Three Phase in Residential

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ronnie

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Where in the NEC does it state that I have to install the conductors to a three phase range in conduit? This is a 120/208 3 phase unit. Can I buy a 3 phase assemblied romex with 3 ungrounded conductors,one grounded conductor and one equipment ground?
 
mark henderson said:
Chris that is pretty vague. Dont you think? So would 300.3b apply? They dont make three phase romex so you are limited to mc or pipe.
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The NEC does not prevent the use 3-phase NM cable in this instance. It is not the "NEC's" problem that the product is not manufactured.
 
RIght I am not holding the NEC responsible. I was just trying to clearify for the OP. and 300.3b seemed to apply just did not know if there was something i was missing.
Mark.:grin:
 
Chris that is pretty vague. Dont you think?
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I apoligize if I came across as harsh, I was just answering the question about where in the NEC does it say you have to install the conductors to a three phase range in conduit. Again there is no place in the NEC that requires that you install the conductors to a three phase range in a conduit, only that you use a wiring method from Chapter three.

So would 300.3b apply?
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If the wiring method is non-ferrous then take a look at 300.3(B)(3)

They dont make three phase romex so you are limited to mc or pipe.
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Both of the methods you mentioned are Chapter three wiring methods. My point was there is nothing in the NEC that requires you to use conduit in the situation that was laid out in the OP.

Chris
 
I dont mean to be harsh either you have answered questions for me before.:)
I looked at 300.3b3 and 300.20b so am I wrong in thinkig you can parrell this run in a non-metalic cable?:-?

Mark
 
ronnie said:
Can I buy a 3 phase assemblied romex with 3 ungrounded conductors,one grounded conductor and one equipment ground?
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Romex?
Why not some flavor of SE?

This is, of course, assuming that romex/SE is even allowed in the area you are from....so, where ya from?
 
I looked at 300.3b3 and 300.20b so am I wrong in thinkig you can parrell this run in a non-metalic cable?
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The conductors of circuits using nonferrous wiring methods can be run in different cables as long as you conform with section 300.3(B)(3)

Chris
 
I can't remember ever seeing a residential 3 phase service (at least not in my area). Are there any POCO's throughout the US that do this or is it just me not seeing outside the box ?
 
goldstar said:
I can't remember ever seeing a residential 3 phase service (at least not in my area).
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I just did 6 of them in Hudson County...then again, it's a huge resi. complex.

If you head out to Watchung area, you see them on SFH....well you won't actually see anything, but they are there ;)
 
Celtic,

I can understand a POCO bringing a large 3-phase service into a housing complex but each condo/apt doesn't get a 3-phase panel do they ? Also, is the voltage 120/208 or 120/240 ?

Phil
 
goldstar said:
I can't remember ever seeing a residential 3 phase service (at least not in my area). Are there any POCO's throughout the US that do this or is it just me not seeing outside the box ?
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We have some big bucks custom homes with 3 phase service. Last one I remember was a 1200 amp 208Y/120. Even had a mini central plant in the basement.
 
goldstar said:
Celtic,

I can understand a POCO bringing a large 3-phase service into a housing complex but each condo/apt doesn't get a 3-phase panel do they ? Also, is the voltage 120/208 or 120/240 ?

Phil
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About 6 - 9 of them did.
If I recall they were @ 120/240V 200A
 
I've come across several single family residences with 3 phase 120/240V services and all have been from a Delta XFMR meaning there is a wild leg to deal with. The POCO's want the wild leg on C phase in the meter socket and the AHJ's want it on B phase at the disconnect. I always wonder how many DYIers unsuspectingly add a circuit from B phase and wonder why there is the smell of smoke in the air.
 
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