Voltage difference

[john37]

Could someone please tell me what Article states that you can not have two seperate voltages in the same wireway? I have been looking high and low in the NEC and can't find it. Thanks.

 

[e57]

You wont find it - it is not there, and allowed... However see 200.6D about neutral of different system - even of the same voltage - but from different transformers...

Usually people use white for the 120/208/240's and gray for the 277/480.
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Doh! Do you mean like Class 1 and class 2 or 3? Art. 725.26

 

[john37]

Sorry, I should have been more descriptive on my question. I'm working on an old building on a military base and I have this case where there are two services coming into a building. One service is 440V (not 480V) and the other service is 220V (not 208V). Both services are 3 phase. The 440V service is feeding off a pole with 3-50KVA transformers and the 220V is feeding from another pole with 3-45KVA transformers. This is an old building I believe was built in the 60's. Anway, from the poles the feeders go underground into a vault to seperate main disconnects and then from the vault go underground into a wireway located in the main electrical room. From the wireway they branch off to a 440V 400A main fused disconnect and then a 400A 220V distribution panel.
My boss had told me that it is a code violation to have the 440V and 220V feeders in the same wireway with no seperation in the wireway. I went back to the office to try to find what Article states this but haven't been successful. Is this allowable per code? If not, what Article states it.
Thanks.

 

[ptonsparky]

Your boss is the one that told you it is a violation, have him give you the reference.

It is not a violation for the systems to share a raceway. In the 2008 you will find that conductors should be identified in some manner. 210.5(C)

IMO, the NEC is permissive. You are allowed to do something unless prohibited. Trick is finding where the NEC says "No".

 

[jimmac49]

Have a look at Article 300.4 - C - 1 of the 2005 NEC. I think that it answers your question.

Jim

 

[nyerinfl]

Have a look at Article 300.4 - C - 1 of the 2005 NEC. I think that it answers your question.

Jim

That would be 300.3 C (1)

 

[john37]

Thank you guys. Article 300(C)(1) answered my question. It specifically says it's allowable. I didn't think it was a violation that is why I was looking in the code. Now I have to figure out how to explain it to my boss in a "nice" manner....

 

[e57]

You'll also be surprised to know that the DOD never adopted the NEC other than it being a construction standard. (They have their own standards...) You may find other things that would violate the NEC - if it were applicable, and at the time of installation.

Ahhhh... correction they did...... In 82.... When I was on Base Maint in 93/4 I was told they didn't Hmmmmm....