Circuit Breaker Sizing for 30 KW Motor 1

[tahirinst]

I need to install circuit breaker on 3 Phase Motor ( 30 KW). This motor is installed at Screw air compressor ( direct coupled). Motor voltage 400VAC, 50 Hz

Please advise size of breaker which should be installed. Motor Name Plate data is attached.

 

[waross]

In North America that is a matter of code compliance.
We reach for the Electrical Code book.
For DOL starting of a squirrel cage induction motor the code maximum is 250% of rated current with exceptions.
Consult your local code.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[JuanBC]

Hi tahirinst,

Are you sizing the CB that feeds the Air Compressor's Panel Board or the CB that will directly feed the motor?

Maybe a single line diagram will help us understand your requeriments

Regards.

JBC
.......
"The more I read, the more I acquire, the more certain I am that I know nothing"

 

[tahirinst]

CB will directly feed the three phase motor.....

 

[JuanBC]

Tah: If you are not using a contactor+relay scheme, you should use a "Motor Circuit Breaker" that has Thermal+Magnetic protection

You can just select it from a catalogue (i attach an example)

BEWARE: The rated Volts/frecuency/kA Icu must be in accordance with your installation

JBC
.......
"The more I read, the more I acquire, the more certain I am that I know nothing"