Chris Kennedy: 725.3 vs. 300.5

[George Stolz]

Chris, in your signature it says

still wondering if 725.3 supercedes 300.5

IMO, yes, it does. Since 300.5 isn't mentioned (that I could see) in Article 725, then 725.3 says it is inapplicable.

Now, pending the results of this discussion, change your signature.

 

[chris kennedy]

OK George, you guys have been a great deal of help. After "lurking" for months here one of my first questions was about this. I brought it up in other posts and it was never resolved.

I have a 3/4 RNC intended for Tstat control. According to 300.5 column 3 that raceway shall be 18" to the top. If the wire was installed before underground inspection then it could be just under the sod. See what I mean?

Signature edit as per Mr. Stolz

 

[George Stolz]

I'd say 725.3 applies, and it could be shallower. Maybe not the best idea, but doable, IMO.

I love the Mod Squad

Now, that's just unsettling, try again.

 

[chris kennedy]

I'd say 725.3 applies, and it could be shallower. Maybe not the best idea, but doable, IMO.

300.5 column 3 says

Raceways listed for direct burial.... No mention of what might be in it.
I'm sorry this is a non issue

 

[hbiss]

I really don't know why there is a question here. 725.3(E) quite clearly states that "only those sections of Article 300 reference in this article shall apply to Class 1, Class 2 and Class 3 circuits".

Nowhere in 725 is there a reference to 300.5. So as far as the NEC is concerned, your CL3 or CL2 thermostat wire, even though it's in conduit can be treated as direct burial with no cover requirements.

Raceways listed for direct burial.... No mention of what might be in it...

No, there is no mention of what might be in it. It's automatically assumed that because this is Chapter 3 it would be Class 1. The cover requirements are to protect the Class 1 conductors not the conduit.

The NEC does not specify cover requirements for buried LV wiring with the odd exception of irrigation and landscape wiring that is only mentioned in column 5 of Table 300.5. This is in direct contradiction with 725.3(E) and there has always been a debate over column 5's validity.

-Hal