Cable

[Btrox]

How do I calculate what conduit to use for cable.
I'm putting say 3---- 1/2" dia. cables in conduit. Say each cable consists of 3#14 with GND.

 

[jaylectricity]

Chapter 9 is a start.

I'm embarrassed to admit that I don't know since I've never put more than two NM-B cables in a single conduit so I've never had to look it up.

 

[fmtjfw]

See Chap 9. note 5

 

[John120/240]

Usually we don't put Romex in conduit. Is this a wet location ? If so to be right you would have to use a wet location rated wire. UF cable or THHN/THWN . What is the length of your conduit run ? More specifics PLEASE.

 

[jaylectricity]

I'm going to guess we're talking about running a bunch of circuits to a new addition or garage or something. I think it would be cheaper to run THHN/THWN anyway.

Or are you doing that thing where you put all the branch circuit cables into a 2" pipe into the top of a panel because there's nowhere to staple above the panel. Maybe because it's concrete or whatever.

Again, probably cheaper to pound some plywood to the concrete above the panel.

But this is merely speculation without any good details.

 

[Btrox]

Thanks,
I do control work so it's running control cable to/from machines, and looking to protect control cables around machines or running conduit with multiple control cable to a machine, from 4 to 20 conductor cable.

 

[petersonra]

Thanks,
I do control work so it's running control cable to/from machines, and looking to protect control cables around machines or running conduit with multiple control cable to a machine, from 4 to 20 conductor cable.

Generally if you can fit it in, it usually meets the minimum code requirements for fill space.

It is hard to fit more cables into a conduit than are allowed by the rules. You have to really try.

 

[J.P.]

So all low volt then? I don't know if it's strictly legal but the Data and Fire guys don't leave much room in their pipe and they pass inspection........

I have ran a bit myself but I will admit to just leaving room for more if the need arises. Nobody has ever said anything, but that doesn't mean I'm right