Phasing a Tie Circuit Breaker

[Larry5443]

When phasing a tie breaker and you have 0 volts on A phase and 0 volts on B phase and 480 volts on C phase what is the right way to phase this .Do you roll the high side or the low side or both and what phases do you roll .Or do you roll phases on both low side or high side of each transformer.

[ruel guanzon]

When phasing a tie breaker and you have 0 volts on A phase and 0 volts on B phase and 480 volts on C phase what is the right way to phase this .Do you roll the high side or the low side or both and what phases do you roll .Or do you roll phases on both low side or high side of each transformer.

roll the high side and roll phase B and C?.

[ruel guanzon]

roll the high side and roll phase B and C?.

Hi Larry! did I get this one right?

[Larry5441]

Hi Larry! did I get this one right?

No you did not what did you use for a reference ,you guessed lol sorry

[madMAX]

When phasing a tie breaker and you have 0 volts on A phase and 0 volts on B phase and 480 volts on C phase what is the right way to phase this .Do you roll the high side or the low side or both and what phases do you roll .Or do you roll phases on both low side or high side of each transformer.

Roll B and C on the load side? I don't think rolling the high side would result in 0 volts on the secondary, it would probably be like 340 or something.

[drrios1]

Hello Larry
I'm confused.
I have never had my readings like you said. I may have one phase is 0 and the other 2 read 480.
But I have never seen 2 correct and 1 incorrect.
Please elaborate or give me some more help.
The only thing I can think of is rotation but I still believe only 1 would be correct and 2 incorrect
Thanks for sharing this is making me think about how much I haven't seen

[jl8200]

You cant have a single roll on a 3 phase system. 2 phases would be reading voltage and one would read zero. This isn't possible because you have to swap two phases if phasing isn't correct. Maybe im not understanding the question...

Hello Larry
I'm confused.
I have never had my readings like you said. I may have one phase is 0 and the other 2 read 480.
But I have never seen 2 correct and 1 incorrect.
Please elaborate or give me some more help.
The only thing I can think of is rotation but I still believe only 1 would be correct and 2 incorrect
Thanks for sharing this is making me think about how much I haven't seen

[joaogemal]

There's no answer for this question, not in the way it is posted.

[SecondGen]

I agree. Can we get some clarification on this question Larry?

There's no answer for this question, not in the way it is posted.

[joaogemal]

See the picture.

But, if the question was like:
You read 480 Volts on phase A and B, and Zero Volts on phase C then, the solution will be:
Roll A and B on one side of the breaker.