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#130772 - 12/30/06 07:52 AM 277 to 120 transformer
village-electric Offline
Junior Member

Registered: 10/16/06
Posts: 4
Loc: Sedona, AZ
Hi,

I have a customer in a medical center office wanting to light up some art work.

We spoke of a 4' track and 4-5 heads.
Anyone have a source for transformer for this application?

Thanks Steve

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#130773 - 12/30/06 09:59 AM Re: 277 to 120 transformer
iwire Offline
Moderator

Registered: 01/05/03
Posts: 4343
Loc: North Attleboro, MA USA
Assuming one 20 amp circuit I would use a 3.O KVA 277 to 120 transformer.

This should be a shelf item at a major supply house.

Square D, GE, Jefferson and many others make them.

Than you need to go to 250.30 for grounding this transformer and Article 450 for overcurrent protection of it.
_________________________
Bob Badger
Construction & Maintenance Electrician
Massachusetts

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#130774 - 12/30/06 10:04 AM Re: 277 to 120 transformer
iwire Offline
Moderator

Registered: 01/05/03
Posts: 4343
Loc: North Attleboro, MA USA
By the way, I assume it must be really difficult to run a new 120 volt circuit to this location?

In my opinion doing a 'legal' transformer install for this will cost quite a bit.

I would tap a receptacle circuit to run this one track.
_________________________
Bob Badger
Construction & Maintenance Electrician
Massachusetts

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#130775 - 01/21/07 01:22 PM Re: 277 to 120 transformer
Tesla Offline
Member

Registered: 06/16/04
Posts: 1280
Loc: Sacramento, CA
Consider Low Voltage spot lamps.

Order 277 to 12VAC transformers -- as against the typical 120 to 12VAC transformers.

These are listed equipment that you'd place at each 4' section.

The last ones I touched were on pendant rails.

Not cheap to buy or install. But very classy. And that's the whole point of the display, anyway.
_________________________
Tesla

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