power outage.

The insurance inspectors seem to have the biggest problem grasping the difference. A client's letter or permit application mentioning the EDG (Emergency Diesel Generator) has been enough to force us to add a CMU wall and rewire the system.

 

[charlie b]

I recently completed a design in which the large, main electrical room had a smaller, "emergency equipment room" built within it. There is a fire rated wall and door that separates the smaller room. Inside the smaller room, there are two ATS's and two distribution boards (Emergency and Optional Standby).

 

[dahualin]

Does the ATS generate a lot of heat? I know panelboard doesn't generate heat. Does the small emergency equipment room need an exhaust fan?

 

[charlie b]

We used a value of 400 watts as the amount of heat generated by each ATS, and 300 watts as the amount of heat generated by each distribution board. This room has two of each, so the mechanical engineers used 1400 watts as the total heat load that their ventilation system was required to remove. They drew air out of the room with a connection to the main electrical room's exhaust ducting, and put a rectangular opening in the adjacent wall to allow air to enter the room. Both penetrations had fire/smoke dampers.

 

[MIEngineer]

Would this separation still apply if the same generator supplies the emergency (exit signs, egress lighting) and the optional (all other building systems) loads in the building?

 

[charlie b]

The requirement comes from NFPA 110, paragraph 7.2.2:

EPSS equipment shall not be installed in the same room where normal electrical service equipment is installed.

In an earlier paragraph, it defines EPSS, ?Emergency Power Supply System,? as essentially the emergency branch of the distribution system, including conductors, disconnecting means and overcurrent devices, transfer switches, and some other stuff.

So if the same generator supplies emergency and optional standby loads, or if it only supplies emergency loads, the requirement is the same.