Distribution to Systems and Branches

[roger]

Does anyone see anything that is not right in the attached drawings? This is in a medical facility

Roger

 

[charlie b]

I presume that the source of the emergency side is either a diesel generator or a separate utility. That part is OK. But the distribution board on the emergency side has to have the two breakers that feed the two emergency branches (critical and life safety) on a separate vertical switchboard sections than the other breakers. Reference 700.9(B)(5).

 

[roger]

Charlie, along with your post above, what is your take on 695.3 and 695.4? (I am looking at the 2011)

Roger

 

[charlie b]

Good question, Roger. Regarding 695.3, I don't think the drawing complies with the rule. The connection that serves the fire pump has to be taken upstream of the main service disconnect, and the drawing has it included in the downstream distribution section. You would be OK with 695.4 if, and only if, the transfer switch is listed in combination with the fire pump controller for the purposes of providing supervision from inadvertent disconnection.

 

[roger]

Good question, Roger. Regarding 695.3, I don't think the drawing complies with the rule. The connection that serves the fire pump has to be taken upstream of the main service disconnect, and the drawing has it included in the downstream distribution section. You would be OK with 695.4 if, and only if, the transfer switch is listed in combination with the fire pump controller for the purposes of providing supervision from inadvertent disconnection.

Thanks for the feed back Charlie.

Now, what about

695.4(B)(3)(b)

Features and Locations-On Site Stand-By Generator. The disconnecting means for an on-site stand-by generator(s) used as the alternate power source shall be installed in acordance with 700.10(B)(5) for emergency circuits and shall be lockable in the closed position.

700.10(B)(5)(a)

Wiring from an emergency source to supply any combination of emergency, legally required, or optional loads in accordance with (a), (b), (c), and (d)

(a) From seperate verticle switchboard sections, with or with out a common bus, or from individual disconnects mounted in separate enclosures.

Roger