Motor Insulation Resistance Test Iec Standard

Figure 4 typical record of insulation resistance of a mill motor.

Motor insulation resistance test iec standard.

Ground insulation test of a motor. Dc voltage of 500 or 1000 v is applied between the windings and the ground of the motor. The sharp fall at b indicates there was an insulation fault. Based upon equipment rating.

See the site fixed equipment for measurement and testing of electrical networks energy management and optimization systems. 1 magnet wire at high stress in air voids b. During the measurement and immediately afterwards some of the terminals carry dangerous voltages and must not be touched. The intent of the iec standard is to specify test methods that assure a given stator insulation design can prevent formation of pd in new windings and continue to suppress pd throughout the life of the motor type i insulation.

1k v 1 mω minimum 1kv 1 mω 1kv. Curve a shows test values as measured. At a pressure of 1000 v applied between each live conductor and earth for a period of one minute the insulation resistance of hv installations shall be at least 1 mega ohm or as specified by the bureau of indian standards. Portable measurement equipment in a wide variety of fields.

The graph below shows an example of the insulation resistance readings on an electric motor. At c the fault has been repaired rewinding of the motor so the insulation resistance has returned to. Figure 3 typical scale on the megger insulation tester. Reverse side of card at right is used to record the test data.

Power cables with extruded insulation and their accessories for rated voltages from 1 kv um 1 2 kv up to 30 kv um 36 kv part 1. Iec 60034 27 4 2018 provides recommended test procedures for the measurement of insulation resistance and polarization index of stator and rotor winding insulation of rotating electrical machines. Curve b shows same values corrected to 20 c see page 22 giving a definite downward trend toward an unsafe condition. At a the insulation resistance decreases due to aging and dust accumulation.

The results obtained from ir test are not intended. A if the insulation resistance of a new cleaned or repaired motor that has been stored for some time is less then 10 mω the reason might be that the windings are humid and. One meg ohm rule for ir value for equipment. Testing and inspection environmental measurements laboratory instrumentation power and energy.

The measurement of insulation resistance is a common routine test performed on all types of electrical wires and cables. Cables for rated voltages of 1 kv um 1 2 kv and 3 kv um 3 6 kv reference number iec 60502 1 2004 e international standard iec 60502 1 second edition 2004 04. As per ie rules 1956.