The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!

Featured:
   

2017 NEC and Related
2017 NEC
Now Available!

   
Recent Posts
Industrail Control Panel bonding per 409.108
by sparkyinak
12/09/16 06:29 PM
Calling all Non-US members!! (Non-US only)
by aussie240
12/07/16 02:39 AM
Photo Upload Tutorial
by DanK
12/06/16 11:35 PM
Sprinklered equipment 26-008
by bigpapa
12/02/16 04:24 PM
On Delay Relay with Auto Reset
by Potseal
12/01/16 09:59 AM
New in the Gallery:
12.5A through 0.75mm˛ flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 13
HotLine1 10
sparkyinak 9
Texas_Ranger 8
Trumpy 6
Who's Online
1 registered (brsele), 230 Guests and 4 Spiders online.
Key: Admin, Global Mod, Mod
Topic Options
Rate This Topic
#81202 - 07/21/02 03:25 PM Generator ATS
lousen Offline
Junior Member

Registered: 07/21/01
Posts: 8
Loc: Bryn Mawr, Pa. U.S.A.
One gen. for essential and non-essential loads in nursing home.Does this require two ATS's?-one for each load?

Top
2014 / 2011 NEC & Related Books and Study Guides
#81203 - 07/21/02 03:52 PM Re: Generator ATS
Roger Offline
Member

Registered: 05/18/02
Posts: 1779
Loc: N.C.
Lousen, please read 517.40 and give us a little more information.

517.41(b) 150 kva or less would allow one transfer switch.

There may be some NFPA 99 0r 110 issues to consider.

Roger

Top
#81204 - 07/21/02 04:26 PM Re: Generator ATS
Ron Offline
Member

Registered: 03/13/02
Posts: 577
Loc: White Plains, NY
The fact that it is a nursing home, does this eliminate the Article 700 requirement to keep emergency and non-emergency seperate?
_________________________
Ron

Top
#81205 - 07/21/02 06:06 PM Re: Generator ATS
lousen Offline
Junior Member

Registered: 07/21/01
Posts: 8
Loc: Bryn Mawr, Pa. U.S.A.
Rodger and Ron-These loads are separate but big problem is how to test essential load without shutting down entire building.
Gen.output=300kva.Emergency load =45kva
State requires monthly testing.

Top
#81206 - 07/22/02 09:45 AM Re: Generator ATS
Roger Offline
Member

Registered: 05/18/02
Posts: 1779
Loc: N.C.
Lousen, most of the facilities we maintain or assist in maintaining set a time in the wee hours of the morning.

We do help one hospital that does their tests on Friday afternoon. In the test function of the transfer switch, there should only be a quick blip in the transfer from normal to emergency power and vice versa. This will not be enough to effect normal operation of the facility.

Computers could see some problems if they are not on UPS's

The 45kva load would not meet the 30% as described here http://www.mgi-hcn.com/archive/search/testing/Differences022701.htm

However you might still meet operating temperature. You would need a temperature sensor of some type to be able to record your test. The manufacturer should be able to help you with this.

Hope this is some help.

Roger

Top
#81207 - 07/22/02 12:20 PM Re: Generator ATS
Ron Offline
Member

Registered: 03/13/02
Posts: 577
Loc: White Plains, NY
You should consider a closed transition transfer switch. As long as both sources are operating, the switch waits for the generator to wonder ever so slightly (to be in synch with the utility), then transfers. This leave the testing to be seemless and transparent to everyone outside of the generator or switchgear rooms.
_________________________
Ron

Top



ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals