Line/load conductors adjacent to one another

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SMB

SMB

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North Charleston, SC
I have an MDP where the line conductors enter from U/G in conduit and connect to the bus in the main compartment of the MDP. Cabinets connected to the MDP have branch breakers feeding loads. Many of these load conductors go back into the main compartment into conduits adjacent to the incoming line conductors and conduits. An electrician is telling me this is a code violation. Any thoughts?

Thanks for all replies.

BTW, they are all the same voltage...480VAC.
 
Feeder line and load conductors can be in the same enclosure or raceway.

Service conductors and feeders cannot be in the same raceway but they can be in the same enclosure.
 
While not a code violation - it may be a POCO thing specific to your area - sometimes they have limitations on what can be in the POS enclosure.
 
Also - a 'sealed' enclosure - may not be looked at as 'accessible'... The service sections like CT cab, or 'point of service' termination are usually sealed by the POCO.
 
Let me add more description: The incoming service conductors are from the secondary of a pad mounted transformer with no secondary OCPD....a typical power company install. The load cables come from other sections of the MDP and are installed in conduits adjacent to the service feeders in the same enclosure. The electrician seems to think this is a serious code violation. The code does mention for switchboards conductors shall be routed to minimize inductance. I will try to up load a picture.
 
The electrician could be thinking of 230.7, which disallows conductors other than service conductors being installed in the same raceway or cable.

Or, more likely, as Pete showed, 408.3(3) will keep you from installing branch or feeder conductors in the manner described, they may only pass through a vertical section horizontally if not terminated in that section. Not from one section to another and then turning up or down.
 
Volta said:
The electrician could be thinking of 230.7, which disallows conductors other than service conductors being installed in the same raceway or cable.

Or, more likely, as Pete showed, 408.3(3) will keep you from installing branch or feeder conductors in the manner described, they may only pass through a vertical section horizontally if not terminated in that section. Not from one section to another and then turning up or down.
Click to expand...

408.3(3) exception: allows horizontal travel where conductors are isolated from busbars

by barriers.
 
Volta said:
Yeah, horizontal. That means they cannot exit or enter from above or below.
Click to expand...


I don't see it that way. 408.3(3) is the rule, it says only conductors intended for termination in a vertical section shall be located in that section.

the exception to the rule is, conductors may pass horizontally through vertical sections
where isolated from busbars with barriers.

I don't see 'above or below' anywhere, plus, where else would the conductors be going ?
 
benaround said:
...
I don't see 'above or below' anywhere, plus, where else would the conductors be going ?
Click to expand...

SMB said:
I have an MDP where the line conductors enter from U/G in conduit and connect to the bus in the main compartment of the MDP. Cabinets connected to the MDP have branch breakers feeding loads. Many of these load conductors go back into the main compartment into conduits adjacent to the incoming line conductors and conduits. An electrician is telling me this is a code violation. Any thoughts?
....
Click to expand...

Into conduits adjacent to the incoming. That would be vertical. Unless 'adjectant' in this use means on a wall adjacent to the bottom. Could be.
 
1. If feeder or branch-circuit conductors come from load sections into the service section horizontally and turn to exit the enclosure vertically, I say violation.

2. If feeder or branch-circuit conductors come from load sections into the service section horizontally and turn to exit the enclosure horizontally, and there is a barrier to isolate them from the busbars, I say it meets 408.3(A)(3), Exception, and is ok.
 
Well what do you think 408.3(A)(3) allows? Do you think those conductors from other sections can travel vertically through the service section?
 
Good comments all around. However, I agree with "benaround". As written, 408.3(3) allows for horizontal travel if protected from the bus by a "barrier". What is a "barrier"...not defined in the NEC? Another PE told me the 600V insulation on a conductor is a "barrier" so the conductor can touch the bus. I disagree with that and think if it was installed in a neat manner and with any fore-thought, there would be no conductors on or near the bus.
 
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