wayne123
Senior Member
- Location
- North Carolina
Can someone tell me if there is a code reference that does not allow NM to be run in carlon or seal tite flex for A/C connections.
NM in Carlon flex
- Thread starter wayne123
- Start date
- Status
- Location
- Illinois
- Occupation
- retired electrician
Re: NM in Carlon flex
Wayne,
NM is suitable for dry locations only. In my opinion any raceway installed outdoors is a wet location. Also under the current code wording in the xxx.22 sections of all of the raceway articles, cables are not permitted in raceways unless specifically permitted in the cable article. There is no such permission in Article 334. Note, that this rule will be changed in the 2005 code. In the 2005 code, cables will be permitted in raceways unless there is a specific prohibition in the cable article.
Don
Wayne,
NM is suitable for dry locations only. In my opinion any raceway installed outdoors is a wet location. Also under the current code wording in the xxx.22 sections of all of the raceway articles, cables are not permitted in raceways unless specifically permitted in the cable article. There is no such permission in Article 334. Note, that this rule will be changed in the 2005 code. In the 2005 code, cables will be permitted in raceways unless there is a specific prohibition in the cable article.
Don
wayne123
Senior Member
- Location
- North Carolina
Re: NM in Carlon flex
Thanks Don. I have been doing this for years and have never been flagged on it. I used that argument on the inspector and it worked. He said only a few inspectors red flag it and he was not one of them. I really think that since it is in carlon that it would get wet and I guess the NEC Board agrees with that since they are going to allow it in 2005.
Thanks Don. I have been doing this for years and have never been flagged on it. I used that argument on the inspector and it worked. He said only a few inspectors red flag it and he was not one of them. I really think that since it is in carlon that it would get wet and I guess the NEC Board agrees with that since they are going to allow it in 2005.
ryan_618
Senior Member
- Location
- Salt Lake City, Utah
Re: NM in Carlon flex
Don I agree, but where does it say that in the code?
bphgravity
Senior Member
- Location
- Florida
Re: NM in Carlon flex
Section 334.10(A)(1).
ryan_618
Senior Member
- Location
- Salt Lake City, Utah
Re: NM in Carlon flex
Thanks Bryan. I looked at 334.10 about 5 times and glossed right over it!
Thanks Bryan. I looked at 334.10 about 5 times and glossed right over it!
- Location
- Illinois
- Occupation
- retired electrician
Re: NM in Carlon flex
Wayne,
Don
Wayne,
The 2005 code will allow NM in raceways, but it still is not permitted in wet locations. Outside raceways are wet locations and NM is not permitted. That won't change in 05 code.
Don
- Location
- Illinois
- Occupation
- retired electrician
Re: NM in Carlon flex
jap2525,
Don
jap2525,
In my opinion, the interior of all raceways that are installed in wet locations is also a wet location and requires the use of cables or conductors that are listed for use in wet locations.
Don
Re: NM in Carlon flex
IMO,I feel like liquid tight metallic or nonmetallic flex is used just for that purpose,to keep the liquid out of the raceway,be it rain or any other liquid.If we are not concerned with keeping the liquid out of the raceway we could use regular greenfield flex in wet locations.
IMO,I feel like liquid tight metallic or nonmetallic flex is used just for that purpose,to keep the liquid out of the raceway,be it rain or any other liquid.If we are not concerned with keeping the liquid out of the raceway we could use regular greenfield flex in wet locations.
peter d
Senior Member
- Location
- New England
Re: NM in Carlon flex
jap2525,
Actually, you can use FMC in wet locations, as long as you use conductors with a wet rating (such as THWN) and arrange the raceway so that water will not enter the enclosures to which it is connected.
Article 348.12 (1)
Water will inevitably get into outdoor and underground raceways no matter how hard we try to prevent it. There is nothing that can be done to stop condensation, or the ground shifting and opening up a conduit. That is why they are considered a wet location.
-------
Why would you use NM inside LFNMC for an A/C whip when you can easily use a few pieces of THHN?
[ September 23, 2004, 02:20 PM: Message edited by: peter d ]
jap2525,
Actually, you can use FMC in wet locations, as long as you use conductors with a wet rating (such as THWN) and arrange the raceway so that water will not enter the enclosures to which it is connected.
Article 348.12 (1)
Water will inevitably get into outdoor and underground raceways no matter how hard we try to prevent it. There is nothing that can be done to stop condensation, or the ground shifting and opening up a conduit. That is why they are considered a wet location.
-------
Why would you use NM inside LFNMC for an A/C whip when you can easily use a few pieces of THHN?
