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#101889 - 01/05/04 03:21 PM 347 lighting
Clyde Offline
Member

Registered: 10/17/03
Posts: 31
Loc: Leamington
I have a qustion someone might be able to help me with. A farmer asked me today if he could install 60 347 volt lights. He does not have a neutral on his primary service going into his building. Can this be accomplished without the use of transformer to provide a neutral to install these lights.....

Thanks

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#101890 - 01/06/04 08:55 PM Re: 347 lighting
crash Offline
Member

Registered: 10/21/03
Posts: 130
Loc: Calgary Canada
Clyde: When you mention service neutral, are you talking about a service or are you talking about a feeder. A service has to have a neutral, see 4-022 (3). If it is a 600V feeder, 347V can (in theory) be obtained by a wye connection, but this is not acceptable to code. The star point is a neutral and has to be grounded at the service, 10-106 (1),(b) and 10-204 (1),(a).

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#101891 - 01/07/04 11:34 AM Re: 347 lighting
GETELECTRIC Offline
Member

Registered: 10/22/03
Posts: 178
Loc: toronto canada
why not just go 600v lighting?

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#101892 - 01/07/04 06:46 PM Re: 347 lighting
Clyde Offline
Member

Registered: 10/17/03
Posts: 31
Loc: Leamington
The problem is this farmer is pretty cheap. He was given the 347 volt light fixtures and is not really interested in spending any money.
The service is quite old and is only a three wire, 600 volt. 400 amp.
I did a little research and the only thing I can find is that he needs a transformer at least 25kva.
Something about doing mostly control work, you don't get a whole lot of experience with this sort of thing.
Thanks for your help.

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#101893 - 01/07/04 09:10 PM Re: 347 lighting
Bjarney Offline
Moderator

Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
If Canadian Codes permit and the building service is ungrounded 600V 3-wire, it may be possible to assemble a zig-zag grounding autotransformer to provide a neutral for the 347V fixtures. Three drytype transformers rated 240 x 480 Volts–120/240 Volts would be OK for up to 360V ø-n. [Alternate rating 120 x 240 Volts – 120/240 Volts]

The arrangement for operating 277V lighting on a 480V ungrounded service is described in: www.ecmweb.com/ar/electric_unconventional_transformer_connections In this case, three 1½KVA transfomers permitted 18.75A/ø.

Clyde — What is the namplate current on the sixty 347V fixtures?

[If you like, I can post a typical interconnection diagram when the local server is back up.]

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#101894 - 01/08/04 02:57 AM Re: 347 lighting
Clyde Offline
Member

Registered: 10/17/03
Posts: 31
Loc: Leamington
The name plate currant is 1.2 amps.

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#101895 - 01/08/04 06:57 AM Re: 347 lighting
GETELECTRIC Offline
Member

Registered: 10/22/03
Posts: 178
Loc: toronto canada
just curious but if you open up the cover to these fixtures they might be a multi tap ballast,or you might want to ask manufacturer if they can be changed to 6oov,easily.

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#101896 - 01/12/04 12:36 PM Re: 347 lighting
Bjarney Offline
Moderator

Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
 

 

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#101897 - 01/12/04 12:54 PM Re: 347 lighting
Bjarney Offline
Moderator

Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
Looks like 24 amperes/ø. So, that would translate to a set of 2kVA 240x480–120/240V drytypes, or 120x240—120/240V units, with appropriate connection changes in the diagram.

Note that in NFPA territory, the arrangement is permitted by 99NEC450-5, with attention paid to the overcurrent-device location in the circuit.

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#101898 - 01/12/04 10:35 PM Re: 347 lighting
u2slow Offline
Member

Registered: 09/18/03
Posts: 198
Loc: Salt Spring, BC, Canada
Maybe its worth inquiring to see if the power authority can upgrade the service to include a neutral?

(I haven't a clue what the transformer solution is worth.)

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