Renamepate A Motor

[bufordwon]

Just wondering if I can get some imput on this, a customer of ours has ten 200 H.P. 1185 RPM,447T Frame, 60 HZ,TEFC Lincoln motors he want to ship over seas to Saudi, he wants us to renameplate these to 380 volts 60 HZ and down grade these to 150 HP. I thought Saudi had 50 HZ over there. Our feeling is that they would lose alot of torque. In anyone's opinon, would this work? I would appreciate any help at all. Thanks

 

[teco]

bufordwon:- please advise original volts and insulation class. we understand saudi is 460 volts 60 hz, have your customer check os no change will be required.
kind regds

 

[rhatcher]

Torque in an induction motor is proportional to the ratio of volts per hertz (V/Hz). If you reduce the voltage by 20%, then the torque output will be reduced by the same value. Derating the motor to 150hp would more than compensate for this.

However, I would definitely confirm the voltage and frequency as 380V/60hz sounds unusual.

 

[jbartos]

Suggestion: It may be worthwhile to trade it for a proper one. The motor derating impacts power factor and efficiency, which over 20years can result in noticeable amount of waste. Also, the voltage and frequency shall be verified per the specific location of the motor application since nowadays ac-ac converters are more frequently used in various Countries since they are more affordable.