3 phase panel marking(subpanel)

[timpwilliams]

I would like to see if someone could settle a disagreement that my employer and I have been having over landing of conductors in a three phase subpanel, or equipment disconnect. The panel from which these paticular loads have been fed also have single phase loads coming out of them, causing the phasing to come out of the panel: "C" "A" "B" or "B" "C" "A" instead of "A" "B" "C". My argument is that it does not matter how it works out, off the circuit breaker, it still should be put back in the subpanel or disconnect "A" "B" "C" . My Employer says if it comes off the breaker "C" "A" "B", it should go back in the subpanel or disconnect the same way. he cannot give me reason behind his thoery. Any Help would be greatly appreciated.
Thanks
Tim

 

[bennie]

Re: 3 phase panel marking(subpanel)

The only important thing is direction of rotation at the outlets.

This is only important if direction sensitive equipment is portable and moved to different locations.

 

[don_resqcapt19]

Re: 3 phase panel marking(subpanel)

Look at 408.3(E).
Don

 

[bennie]

Re: 3 phase panel marking(subpanel)

It is important on a 4 wire delta. For identifying the high leg or B phase.

A wye is not important.

[ April 09, 2003, 10:53 PM: Message edited by: bennie ]

 

[don_resqcapt19]

Re: 3 phase panel marking(subpanel)

Bennie,
Even if it is not important, it is a code rule.
Don

 

[jgriffin]

Re: 3 phase panel marking(subpanel)

Whatever happened to A,B,C,....From left to right...Front to back ...Top to bottom?

 

[charlie b]

Re: 3 phase panel marking(subpanel)

Originally posted by jgriffin: Whatever happened to A,B,C,....From left to right...Front to back ...Top to bottom?

It's still there. See Don's post of 4/9.

 

[iwire]

Re: 3 phase panel marking(subpanel)

Unless it is Square D I-Line, that is ABC top to bottom and bottom to top at the same time.

 

[don_resqcapt19]

Re: 3 phase panel marking(subpanel)

Bob,
I believe that the I-Line bus is the same, it is just the load side of the breakers that is reversed.
Don

 

[iwire]

Re: 3 phase panel marking(subpanel)

Don, you are correct, (no surprise ) it would be the right-hand side load terminals, if the panel is set up for right-hand side breakers, some are not, and I know that 408.3(E) is specifically about bus bars.

But it looks kind of strange when you cut it in and Brown is opposite Yellow.

Small trade off for a great panel though.

 

[iwire]

Re: 3 phase panel marking(subpanel)

Originally posted by timpwilliams:
The panel from which these particular loads have been fed also have single phase loads coming out of them, causing the phasing to come out of the panel: "C" "A" "B" or "B" "C" "A" instead of "A" "B" "C".

You could just move the breaker down and leave one or two bus spaces as spares then it comes out of the breaker ABC top to bottom, but as Bennie said how it leaves the breaker is not important, it is how you land it at the other end.

A to A, B to B, and C to C left to right or top to bottom or rarely front to back.

Bob

 

[roger]

Re: 3 phase panel marking(subpanel)

Remember that if we relate ABC to 123 in many situations there must be a change somewhere in the chain for rotation purposes as Bennie pointed out.

I have always prefered to see the same configuration from breaker to line side of any disconnect just as Bob described. On the load side of the disconnect I would make my change.

This is just my preference. I have swapped conductors at any point in the past and will again.

Roger

 

[spyder]

Re: 3 phase panel marking(subpanel)

Whether its required or not, why not keep it consitent. It will avoid problems and be easier to troubleshoot later.

 

[ledolectric]

Re: 3 phase panel marking(subpanel)

Originally posted by spyder:
Whether its required or not, why not keep it consitent. It will avoid problems and be easier to troubleshoot later.

I totally agree,where practical I'd adhere to the"a-b-c" system.

 

[timpwilliams]

Re: 3 phase panel marking(subpanel)

Thanks for everyones help and input, maybe now this is something that can be put to rest
Thanks again
Tim