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#112283 - 05/15/01 05:50 PM Hot Box!!
Webmaster Offline


Registered: 10/07/00
Posts: 3169
Loc: NY, USA
Being an inspector for an engineering firm is a bit different than
working for a State, or County. The contractor knows after the first few "encounters" what you will expect. At Dulles, we expect them to READ their specs, and KNOW their code. They also know we will be there all day, every day. It is best to ask the question prior to beginning work, and we are always available for the consultation. A contractor was to provide temporary power for a major rebuild (I'd rather not say what as that pinpoints the project and contractor). I was not paying a lot of attention as Conex boxes came in, but being nosy, a few days later, I opened a conex box to find what you see in the pictures.

Submitted by George Corron
This is what they had done (and spent a LOT of money to really mess up some good equipment)

1. Taken the coils out of an old 13.2/480 transformer and bolted them to the floor of the conex box. 2500 kva (big fella), access was through a 2' bolted panel, or through the 15 kv switch. Violation 110-3, 450-13 NEC, 110-16 (96 code)

Transformer Coils

Click on Photo for a closer look

2. Removed the back panel off the 15 kv switch and used it as the front wall of the transformer. Violation 110-3, 90-7

3. The conex also included a 480 volt MDP. Top removed, rear removed, buss bars rearranged to fit the design. Condition 2 with just 3' clearance provided at front. Violation 110-3, 110-16.



Click on Photo for a closer look

Of course, not considering the violations alone, a CONEX box ?? Do you know how HOT they get in the summer sun ? Think that might affect the equipment? I have not found stats on the temps, but you better believe I will take some measurements of my own this summer, just for reference. Square D, and UL might be a bit ticked that they butchered the equipment like this,

don't ya think ??
George Corron

[This message has been edited by Webmaster (edited 05-15-2001).]

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#112284 - 05/15/01 06:12 PM Re: Hot Box!!

Perhaps the conex box is a listed enclosure?
If the doors will swing open, you have your working clearance. Everything inside is within the enclosure. Your arms are just too short.

As for temperature, you wouldn't mind if they leave the doors open this summer, would you? The transformer runs cooler without the factory case around it, you know.

Perhaps you can bust them for not having two ground rods.

#112285 - 05/16/01 03:02 AM Re: Hot Box!!
sparky Offline

Registered: 10/18/00
Posts: 5545
i wonder if a NRTL would list it as an assembly?

#112286 - 05/16/01 04:23 AM Re: Hot Box!!
electure Offline


Registered: 12/24/00
Posts: 4229
Loc: Fullerton, CA USA
It just needs some wheels and a long cord to perfect the design.

#112287 - 05/22/01 07:29 PM Re: Hot Box!!
George Corron Offline

Registered: 05/16/01
Posts: 728
Loc: Lorton, Va USA
Happy ending. They replaced the equipment, had the USED equipment tested by a NRTL (met) and all is well, danged I don't get to measure the temp of the transformer as it bursts into flames. One of the guys from the electrical contractor said we did it wrong, considering where we are, we should have put wings on it, push it down the runway and see if it flies.

#112288 - 05/23/01 07:10 AM Re: Hot Box!!
WARREN1 Offline

Registered: 05/09/01
Posts: 184
Loc: Greenville, SC, USA
Obviously, shop drawings were not submitted and approved by the specifying engineer, and if they were, the contractor tried to pull a fast one. Good job on this catch.


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