# dividers



## RePhase277 (Feb 5, 2008)

Ejw said:


> I understand you need them to seperate 2sw or 2rec if voltage exceeds 300v does this also apply in a jbox if you splice a set of 277v lighting circuits and 120v rec circuit in same splice box insulation rating on both are the same


Not for a splice. It only applies to devices. With different voltage systems you still need to identify the neutrals of each. For example, gray for 277 and white for 120. I try to keep them as separate as is practical, not putting 277 and 120 in the same box, if I can avoid it.


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## mollydog (Jan 9, 2009)

Yes they can with some conditions: 1) 200.6 (D) Grounded conductors of different systems, also ungrounded conductors of dissimiliar voltages shall be identified as such, i.e 120V to ground Black, white, green & 277 to ground Orange, brown, yellow with a grounded conductor (neutral) of a different color other than white, I think natural grey or white with 3 grey stripes. I'm not looking at a 2005 or 2008 I left them on my desk @ work and I'm off today, so I'm getting part of this from my head and part from 2002 code that I have here at home. It's not the intent of the code to require normal servicing such as switches, in a "junction box" If I were the inspector I would also require the junction box be identified " Warning 120 & 277 volt branch circuits contained in this junction box" The only other mandate is that the insulation of the lower voltage to ground be identical to the insulation with the higher voltage to ground to safely limit any potential imposed by mistake. Also check out article 210 ( read all of it) Like I said I only have a 2002 at home. I hope this helps...:yes:


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## RePhase277 (Feb 5, 2008)

mollydog said:


> If I were the inspector I would also require the junction box be identified " Warning 120 & 277 volt branch circuits contained in this junction box"


If you were the inspector and required that, you'd better have it on file as an amendment to the Code, otherwise, you got no footing.


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## micromind (Aug 11, 2007)

If the transformer feeding the 120 volt loads is a 3 phase 480 delta to 120/208 wye, the 30 degree phase shift will cause one of the 277 and 120 volt combinations to yield less than 300 volts between them. 

I've yet to try this on an actual job, because the inspectors around here don't enforce the divider rule. 

It'd be interesting to get busted on this, then hot both circuits up, and show the inspector an actual voltage reading of less than 300 though!

Rob


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