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#200601 - 04/09/11 05:46 PM 480 V Branch circuit and 120V branch circuit
lite bulb Offline
Member

Registered: 02/12/06
Posts: 77
Loc: wilm,de.
Can 480V and 120V branch circuits share the same raceway. The 480V branch circuit is being fed from the MCC panel operates four .50 amp vibrators and the 120V is being fed from the lighting panel for a flood light, both go to a common jbox within the same room then from there they go underground outside the building to the vibrators and flood light.

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#200605 - 04/09/11 08:42 PM Re: 480 V Branch circuit and 120V branch circuit [Re: lite bulb]
George Little Offline
Member

Registered: 01/18/04
Posts: 1492
Loc: Michigan USA
And the answer is: Yes, and the code reference is Article 300 Section 300.3(C)(1). 2008 NEC
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George Little

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#200626 - 04/10/11 06:20 PM Re: 480 V Branch circuit and 120V branch circuit [Re: lite bulb]
lite bulb Offline
Member

Registered: 02/12/06
Posts: 77
Loc: wilm,de.
Thanks George for the reply.

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#200638 - 04/11/11 06:23 AM Re: 480 V Branch circuit and 120V branch circuit [Re: lite bulb]
harold endean Offline
Member

Registered: 02/16/02
Posts: 2248
Loc: Boonton, NJ
Yeah,

Now how about a 120/240 volt and a 12 volt circuit?

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#200642 - 04/11/11 05:12 PM Re: 480 V Branch circuit and 120V branch circuit [Re: lite bulb]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9012
Loc: Estero,Fl,usa
Sure as long as you don't want it to be class 2 or 3.
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#200644 - 04/11/11 05:31 PM Re: 480 V Branch circuit and 120V branch circuit [Re: lite bulb]
George Little Offline
Member

Registered: 01/18/04
Posts: 1492
Loc: Michigan USA
You beat me to it Greg. As for the substantiation it would be 725.48.
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#200662 - 04/13/11 07:19 AM Re: 480 V Branch circuit and 120V branch circuit [Re: lite bulb]
harold endean Offline
Member

Registered: 02/16/02
Posts: 2248
Loc: Boonton, NJ
Greg,

Now would you please tell that to some of the EC's in my area. They put 16 ga bell wire in with 120 volt wiring and think that it is OK. I also inspect premade shelters for cell towers and in there they have the low voltage bell wire mixed in with the service conductors. I guess the are using the sec. 725.48.

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#200666 - 04/13/11 10:15 AM Re: 480 V Branch circuit and 120V branch circuit [Re: lite bulb]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9012
Loc: Estero,Fl,usa
How are they putting them together? You could make the argument that if both are cables you have separation but they still have to terminate in separate compartments.

Using the class 1 rules basically means you are using low voltage on a chapter III wiring method.
"Bell wire" can't be used in Class 1.
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Greg Fretwell

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#200678 - 04/13/11 08:59 PM Re: 480 V Branch circuit and 120V branch circuit [Re: lite bulb]
watersparkfalls Offline
Member

Registered: 03/08/05
Posts: 210
Loc: Washington...Not DC
if two different systems enter a jbox, they still have to have a divider?

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#200719 - 04/16/11 11:32 AM Re: 480 V Branch circuit and 120V branch circuit [Re: lite bulb]
harold endean Offline
Member

Registered: 02/16/02
Posts: 2248
Loc: Boonton, NJ
Greg,

The cell tower pre-made control box had bell wire in the same cabinet with service cable and there were no separate boxes, areas or compartments. Next time I inspect a cell tower trailer, I will see if I can get a picture.

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