Smoke Curtains - EM, normal or stand-by power

[cdcengineer]

I am working on a job and the contractor says they always install the 120V circuiting for elevator door smoke curtains to the EM power. I looked at the mfg's literature and it says that it can be installed to stand-by power.

I do not see this being considered EM. But would agree that it could be optional stand-by. However, on the (2) egress elevators that operate on EM power I would say that in this instance the smoke curtains should be on an EM circuit so that the doors will be accessible once the building transfers to the generator.

Any feedback is greatly appreciated.

 

[JoeStillman]

Are the elevators part of the architect's egress plan, or are they on emergency just for convenience? It makes a difference.

 

[cdcengineer]

The (2) elevators are part of egress. Therefore the gen-set = EM not stand-by or optional stand-by

 

[JoeStillman]

I would put the smoke curtains on Emergency.

 

[cdcengineer]

All smoke curtains, or just the ones associated with the (2) egress elevators? I have a total of (7) elevators and it's my opinion that the other (5) non-EM elevators cannot be on the EM power.

Thx

 

[Strathead]

I am working on a job and the contractor says they always install the 120V circuiting for elevator door smoke curtains to the EM power. I looked at the mfg's literature and it says that it can be installed to stand-by power.

I do not see this being considered EM. But would agree that it could be optional stand-by. However, on the (2) egress elevators that operate on EM power I would say that in this instance the smoke curtains should be on an EM circuit so that the doors will be accessible once the building transfers to the generator.

Any feedback is greatly appreciated.

This could end up as another splitting hairs discussion. For the sake of correctness, just because a circuit or a panel is fed from a generator doesn't make it an "EM" panel in the NEC sense of "legally required emergency system" So, that said, common sense would dictate that a smoke curtain should be on a power source that allows access to the elevator whenever the designer has dictated that the elevator is powered. So, if the designer has provided back up power for the elevator, then back up power should also be provided for the smoke curtain, otherwise don't bother to provide elevator power.

 

[cdcengineer]

If the panel fed from the generator happens to be the only leg of generator power (ie no separate panels, or swbd sections) than it is considered EM power. I would absolutely agree that the (2) EM elevators have their associated smoke curtains connected to EM power, but I would say that the other elevators cannot have the smoke curtains connected to the EM system.