ROMEX IN PVC

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j rae said:
Can I run 6/3 romex in pvc??
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Other than for a short length of additional physical protection or a sleeve through masonry or some similar application, my question is why would you want to?

If you are using raceway wiring methods it cost less to pull individual conductors than to pull cables through.
 
kwired said:
Other than for a short length of additional physical protection or a sleeve through masonry or some similar application, my question is why would you want to?

If you are using raceway wiring methods it cost less to pull individual conductors than to pull cables through.
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The price of #6THHN verses 6/3 romex is not much different and the conduit id big enough>
 
Other than mentioned by Kwired, why are you installing NM cable in PVC?
Is it for a hot tub that will go on the outside of the wall?
 
j rae said:
The price of #6THHN verses 6/3 romex is not much different and the conduit id big enough>
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NM cable is a 60C conductor.

If you are running a 50 amp circuit and you use THHN/THWN you can use 8 AWG. Just something to consider. Also you can often use as small as 10 AWG for the neutral.

I have started running more raceways in place of 6AWG NM cable than I used to. I get tired of buying large NM cable and having so many 10 to 20 foot pieces left over that are hard to find a use for. But I do use more 6 AWG for other applications and usually buy it on bigger quantity reels. I guess if I used more large sizes of NM cable more often I may look at this differently.
 
No it cannot be in PVC if the conduit is in a wet location or damp locations. Yes, NM is allowed in PVC if the fill is observed and it is not in damp or wet location. You may also sleeve NM in PVC.
 
kwired said:
NM cable is a 60C conductor.

If you are running a 50 amp circuit and you use THHN/THWN you can use 8 AWG. Just something to consider. Also you can often use as small as 10 AWG for the neutral.
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Would this not violate 110.14C1a (2008) ? I am guessing that the equipment that he is running power to would be 55amps or less.

Wouldn't he have to use the 60C column for equipment rated 100amps or less? I know he can use higher temp wire 110.14C1a2 but it would have to be from 60C column..Correct?

Dan
 
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Dan, if the terminations are rated 75C as most are and the wire is rated at least 75C then you can use the 75C rating. The 60C rating for 100 amps or less is only if we don't know the termination rating of we know that the termination is 60C not 75C.
 
squaredan said:
kwired said:
NM cable is a 60C conductor.

If you are running a 50 amp circuit and you use THHN/THWN you can use 8 AWG. Just something to consider. Also you can often use as small as 10 AWG for the neutral.
Click to expand...

Would this not violate 110.14C1a (2008) ? I am guessing that the equipment that he is running power to would be 55amps or less.

Wouldn't he have to use the 60C column for equipment rated 100amps or less? I know he can use higher temp wire 110.14C1a2 but it would have to be from 60C column..Correct?

Dan
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You can use #8 Thhn/Thwn for a 50 circuit if you run conduit and pull individual conductors.
If you use Romex then you have to use the 60d C column and you'd have to pull #6 for a 50 amp Circuit.
I personally never reduce the Neutral Size but thats just me.
JAP.
 
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jap said:
I personally never reduce the Neutral Size but thats just me.
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If the load is not there, then why?

Take a 50 amp circuit for a range, neutral load is likely less than 10 amps, maybe even less than 5 amps in most cases, but we must still have a neutral sized at least to 250.122. 10 AWG has plenty of capacity for the load it will see.
 
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Dennis Alwon said:
Dan, if the terminations are rated 75C as most are and the wire is rated at least 75C then you can use the 75C rating. The 60C rating for 100 amps or less is only if we don't know the termination rating of we know that the termination is 60C not 75C.
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yeah i was toying with that idea and I did read 110.14C1a3 also, but thought i give it go anyway..Thanks for the reply Dennis..

Dan
 
Hey Kwired that post of " I personally never reduce the Neutral Size but thats just me" was not by me even though it says my name.. I think i messed up the Quote in my post and somehow it just added my name..Sorry..
 
kwired said:
If the load is not there, then why?

Take a 50 amp circuit for a range, neutral load is likely less than 10 amps, maybe even less than 5 amps in most cases, but we must still have a neutral sized at least to 250.122. 10 AWG has plenty of capacity for the load it will see.
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I just never do.
Jap.
 
-NEC 2011
- Use the Example of the 50 A Range circuit
- 250.122 sizes Equipment Grounding Conductors (EGC) not Grounded (neutral) conductors
- 210.19(A)(3)Ex.2 allows the neutral conductor for household cooking appliances to be smaller than the ungrounded conductors (70% of the branch circuit rating, but not less than 10 AWG, i.e.
.70 X 50A = 35A).

-If the 50A Range branch circuit is wired with individual conductors in conduit with THWN (75C) or
THHN (90C) insulation, then: 310.15(B)(16) Ungrounded conductors = 8 AWG, Neutral conductor = 10 AWG, Equipment Grounding Conductor (EGC) = 10 AWG (T250.122).

-If an SE cable with 75C insulation is used, then conductors sizes would be the same.
Note: NEC 2008 required SE used in Interior Installations to follow NM rules including 334.80 Ampacity, i.e. 60C column in T310.16. NEC 2011 excludes SE from 334.80 Ampacity requirements.

- If an NM cable is used then from 60C column: Ungrounded Conductors = 6 AWG, Neutral conductor = 8 AWG, and EGC is still = 10 AWG.
 
I am getting used to posting here. I think I may have deleted the post I was trying to send. If this is a repeat post, I apologize.

- NEC 2011

-Reference the example of the 50A Range circuit

-T250.122 sizes the Equipment Grounding Conductor (EGC) not the Grounded (neutral) Cond.

-210.19(A)(3)Ex. 2 allows the neutral conductor for household cooking appliances to be smaller than the ungrounded conductors ( 70% of Branch Circuit rating, but not less than 10 AWG, i.e.
.70 X 50A = 35A).

- If a 50A Range branch circuit is wired in conduit with individual conductors with THWN (75C) or THHN (90C) insulation, then: 310.15(B)(16) Ungrounded Conductors = 8 AWG, Neutral conductor = 10 AWG, Equipment Grounding Conductor(EGC) = 10 AWG (T250.122)

-If an SE cable with 75C insulation is used, conductor sizes would be the same.
Note: NEC 2008 required SE used in Interior Installations to follow NM rules including 334.80 Ampacity (60C column in T310.16). NEC 2011 excludes SE from 334.80 Ampacity requirements.

- In an NM cable is used then from 60C column: Ungrounded Conductors = 6 AWG, Neutral Conductor = 8 AWG, and EGC is still = 10 AWG.
 
I believe a NM 6/3 w/ground comes with a full size #6 Neutral not a #8.
And regardless of all the calculations I never pull a reduced neutral but thats just me.
 
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