ECN Forum
Posted By: lousen Generator ATS - 07/21/02 10:25 PM
One gen. for essential and non-essential loads in nursing home.Does this require two ATS's?-one for each load?
Posted By: Roger Re: Generator ATS - 07/21/02 10:52 PM
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
Posted By: Ron Re: Generator ATS - 07/21/02 11:26 PM
The fact that it is a nursing home, does this eliminate the Article 700 requirement to keep emergency and non-emergency seperate?
Posted By: lousen Re: Generator ATS - 07/22/02 01:06 AM
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.
Posted By: Roger Re: Generator ATS - 07/22/02 04:45 PM
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
Posted By: Ron Re: Generator ATS - 07/22/02 07:20 PM
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.
© ECN Electrical Forums