UL approval on equipment

[usconstruction]

I am a General Contractor and have a customer who uses GPU(Ground Power Units) to start turbo prop aircraft in a project I just built. This is a portable device that plugs into a 480V receptacle we provide. The GPU does not have a UL approval and the Electrical Engineer says NEC requires All equipment to have UL approvals to meet code. Is this true?

This issue came up when the plug on the device shorted out because the operator pulled the wires out of the male receptacle. The circuit breaker in the electrical inside 480v panel did not trip but the main outside distribution panel breaker for the 480v service did trip. The engineer said that could happen because it may bne more sensitive. Shouldn't the inside smaller breaker trip before the larger outside breaker trip??

This is a South Florida project completed this year.

 

[roger]

The NEC doesn't require all equipment to be third party listed but local codes might. The tripping problem sounds like a breaker setting, is the main an electronic breaker and does the service have GFP?

Roger

 

[mgookin]

I am a General Contractor and have a customer who uses GPU(Ground Power Units) to start turbo prop aircraft in a project I just built. This is a portable device that plugs into a 480V receptacle we provide. The GPU does not have a UL approval and the Electrical Engineer says NEC requires All equipment to have UL approvals to meet code. Is this true?

This issue came up when the plug on the device shorted out because the operator pulled the wires out of the male receptacle. The circuit breaker in the electrical inside 480v panel did not trip but the main outside distribution panel breaker for the 480v service did trip. The engineer said that could happen because it may bne more sensitive. Shouldn't the inside smaller breaker trip before the larger outside breaker trip??

This is a South Florida project completed this year.

The NEC covers building & premises wiring and stops at that receptacle. Since your GPU is cord & plug connected, the NEC does not apply to it. However that does not mean some other requirement, such as OSHA or otherwise, applies to that GPU and possibly requires NRTL listing. A common misconception is that things have to be "UL Listed" when in fact there are many Nationally Recognized Testing Laboratories (NRTL's) which are acceptable to provide listing services.

Is this a twist-lock receptacle and someone forgot to twist before pulling?

Have you approached the manufacturer of the GPU and brought this up with them?

edit: Roger & I were typing at the same time; he's faster!

 

[petersonra]

I am a General Contractor and have a customer who uses GPU(Ground Power Units) to start turbo prop aircraft in a project I just built. This is a portable device that plugs into a 480V receptacle we provide. The GPU does not have a UL approval and the Electrical Engineer says NEC requires All equipment to have UL approvals to meet code. Is this true?

If the engineer actually said this, he is just wrong. as another poster mentioned there are multiple agencies that list things, not just UL. The code only requires listing of those items it specifically says must be listed. It is possible there is some other requirement that might apply and might require UL listing (such as a customer spec), but it is not in the NEC. My first thought was that it was unlikely that a GPU would be listed at all but it appears at least some are listed to UL 1012.

This issue came up when the plug on the device shorted out because the operator pulled the wires out of the male receptacle. The circuit breaker in the electrical inside 480v panel did not trip but the main outside distribution panel breaker for the 480v service did trip. The engineer said that could happen because it may bne more sensitive. Shouldn't the inside smaller breaker trip before the larger outside breaker trip??
.

It depends on the individual breakers, and maybe even the ambient temperature at each breaker. if the breakers have similar TCC, there is no way to tell with any certainty which one will trip first.

 

[iwire]

The NEC covers building & premises wiring and stops at that receptacle.

I know a lot of people say that but there are many clear examples of the NEC continuing past the outlet.

 

[rbalex]

... My first thought was that it was unlikely that a GPU would be listed at all but it appears at least some are listed to UL 1012.
...

This may be where Fed or State OSHA steps in. (Acceptable State plans must be at least as rigorous as FedOSHA)

See the definitions in 29 CFR 1910.399 for Acceptable, Accepted and Approved.

Essentially, if you parse Acceptable (1), (2) and (3) carefully, a product that can be NRTL certified must be; that is, Acceptable (2) or (3) can only apply when Acceptable (1) doesn't.

 

[usconstruction]

ul approval

ul approval

The NEC covers building & premises wiring and stops at that receptacle. Since your GPU is cord & plug connected, the NEC does not apply to it. However that does not mean some other requirement, such as OSHA or otherwise, applies to that GPU and possibly requires NRTL listing. A common misconception is that things have to be "UL Listed" when in fact there are many Nationally Recognized Testing Laboratories (NRTL's) which are acceptable to provide listing services.

Is this a twist-lock receptacle and someone forgot to twist before pulling? Don't know but the wire was pulled out of male receptacle 1/2 inch

Have you approached the manufacturer of the GPU and brought this up with them? yes they say not required but checking
edit: Roger & I were typing at the same time; he's faster!

see above

 

[usconstruction]

ul approval

ul approval

The NEC doesn't require all equipment to be third party listed but local codes might. The tripping problem sounds like a breaker setting, is the main an electronic breaker and does the service have GFP?

Roger

There is a main breaker also but that is not the one that tripped. it is an 800 amp service that goes into another main panel with 6 sub panels there after. I don't believe it is GFP.

 

[mgookin]

I know a lot of people say that but there are many clear examples of the NEC continuing past the outlet.

Thanks :thumbsup:

 

[jumper]

I know a lot of people say that but there are many clear examples of the NEC continuing past the outlet.

Thanks :thumbsup:

Ditto.