Breaker size for pressurization & smoke fans

[m sleem]

For a hospital project, i would think those fans will be supplied by the life safety branch. What code says bout the breaker size?
& if we calculate the breaker size as per LRA, do you think it is a sensible approach?

 

[chris kennedy]

For a hospital project, i would think those fans will be supplied by the life safety branch.

Don't think you can put those on LS. 517.32 and 42.

 

[jumper]

517 and LS aside, I thought that just about the only motor OCPDs sized to LRA were fire pumps.

 

[m sleem]

Oooh, that was my mistake, I found in equipment branch delayed automatic connection517.34(a)(4).

Mmmmmmm, i think we need to take a look again at 517.32(c)(3) & 517.34(a)(4). Have you seen this confusion?!!

 

[m sleem]

I agree with you, But don't you think we need to ensure that those fans will continue working during the fire case?

 

[jumper]

I agree with you, But don't you think we need to ensure that those fans will continue working during the fire case?

Who are you agreeing with?

 

[m sleem]

Who are you agreeing with?

You..

 

[iwire]

I agree with you, But don't you think we need to ensure that those fans will continue working during the fire case?

I don't believe the NEC allows us to treat the fans like a fire pump.

 

[jumper]

I don't believe the NEC allows us to treat the fans like a fire pump.

I cannot think of any motor that the NEC treats like fire pumps.

There may be one, but I have not run across it.