President

[Ray E. Skelton]

Does the NEC require pull boxes at certain intervals on long conduit runs?
I understand the requirement on number of bends but cannot find the distances on pull box locations in long straight conduit runs.

thanks Ray E. Skelton

 

[raider1]

There is no length limit to a conduit run in the NEC, just the number of bends.

I have seen many engineers specifications that require a pull box every 100' in a run of conduit, but this is not an NEC requirement.

Chris

 

[raider1]

By the way welcome to the forum.

Chris

 

[barbeer]

I agree there is no length limitation in the NEC, at some point common sense should prevail(if you only have a 100' fish tape..........), even though we cannot enforce common sense!

 

[Dennis Alwon]

The only limitation is the stress factor on the wire. Obviously a 1 mile pull will create a lot more stress on a wire that is being pulled 100 feet.

 

[480sparky]

The only limitation is the stress factor on the wire. Obviously a 1 mile pull will create a lot more stress on a wire that is being pulled 100 feet.

Another limitation is how long your fish tape/rope is, as well as the length of conductor you can obtain.

 

[C3PO]

Another limitation is how long your fish tape/rope is, as well as the length of conductor you can obtain.

Or how powerful your shop vac is. :smile:

 

[480sparky]

Or how powerful your shop vac is. :smile:

Couple it with a compressor on the other end.... I've had to do that on occasion.

 

[raider1]

Couple it with a compressor on the other end.... I've had to do that on occasion.

I have had to do that as well.

Chris

 

[C3PO]

Couple it with a compressor on the other end.... I've had to do that on occasion.

Never done that. Good idea.

 

[mivey]

I could not figure out the title until I read your profile. Welcome to the forum Mr. President!:smile:

 

[growler]

I agree there is no length limitation in the NEC, at some point common sense should prevail(if you only have a 100' fish tape..........), even though we cannot enforce common sense!

For long pulls useing a fish tape takes up to much time so you blow lines in the conduit. You can put 500 ft. of line in a conduit in about 5 seconds ( and it gets all the gravel out so watch yourself).

 

[barbeer]

For long pulls useing a fish tape takes up to much time so you blow lines in the conduit. You can put 500 ft. of line in a conduit in about 5 seconds ( and it gets all the gravel out so watch yourself).

As my nine year old would say in a very matter of fact voice........."Yes I know!"

 

[LarryFine]

Or how powerful your shop vac is. :smile:

Good point. Our shop-vac really sucks.