Non metallic flexible conduit question

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black_thorn

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Location
Pa
Hello. Just found this forum yesterday. Seems like a good place for good information.

I have a question about flexible non metallic conduit. Some would call it smurf tube, or carlon. I'm not exactly sure of the manufacturer brand of the conduit I have. It's grey in color. I'm accustomed to using regular EMT with a stub 90? sticking out above drop ceiling for low voltage data.

My question is, is it considered ENT by the NEC. NEC states to support ENT no more than 3' from the box and no more than 3' between supports. Also to use a protector on the end, like an Arlington push on bushing. I wouldnt think this flexible tube would need that, which is kind of why I want to verify that this stuff is considered ENT, or if I'm reading the wrong specifics in the code book.

Thanks for any insight on the matter.
 

GoldDigger

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Location
Placerville, CA, USA
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Retired PV System Designer
ENT is rigid, not flexible.
Normally gray PVC to distinguish it from plumbing PVC and to give it more UV protection.
If anything smurf tube requires more support.
 

black_thorn

Member
Location
Pa
ENT is rigid, not flexible.
Normally gray PVC to distinguish it from plumbing PVC and to give it more UV protection.
If anything smurf tube requires more support.

I appreciate your answer. In the 2008 and 2014 NEC I can't find anything that specifically talks about 'flexible' non metallic tubing. Only non metallic tubing. Do you see anything else in the code that is more specific. I could easily be overlooking the answer.

The code definition of ENT, 362.2 "A nonmetallic, pliable, corrugated raceway of circular cross section with integral or associated couplings, connectors, and fittings for the installation of electrical conductors. ENT is composed of a material that is resistant to moisture and chemical atmospheres and is flame retardant.
A pliable raceway is a raceway that can be bent by hand with a reasonable force but without other assistance."

I also see on the Carlon website they call their version of this tubing ENT.
 

iwire

Moderator
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Location
Massachusetts
I have a question about flexible non metallic conduit. Some would call it smurf tube, or carlon. I'm not exactly sure of the manufacturer brand of the conduit I have. It's grey in color. I'm accustomed to using regular EMT with a stub 90? sticking out above drop ceiling for low voltage data.

My question is, is it considered ENT by the NEC.

Yes 'smurf tube' is ENT.

ent_family_600x275


41lO13EAJ2L.jpg
 

don_resqcapt19

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Staff member
Location
Illinois
Occupation
retired electrician
Flexible non-metallic conduit is covered by Article 356. It is called Liquidtight Flexible Nonmetallic Conduit (LFNC).

The tubing covered by Article 362 is not considered by the code to be a flexible wiring method.
 

GoldDigger

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Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
Flexible non-metallic conduit is covered by Article 356. It is called Liquidtight Flexible Nonmetallic Conduit (LFNC).

The tubing covered by Article 362 is not considered by the code to be a flexible wiring method.
Nope, it is just "pliable" which is not quite as flexible but does not require tools to bend.

Just like in the early days of personal computers there was portable and portative.
Portable meant just what you expect it to mean.
Portative meant that it was too heavy to be carried any significant distance but it had a handle anyway. :)
 

iwire

Moderator
Staff member
Location
Massachusetts
Nope, it is just "pliable" which is not quite as flexible but does not require tools to bend.

No, it is flexible, much much more flexible than LFNC. I have worked with both and LFNC is never more flexible than ENT.

The NEC is just plain nuts on these two items. :D
 

GoldDigger

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Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
No, it is flexible, much much more flexible than LFNC. I have worked with both and LFNC is never more flexible than ENT.

The NEC is just plain nuts on these two items. :D

The NEC is not dealing with what available ENT actually IS. They are giving the minimum specs it has to meet, and that is the pliable part.
If a manufacturer provided ENT that was only pliable, I doubt anybody would buy it over the competition.
 

iwire

Moderator
Staff member
Location
Massachusetts
The NEC is not dealing with what available ENT actually IS. They are giving the minimum specs it has to meet, and that is the pliable part.
If a manufacturer provided ENT that was only pliable, I doubt anybody would buy it over the competition.

No, the NEC is just nuts on this one. :p
 
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