[ September 23, 2004, 02:20 PM: Message edited by: peter d ]
peter d
Senior Member
- Location
- New England
Re: NM in Carlon flex
Jap2525, sorry, I wasn't addressing that comment towards you, and I edited my post accordingly.
Jap2525, sorry, I wasn't addressing that comment towards you, and I edited my post accordingly.
Re: NM in Carlon flex
Water will inevitably get into outdoor and underground raceways no matter how hard we try to prevent it. There is nothing that can be done to stop condensation, or the ground shifting and opening up a conduit. That is why they are considered a wet location.
who is they? where does it say the inside of liquidtight nonmetallic flexible conduit is a wet location?
Water will inevitably get into outdoor and underground raceways no matter how hard we try to prevent it. There is nothing that can be done to stop condensation, or the ground shifting and opening up a conduit. That is why they are considered a wet location.
who is they? where does it say the inside of liquidtight nonmetallic flexible conduit is a wet location?
Re: NM in Carlon flex
don't get me wrong I agree with all that is being said except for the fact that the inside of the nonmetallic flex is a wet location.For that matter if it hailed on the roof enough to damage the roof and the roof started to leak would our houses have to be wired inside as a wet location? no,we fix the roof to shield the rain from coming in or in this case install the nm in a flexible conduit that is supposed to keep the water out if installed properly.
don't get me wrong I agree with all that is being said except for the fact that the inside of the nonmetallic flex is a wet location.For that matter if it hailed on the roof enough to damage the roof and the roof started to leak would our houses have to be wired inside as a wet location? no,we fix the roof to shield the rain from coming in or in this case install the nm in a flexible conduit that is supposed to keep the water out if installed properly.
- Location
- Illinois
- Occupation
- retired electrician
Re: NM in Carlon flex
Unless the conduit or other raceway is purged and pressurized, it will end up with water in it, if it is installed in a wet location. Some of this water is caused by condensation. The conduit "breathes", that is air moves in and out because of changes in atmospheric conditions. When there is moist air in the raceway, and the temperature drops, the moist air becomes liquid water. There in not a lot of air movement, so this liquid does not readily evaporate and it builds up over time.
I stick to my opinion that the inside of all raceways that are installed in wet locations is also a wet location. I can't tell you how many times that I have taken liquid tight flexible metal conduit apart to find almost no metal left inside due to rusting.
Don
Unless the conduit or other raceway is purged and pressurized, it will end up with water in it, if it is installed in a wet location. Some of this water is caused by condensation. The conduit "breathes", that is air moves in and out because of changes in atmospheric conditions. When there is moist air in the raceway, and the temperature drops, the moist air becomes liquid water. There in not a lot of air movement, so this liquid does not readily evaporate and it builds up over time.
I stick to my opinion that the inside of all raceways that are installed in wet locations is also a wet location. I can't tell you how many times that I have taken liquid tight flexible metal conduit apart to find almost no metal left inside due to rusting.
Don
A
a.wayne3@verizon.net
Guest
Re: NM in Carlon flex
isn`t nm comprised of thhn conductors so why is this an issue?
isn`t nm comprised of thhn conductors so why is this an issue?
- Location
- Illinois
- Occupation
- retired electrician
Re: NM in Carlon flex
Don
[ September 23, 2004, 07:56 PM: Message edited by: don_resqcapt19 ]
Because the code says NM is not permitted in wet locations. And if the conductors are THHN, they are not suitable for wet locations
Don
[ September 23, 2004, 07:56 PM: Message edited by: don_resqcapt19 ]
- Location
- Bremerton, Washington
- Occupation
- Master Electrician
Re: NM in Carlon flex
Don, are the NM conductors THHN or rated at 90 deg C? There is no printing on the insulation. Which means they can't be used for general wiring, if say one had a lot of spare time and want to strip the NM jacket off...
Don, are the NM conductors THHN or rated at 90 deg C? There is no printing on the insulation. Which means they can't be used for general wiring, if say one had a lot of spare time and want to strip the NM jacket off...
- Location
- Illinois
- Occupation
- retired electrician
Re: NM in Carlon flex
Tom,
I really have no idea what the internal NM conductors are, becuase as you said, they are not marked. The only thing that we know about them is that they are rated for 90?C and the wire is one of the types listed in Table 310.13 (334.112), and that the cable cannot be used in wet locaitons [334.12(10)(d)].
Don
Tom,
I really have no idea what the internal NM conductors are, becuase as you said, they are not marked. The only thing that we know about them is that they are rated for 90?C and the wire is one of the types listed in Table 310.13 (334.112), and that the cable cannot be used in wet locaitons [334.12(10)(d)].
Don
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