NEC vs. UL

[weressl]

Question:

Can UL listing over-ride the NEC?

If an equipment or machinery is a listed product would any and all of the installation methods, OCP ratings and configurations, wiring methods and use, rating, needs to comply with the NEC provisions?

 

[augie47]

I sure hope so.
To me NEC 90.7 covers that.
I've seen a lot of UL assemblies and just looking at the starters you immediately see where the wire sizes, etc. don't meet NEC

 

[weressl]

I sure hope so.
To me NEC 90.7 covers that.
I've seen a lot of UL assemblies and just looking at the starters you immediately see where the wire sizes, etc. don't meet NEC

What bothers me are two things - for now -:

A UL stamp could be for various purposes, permitting a certain mode of use, but not intended for others.

The following quote from the abovementioned section:
..... listed by a qualified electrical testing laboratory that is

recognized as having the facilities described in the preceding
paragraph and that requires suitability for installation in​

accordance with this Code.

What I am suggesting that not ALL UL listings requires suitability for installlation in accordance with the Code. Many of the UL Testing standards are developed in response to ANSI, IEEE, NEMA standards and there is a continuing disconnect between these materials. There IS no harmonization effort exist between theese bodies of agencies and organizations. There is some, but it is amorphous and not set, publicized, regulated, enforced or controlled, in other words, not reliable.

 

[iwire]

Virtually no listed utilization equipment would 'meet the NEC'.