No Load Motor Trial Procedure

Dear Sir,

No Load testing of Motor will be conducted only to know Magnetizing Current of the Motor.

To check the Motor performance like,Heating of body,Bearings,Power Consumption,Power factor Motor has to run on diffrent Loading Conditions staring from 25% to 125%.

During loading condition there should not be rise in temperature of Bearings and Motor body after attaining the saturation level.

Regards

Aruna Kumar

You do not say what type of motor it is but in the old DC days 'series' wound motors were quite common. They were used because of their high torque slow speed characteristics.

It was (still is) dangerous to run these motors on no-load because with nothing to stop them (except bearing and commutator friction) (and residual magnetism of the field coils) they run faster and faster and faster - until (usually) the armature bursts (due to enormous centrifual force). The resultant siezure would instantly transfer the angular momentum to the frame which could rip the motor off it's feet to go rolling away to skittle everything in it's path.

It is an incident that tends not to pass unnoticed.

Routine testing of Motors does include a No Load test

During which you will check Curent, Voltage, Power, Speed and Mechanical Vibration.

You want to find the NO-Load Loss

Standards are ANSI C50.41-2000

NEMA MG1-1998 Rev 1Section 20.16 and IEEE 112

Check latest revs of all.

You will want to load the motor

25%-150%