Motor Requirements for Soft Start

[1HVACr]

Are there any special requirements for motors when using SSRV starters? I have a 40 HP ODP 480V Premium Efficient motor. Thanks

 

[DickDV]

No, unless you need to take more than 3 minutes to accelerate up to speed

 

[1HVACr]

Thanks!

 

[Marke]

Hello 1HVACr

The best soft start performance that you will get is determined to some extent by the motor.
If the motor has a very high locked rotor current and a moderate locked rotor torque, then the minimum start current for a given load will be higher than a motor that has a low locked rotor current and a high locked rotor torque.
This is because the start torque developed by the motor is a function of the full voltage curves reduced by the current reduction squared.

Best regards,

Mark Empson
L M Photonics Ltd