# What to do with 347v



## Toronto Sparky (Apr 12, 2009)

guitarboyled said:


> My next questions concerns 347/600v. I understand why we would need 3 phase 600v on large equipment. But what can we do with 347v single phase? Is it actually used or do users bring it down to 120v with a transformer?


347v is used in lighting (I think mostly in Canada) 347v sure bites ya when ya touch it. 

Most of the Bigger Buildings in Toronto are wired with 347v lighting.. (Even the exit lights)


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## guitarboyled (Jun 22, 2009)

Before asking the stupid question of the day which was: I presume specific fluorescent lights and bulbs are required for 347v lighting. I checked out a Fluorescent light retailer.

http://www.saverpluslighting.com/bulbs/fluorescent-ballasts.php

I noticed they have some for 120v, 277v, 240v, 347v and even 600v (3 phase???)

I also presume such a building somehow would have a parallel 120v single phase at least for receptacles?


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## RePhase277 (Feb 5, 2008)

guitarboyled said:


> Before asking the stupid question of the day which was: I presume specific fluorescent lights and bulbs are required for 347v lighting. I checked out a Fluorescent light retailer.
> 
> http://www.saverpluslighting.com/bulbs/fluorescent-ballasts.php
> 
> ...


Just like the 120/208 V wye connected system, the 347/600 V system has 347 V to neutral, and 600 V between any two phases. Usually, 600 V 3-phase is brought to a transformer, where it is stepped down to 120/208 V 3-phase. The 120 V is used for general power, and 347 V is used for lighting, while the 600 V is used for big equipment like A/C. Some parking lot lighting uses 600 V single phase by utilizing just two of the 600 V lines.

P.S.: This is not a native voltage in the U.S. As far as I know, no power utility provides 347/600. I have seen 600 V derived in a factory by a transformer for a specific piece of equipment, but usually industrial supply voltage is 277/480 in the U.S.


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## user4818 (Jan 15, 2009)

600 volt delta systems used to be common in the US (well, around here anyway, and I would guess elsewhere.) I've run into a few but they are very old and have been in operation for decades.


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