Code: 480 V versus 575 V
Code: 480 V versus 575 V
(OP)
I am doing a new installation of some switchgear. Our current standard voltage at my facility is 575 V 3 Phase. The design for the motor controls is to have a breaker and not a fused disconnect. I was told that this is against code. My source said that this application is OK for 480 but not 575. Can somebody lead me in some direction of what is right or wrong?





RE: Code: 480 V versus 575 V
David Baird
Sr Controls Designer
EET degree.
Journeyman Electrician.
RE: Code: 480 V versus 575 V
RE: Code: 480 V versus 575 V
I am located in Louisiana.
RE: Code: 480 V versus 575 V
RE: Code: 480 V versus 575 V
Not that it matters, but are you talking about the disconnecting means at the starter or at the motor?
RE: Code: 480 V versus 575 V
I agree with you both. This facility has a majority of fused disconnects and very few breakers for motor protection, so I think they were trying to shoot me a line of BS when they said it was against code. This place is a little old school and stuck in their ways and they just don't anything new. I am talking about the disconnects at the starter. Thanks for your input.
RE: Code: 480 V versus 575 V
RE: Code: 480 V versus 575 V
Yeh, I believe you are correct. Thanks.
RE: Code: 480 V versus 575 V
Eng-Tips: Help for your job, not for your homework Read FAQ731-376
RE: Code: 480 V versus 575 V