pullbox question....

[mjimenez]

I would like to know,is there a standard mentioned in the NEC the maximum distance of 2" conduit (straight run) before installing a pull box?

 

[raider1]

Welcome to the forum.

There is not an NEC specified distance in a straight run at which a pull box must be installed.

I have seen engineering specs that required a pull box every 100' but this is not required in the NEC.

Chris

 

[480sparky]

What raider1 said.

Usually there's limits stated in construction docuements, but the NEC says not a word about it.

 

[infinity]

If the run is vertical there are requirements outlined in 300.19 for conductor support which could require boxes as close as 35' apart even in a straight run of conduit.

 

[raider1]

If the run is vertical there are requirements outlined in 300.19 for conductor support which could require boxes as close as 35' apart even in a straight run of conduit.

Good point, I wasn't thinking vertical.

Chris

 

[ohmhead]

Well dont forget kinda on the vertical riser you also need conductor support which really means a box its not a box per nec its a support at different lengths on your riser going up .

You install a box to install cable or conductor supports we use the wedge type these are custom made when you order them and there made from wood .

These are bushings specially made that each conductor gos thur and are held up by the wooden wedge .

 

[480sparky]

Well dont forget kinda on the vertical riser you also need conductor support which really means a box its not a box per nec its a support at different lengths on your riser going up .

You install a box to install cable or conductor supports we use the wedge type these are custom made when you order them and there made from wood .

These are bushings specially made that each conductor gos thur and are held up by the wooden wedge .

I've heard stories about people who don't understand that. I had a guy in my apprentice class years ago who said they ran wires up a cell phone tower and just installed standard pull boxes. Once the cable was installed, it was cut and the whole shebang ran out all over the ground.

He said it looked like a pot of cooked spaghetti.

 

[ohmhead]

Well the most fun is taking the rolls of 600 mcm up the buck hoist and when your up 36 stories in that electrical room holding it back as your letting it drop down 90 foot at a time thur each box ,we use a wire break its lots of fun !