Cable clamp required with conduit?

[marrt]

I'm installing an additional circuit in my garage. I'm using flexible conduit and a surface mounted metal box. Is a cable clamp required in the surface mounted box? In general, are cable clamps required when installing cable through conduit? I assume "no" but wanted to confirm.

 

[nkachur]

I'm installing an additional circuit in my garage. I'm using flexible conduit and a surface mounted metal box. Is a cable clamp required in the surface mounted box? In general, are cable clamps required when installing cable through conduit? I assume "no" but wanted to confirm.

I do belive the conduit has to be secured to the box with an appropriate connector. I know with the PVC conduit I am using for my exposed runs I am useing these.

http://www.cooperindustries.com/con...ings/pvc/non-metallic_pvcconduitfittings.html

There should be adaptors for your conduit.

 

[Stuart in MN]

The conduit does need to be secured to the box, but the wires inside the conduit don't require any clamps.

 

[marrt]

Sorry for the confusion. I am securing the conduit to the box with a proper fitting. I was just curious about needing a cable clamp. Unlike a normal NM installation with a metal box for example, there's no easy way to attach a clamp since the conduit fitting is "in the way." Thanks for the response.

 

[Charles (in GA)]

I'm still confused. Are you using some sort of empty flex conduit (the only flex I'm familiar with has the wires permanently installed in the flex most people call it BX) and are you pulling Romex thru the flex?

I know there is waterproof flex that you can pull wires thru, and there is the blue plastic stuff that snaps together and pull wires thru. Is there something else?

Charles

 

['04 Cummins]

I'm still confused. Are you using some sort of empty flex conduit (the only flex I'm familiar with has the wires permanently installed in the flex most people call it BX) and are you pulling Romex thru the flex?

I know there is waterproof flex that you can pull wires thru, and there is the blue plastic stuff that snaps together and pull wires thru. Is there something else?

Charles

It's commonly called greenfield (NEC calls it flexible metallic conduit). It's basically MC cable with no wire pre-installed. Comes in sizes ranging from 3/8" up to 4".

BX hasn't been used for years. It was replaced with MC cable (separate copper grounding conductor).

PVC coated greenfield is called sealtite (liquidtight flexible metallic conduit).

The blue stuff you refer to is called smurf-tube (trade name electrical non-metallic tubing).

There is also liquidtight flexible non-metallic conduit, common manufacture is Carlon. Same as sealtite but with no metal in it.

 

[Speedy Petey]

Sorry for the confusion. I am securing the conduit to the box with a proper fitting. I was just curious about needing a cable clamp. Unlike a normal NM installation with a metal box for example, there's no easy way to attach a clamp since the conduit fitting is "in the way." Thanks for the response.

WHY are you running NM cable in a conduit run??

 

[marrt]

WHY are you running NM cable in a conduit run??

I'm using the blue stuff (smurf tube as someone mentioned). This is in a "Barn" and no electrical inspection is required in my county. However, it's surface mounted and needs some protection. I'm using NM and Smurf because I already had it laying around and it's easy to install (yes, you CAN run NM and even UF in conduit by code, despite the "wives tales" about this).

THHN and EMT or PVC conduit would be better but I don't have any handy.

Stuart in MN answered my specific question.

 

[kursplat]

i can't imagine why plain wire wouldn't need something to hold it and and extra layer of plastic would...

but i await a finding of the court

 

[ishiboo]

I'm using the blue stuff (smerf tube as someone mentioned). This is in a "Barn" and no electrical inspection is required in my county. However, it's surface mounted and needs some protection. I'm using NM and Smerf because I already had it laying around and it's easy to install (yes, you CAN run NM and even UF in conduit by code, despite the "wives tails" about this).

THHN and EMT or PVC conduit would be better but I don't have any handy.

I run NM in PVC conduit in my barn as well. NM is dirt cheap and easier to deal with than individual THHN wires IMO. As long as you don't have complex runs or big fill (I have 2 in 1" PVC) it works really well.

 

[Tim The Tool Man]

I too am confused about what you are asking but then again, I am confused by lots of things! Anyhow do you mean to ask if you should be using one of these?

I would say on that smurf tube, they wouldn't be a bad idea. One ever 3 or 4 feet

 

[Speedy Petey]

(yes, you CAN run NM and even UF in conduit by code, despite the "wives tails" about this).

Wow, thanks for the code class. I had no idea.

 

[Speedy Petey]

I run NM in PVC conduit in my barn as well. NM is dirt cheap and easier to deal with than individual THHN wires IMO.

I'm sorry, but you're nuts!
Individual wires are MUCH easier to deal with in conduit. I think what you mean is it is easier for a DIYer to keep track of things when everything is neatly bundled in cable form.

NM in a sleeve for protection is typical.
NM in a conduit run from box to box is hacky.

 

[Speedy Petey]

i can't imagine why plain wire wouldn't need something to hold it and and extra layer of plastic would...

but i await a finding of the court

THIS is your answer.

ENT (Smurf tube) offers NO more protection than the NM cable itself.