Temporary loss of supply

[magneticted]

In your opinion under the following condtions would large motors 300 kw to 4000 kw be able to copewith the following

"Motors shall be capable of recovering normal operation in the event of a system disturbance causing temporary loss of supply voltage of periodfs of upto 0.2 seconds ( fault clearance time ) followed by a sudden restoration, intially to 60% rated voltage for 3 seconds, then followed by a sudden restoration to 80% voltage, from which voltage the motors shall then be capable of accelerating and ulitmate recovery under the most arduous conditions. )Pump full load, open discharge )"

Your thoughs would be welcome, thanks

 

[spargher]

It depends from the electromechanical design.

Motor designer should calculate the torque-speed characteristics based on the pump torque-speed curve in order to have a motor capable of doing it

You can calculate the motor speed after the 0.2 seconds failure, and so you also know motor torque capability (at the specified voltage). If the load torque demand is higher than motor capability, the motor will not recover the full speed.

 

[LionelHutz]

A typical motor and centrifugal pump would be capable of approximately 70% speed when at 60% voltage and would be close to full speed at 80% voltage. You should confirm this with your motor manufacturer.

 

[treborrenrut]

Help needed! I am trying to find a manual for a Fenner soft start unit Type 534C3010A probably aboput ten years old can anyone help?

 

[jraef]

You need to start a new thread, not tag onto someone elses.

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