starter

[Romeo]

what should be the contactor current rating in star delta starter of star, delta, and main contactor.

 

[OZEE]

Depends on the load of the driven motor, doesn't it...

 

[Kidblue]

Hi,

Your question is a little vague, but typically, you can de-rate the contactors and overload by 58% of the full load current.

Regards,

Rob

 

[Geospark]

Hi and welcome to the Forum!

Here is a good explaination of reduced voltage star/delta starting for induction motors and the current derating figures for the contactors.

George

 

[Romeo]

thank you all for your suggestions. the motor is of 20HP