[subelect]

I have a dumb question regarding putting UF and NM inside a raceway.

Last week one of our well diggers was having a tough time with his trench caving in on him, so he was trying to be a nice guy and assembled the RNC as he was back-hoeing in the water lines. The problem that came up was that he put UF inside it and he did not use expansion joints below the RB panel or the well-head, never mind that he is not a licensed electrician.
I will find out this week, but the boss was saying that we have to remove the UF and install THHN.

Where is it stated that UF can't be inside a raceway the entire length of the wire, which in this case was 40'?

Along the same lines, when I am wiring up a garage in NM and the customer wants an outlet on the exposed side of a pillar, for example 3' down, I put the NM inside EMT with either a EMT-Romex connector at the top or a white plastic insulator. At what point do I have to derate the NM? 334 says that it can be placed inside a raceway to go between floors, but it does not indicate what is the length where you have to derate.

Finally, while installing a new service with a RNC sleeve (18-24" long) above the service entrance, should the NM have the jackets removed or not? I know that I am not allowed to fill the sleeve greater than 60% area, but I have always left the jackets intact until they enter the panel. What section of the NEC tells you to leave the jacket intact or remove it inside the sleeve?

Thanks,
Rick

 

[480sparky]

There's no reason, as long as raceway fill is considered, to disallow UF in a raceway.

NM, however, cannot be put in a raceway if the raceway is in a wet location. 300.5 (B).

Nipple rules are Note 4, Chapter 9.

 

[Celtic]

I don't do well type installs...is there anything about the EGC being insulated?

 

[B4T]

NM, however, cannot be put in a raceway if the raceway is in a wet location. 300.5 (B).

300.5 Underground Installations.​

(A) Minimum Cover Requirements.

Direct-buried cable

or conduit or other raceways shall be installed to meet the
minimum cover requirements of Table 300.5.
​

(B) Wet Locations. ​

​

The interior of enclosures or raceways

installed underground shall be considered to be a wet location.
Insulated conductors and cables installed in these enclosures
or raceways in underground installations shall be
listed for use in wet locations and shall comply with
310.8(C). Any connections or splices in an underground​

installation shall be approved for wet locations.

​

 

[waco]

We run UF and NM in conduit all the time. In fact, I just used EMT to provide protection for NM in an exposed work situation.

If I was going to run conduit anyway, I'd use THHN or THWN because the cost is substantially less, but if the job was more about the UF than the conduit, I'd stick with the UF, assuming the fill isn't exceeded.

I never use expansion joints in buried PVC. Darn.

 

[MDShunk]

Here's a chart of NM and UF cable diameters that has been used by a lot of people to determine conduit fill when pulling NM or UF in raceway:

14-2 NMB .1018
12-2 NMB .1320
10-2 NMB .1917
8-2 NMB .2942
6-2 NMB .3664
14-3 NMB .0740
12-3 NMB .0946
10-3 NMB .1399
8-3 NMB .2507
6-3 NMB .3318
14-2 UF .1405
12-2 UF .1684
10-2 UF .2107
8-2 UF .3610
6-2 UF .4657
14-3 UF .2651
12-3 UF .3078
10-3 UF .4151
8-3 UF .8808
6-3 UF 1.1747

 

[Magnettica]

Here's a chart of NM and UF cable diameters that has been used by a lot of people to determine conduit fill when pulling NM or UF in raceway:

14-2 NMB .1018
12-2 NMB .1320
10-2 NMB .1917
8-2 NMB .2942
6-2 NMB .3664
14-3 NMB .0740
12-3 NMB .0946
10-3 NMB .1399
8-3 NMB .2507
6-3 NMB .3318
14-2 UF .1405
12-2 UF .1684
10-2 UF .2107
8-2 UF .3610
6-2 UF .4657
14-3 UF .2651
12-3 UF .3078
10-3 UF .4151
8-3 UF .8808
6-3 UF 1.1747

That's good that u posted that. I had a discussion earlier and was asked if (2) 14/2 NM's could legally be installed in 1/2" EMT. I'm pretty sure this falls under the 40% fill category and if that's the case one (1) cable is permitted.

 

[subelect]

Thanks.
Rick