277V Single Pole Breaker in 480Y/277 system

[ajb5102]

Still learning...

I can use a 277V rated single pole breaker in a panel rated for a 480Y/277 voltage, because the single pole breaker will be connected to 1 leg of the transformer secondary side and will see less than 277V? Correct?

 

[augie47]

It certainly can be but I don't know why it would see less than 277v.

 

[Jraef]

It will see 277V, not "less than"...

If your question is about using "slash" rated breakers as opposed to "straight" 480V rated breakers, if you have a 480/277V system, that is exactly what slash rated breakers are for. So no problem.

 

[roger]

It will see 277V, not "less than"...

If your question is about using "slash" rated breakers as opposed to "straight" 480V rated breakers, if you have a 480/277V system, that is exactly what slash rated breakers are for. So no problem.

I want to know why there are slash rated verses straight rated breakers anyways. Why not make one version to cover both scenarios?

 

[hillbilly1]

I want to know why there are slash rated verses straight rated breakers anyways. Why not make one version to cover both scenarios?

$$$$$!

 

[Another C10]

and will see less than 277V? Correct?

At peak hours that 277v may very well drop down to 5-10 volts less, then back up when the off peak usages periods start. The 277v as any other utility supplied voltage fluctuating slightly or at times dramatically during the course of a 24 hour period.

 

[jim dungar]

I want to know why there are slash rated verses straight rated breakers anyways. Why not make one version to cover both scenarios?

They do. The non-slash rated can be used everywhere.