UPS used for Legally required standby

[mshields]

I'm looking at an application where the client wants to put in a pair of 1MW generators operating in parallel to provide an alternative power source to 7 dormitories. So there will be one feeder into the building such that the generator source is like having a second utility source.

We're going to deal with Article 700 requirements with EBU's

But we have this odd load comprised of multiple fractional horse power fans that actually serve as smoke exhaust. So ordinarily I'd put in a local generator with a Legally Required Standby ATS, (I'd no doubt put the emergency lights on an Article 700 ATS) and off we'd go.

Given that the facility is already backed up by a generator albeit one that can't fulfill requirements of Article 701, we're considering putting this load on a UPS. Article 701.

Article 701 does list storage batteries (I believe a UPS qualifies does it not) as a legitimate source. So I guess it would be compliant. Still it's not something I've seen done and I'm uneasy about it.

I guess there would be no ATS since we'd be using an on line double conversion type UPS. Well, for that matter even a line interactive type would work. But we're still not looking at a conventional ATS. Is that ok?

Lastly, I assume we'd need for the UPS to be UL 924 correct?

 

[gadfly56]

I'm looking at an application where the client wants to put in a pair of 1MW generators operating in parallel to provide an alternative power source to 7 dormitories. So there will be one feeder into the building such that the generator source is like having a second utility source.

We're going to deal with Article 700 requirements with EBU's

But we have this odd load comprised of multiple fractional horse power fans that actually serve as smoke exhaust. So ordinarily I'd put in a local generator with a Legally Required Standby ATS, (I'd no doubt put the emergency lights on an Article 700 ATS) and off we'd go.

Given that the facility is already backed up by a generator albeit one that can't fulfill requirements of Article 701, we're considering putting this load on a UPS. Article 701.

Article 701 does list storage batteries (I believe a UPS qualifies does it not) as a legitimate source. So I guess it would be compliant. Still it's not something I've seen done and I'm uneasy about it.

I guess there would be no ATS since we'd be using an on line double conversion type UPS. Well, for that matter even a line interactive type would work. But we're still not looking at a conventional ATS. Is that ok?

Lastly, I assume we'd need for the UPS to be UL 924 correct?

Is that for smoke control or smoke purge? Smoke control is a life safety system, smoke purge is not.

 

[mshields]

purge vs control

purge vs control

what's the diff?

 

[gadfly56]

what's the diff?

The intent of smoke control is to maintain a tenable environment along the path of egress so occupants can safely exit the building. Smoke purge is engaged to clear the building of any lingering smoke after the first responders declare the fire is kaput and it's OK to resume normal operations. The first is life-safety, the second is not.

 

[mshields]

ah - thank you!

ah - thank you!

Then THIS application is smoke control

 

[ron]

UL 924 spec is the way to go. It will be a 90 minute battery and off you go.