?
Monday, March 11, 2019
Question:
Re: CQD answer published Monday, February 25, 2019 -Article 725 Class 2 Wiring
1) Hi Charlie: I'm taking an alternate view on the answer Chapter's 5, 7, 8, 9 in the NEC modify or amend the general rules in prior chapters. If you use a Chapter 3 covered raceway, then it must be installed and supported per the salient requirements since there's no mention of it under Article 725, Class 2 wiring. In fact, due diligence would extend to marking such raceway outlets stating that only Class 2 wiring is permitted. If metal raceways are used and part of the GEC, then all bonding and grounding is still required. The raceway needs to be intact as well. Often times, Class 2 wiring is wire-tied for support to other structures. This is a violation since wire-ties are not Listed for that purpose. Suitable straps, etc. are required and not supported from other electrical raceways, etc. Wire-ties or Tie-Wraps used outside of enclosures exposed to UV tend to get brittle and lose mechanical integrity. An example of labeling raceways to restricted type wiring can be found in Art. 504, Intrinsic Safety. The only place where you wouldn't is a Listed raceway section, such as a RMC stub, is used as a feed-though to facilitate ease of installation. Best Regards, Nick Abbatiello
2) I have been a long time viewer and a good friend of the Late Charlie Trout. He was a great person, miss seeing him and his Carole at the IAEI Western Section Meetings and I am happy to see that NECA is still carrying on his legacy. In the answer on Friday, February 22nd you referenced that there was no reference to Section 300.11 in 725.3. With Article 725 not modifying the requirements in chapter three it would appear the requirements for the raceway articles would apply. Article 725, the limited energy articles and the Chapter 8 cables usually do not require those cables to be in a raceway. It has been my thought that if a raceway is installed, than the requirements of that raceway article would apply. Thank you to NECA for continuing this valuable service. Dave
A
Answer:
Hey Nick and Dave thanks for your follow up comments and the compliment, we all miss Charlie.
1) Actually Chapters 5, 6, and 7 can supplement or modify Chapters 1 through 7. Regarding cable ties, they are specifically allowed as stated in 725.24.
1 & 2) Comments were somewhat expected and there are different points of view that the AHJ will need to consider when making the decision.
As we previously mentioned 300.11 is not one of the sections included in 725.3 so it is not required to be followed for everything in Article 725. For Class 1 circuits, Part I of Article 300 (which includes 300.11) and Chapter 3 for the appropriate wiring method is specifically required as stated in 725.46. Section 725.130 allows conductors on the load side of a Class 2 or Class 3 power supply to be installed using either Chapter 3 wiring methods, including the rules in Part I of Article 300 [725.130(A)], or by using Class 2 or Class 3 cables [725.130(B).
So, if Article 725 cables are used, they are not required to follow the specific supporting rules in 300.11 but must be insulated using an appropriate cable in 725.179. They are not a wiring method in Chapter 3, such as individual conductors in a raceway and are not installed using the Chapter 3 rules as stated in 725.130(A) - even though they happen to be in a raceway. This is a very convoluted path, somewhat like picking fly specks out of black pepper, and might not be interpreted the same way by all AHJ's. A public input, or maybe several, to make this clearer would be helpful for the 2023 NEC. If a CMP3 of CMP16 member has more background information or different interpretation please send that in.