Heat Trace Cable

[rayp1]

1. Is NEC Article 427 only article apply to electric heater type MI cable for pipe heating? For example, MI article 332 does not apply.


2. NEC 427.23 (2011) requires electric heating equipment shall be listed and have a grounded conductive covering for an effective ground path. This implies the heater cable shall be listed to have the seamless metallic alloy (corrosive resistant with high nickel content) covering provide return path for the OCD. We are waiting for the MFG to prove their product is properly listed to perform as an EGC.

a. How can we verify with the MFG future submitted documents that their product is properly listed and tested?


b. Can it be any lab Canada versus UL?

Thank you for the advise, limited experience in specialty material and this is critical.

 

[renosteinke]

First off, the consumer needs to remember that they are a user - not a designer, test lab, or instant expert.

I don't know how you infer some of the things you infer. Heat trace cables often have grounded jackets that you cannot see - not without dissecting the cable. These shields may be a foil wrapping, or a fine braid.

I happen to have two entirely different listed heat trace cables here. One is the 'traditional' sort made by EasyHeat, while the other is a 'self-regulating' type made by Raychem. Neither has a visible grounded wrapping. Both carry UL labels.

Your solution is to look for the label of someone you - or your AHJ - trusts. UL, CSA, whatever. You can further be reassured if there is either a built-in GFCI or a 3-prong plug.