Thought I seen it all...

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captainwireman

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This is in a utility combined cycle powerhouse. I know technically the code does not apply. Here is the situation. 4 4" RMC feeding switchgear. The section is not wide enough to accept the conduit with the spacing so in their infinite wisdom, the powers that be stopped the run approximately 5' from the top with grounding bushings on the ends of the conduit, ran the paralleled feeders (xhhw-2) exposed to 3" nipples 10" tall that did fit in the section. The 3" would not be overfilled supposedly because of the nipple fill calculation (gasp!). Besides workman like manner, what specific codes could I cite to condemn this application?
 
If there is a piece of cable tray between the ends of the conduit and the nipples, I see nothing to condem.
My concern would be the movement of the conductors during a fault.
 
Is this a theoretical question?

I believe the generation utility not covered by the NEC may be under the NESC. However, if you are not authorized to enforce the NESC, it doesn't even matter if there is a violation of that code.

I worked inside power houses for years. For the most part, they were electrically sound and fit. But we were constantly reminded that the NEC did not apply there and not to be surprised if we saw 'code violations'.

I don't know what your business is at the power plant. I see 'inspector' along with electrician in your profile. IIRC, electrical inspectors weren't even allowed in the power plants I was in. As electricians working for outside contractors, we were told to MYOB when it came to what the POCO did inside their plants. So long as it was safe, that was good enough.

If the powers that be have allowed the installation, there isn't much to do to stop it. About the only thing I could think of would be to seek out the EE that is in charge of the project. He may not know about it and may stop it right there. If not, oh well....
 
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You nailed it The NEC does not apply to power plants. Would the NESC apply here ?

As long as the powers that be approved this installation it must be OK. We know in your mind

that it looks like hack work, but that is your opinion not the POCO.
 
John120/240 said:
You nailed it The NEC does not apply to power plants. Would the NESC apply here ?

As long as the powers that be approved this installation it must be OK. We know in your mind

that it looks like hack work, but that is your opinion not the POCO.
Click to expand...

I agree with John 100%
 
You nailed it The NEC does not apply to power plants. Would the NESC apply here ?

As long as the powers that be approved this installation it must be OK. We know in your mind

that it looks like hack work, but that is your opinion not the POCO.
Click to expand...

I agree with John 100%
Click to expand...

That being said, I have worked in several of the area's power plants, operated by Consumers Energy. Anything there that looked like hack work was temporary. Sometimes long temporary, like nearly two years, but eventually a shut down was scheduled to tear out temp hook up and make it up correctly. Everything we did that was meant to stay was usually built in excess of NEC requirements.For instance , I saw a 2400 volt back feed connected with HV 'jumper cables' from about 80' above ground to a terminal shack at ground level. This was outside and visible from the highway. Three huge 5kV cables with clamps, no raceways. Almost two years to the day, they scheduled a shut down for us to fix it. We had to tear out tons of underground lead cable in addition to rebuilding the bus run down the side of the building. Even the torque on the bolts was double checked by a QC rep and notes taken thereof.

On Wednesday, the side of the building looked like hell. By Monday everything was new. Yeah, that's right. Weekend pay, 4 12's, ca-ching!!!

But my point is unless you are a POCO employee, you may not know the entire story and the 'problem' may be scheduled to be changed out a few months from now, or shut down and torn out altogether.
 
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John120/240 said:
.... Would the NESC apply here ?

...
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NESC can be applied, same as the NEC, but it is not required. I have been on a couple power plant projects where the construction spec's required installation per NEC. Have not seen any that said to NESC.

The OP may be QC/QA on a project spec'd to NEC standards...
 
jim dungar said:
If there is a piece of cable tray between the ends of the conduit and the nipples, I see nothing to condem.
My concern would be the movement of the conductors during a fault.
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Exposed XHHW-2 is not a cable tray wiring method listed in Table 392.10(A)...???

Edit: Unless it is also marked as Type TC.
 
Smart $ said:
Edit: Unless it is also marked as Type TC.
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Which maybe the case.
"Southwire Type XHHW-2 copper conductors are also available in sizes 1/0 AWG and larger rated for cable tray use and sunlight resistant".

Insulation with a 'Cable Tray' rating is not necessarily the same as stuff that is manufactured specifically using 'Tray Cable' construction.
 
All you have said here is true. I am not the AHJ, just a concerned journeyman on this project seeking knowledge. There is no cable tray. Of course they can do what they want but this was meant as a permanent installation. I would like to inform my apprentice and fellow journeymen on code specifics related to this installation. Thanks to all and I welcome any brainstorming.
 
How are the individual conductors secured between the conduit and connector?

Doesn't the NESC have a minimum requirement for securing conductors where they enter a box conduit or connector?
 
captainwireman said:
I would like to inform my apprentice and fellow journeymen on code specifics related to this installation.
Click to expand...

That sounds good, but may I suggest instead of presenting it as 'A dangerous installation that should be changed to the comply with the NEC' I would present it as simply 'A different way of doing things and point out how it would be done under the NEC.'

My own view is it is not helpful to present the NEC as the end all, be all, electrical code.

Point out that there are other codes that different from the NEC but also get the job done.

For instance in many countries they use a lot more exposed flexible cord wiring methods, something that the NEC generally prohibits but it works fine in those countries.
 
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