H.T. MOTORS (3.3 kV to 11 kV and >250 kW)
RECOMMENDED TESTS AS PER IEC
Tests on Stator
1. Power quality
Voltage level test(Over voltage/under voltage),Voltage unbalance(Examines the single-phase voltage in the motor by calculating its percentage unbalance via NEMA derating,Compares the voltage unbalance level with the stored threshold),Harmonic Distortion( Total Harmonic Distortion & Total Distortion-deal with quantifying the effect of non-fundamental components to the voltage and current waveform),Power.
2. Machine Performance
Effective Service Factor(Identifies thermal overloading of the machine),Load, Operating condition, Efficiency, Payback period(This test searches the database for motors, and compares the energy expenses of the motor under test with higher efficiency motors. Payback period is calculated, based on the compared motor’s list price, the energy savings calculated according to the specified duty cycle of the motor, the entered Rs/kWh, and the latest calculated input power of the motor. This test uses the premise that the comparison motor operates, on average, on a load point similar to the one measured.)
3. Current :Overcurrent, Current unbalance.
4. Rotor bar/Operating condition.
5. V/I spectrum.
6. Connection Domain Analysis.