Motor Insulation Resistance Test Iec Standard

As a production test this test is often used as a customer acceptance test with minimum insulation resistance per unit length often specified by the customer.

Motor insulation resistance test iec standard.

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. Figure 3 typical scale on the megger insulation tester. The measurement of insulation resistance is a common routine test performed on all types of electrical wires and cables. The measurement of insulation resistance is carried out by means of a megohmmeter high resistance range ohmmeter this is how the test works.

One meg ohm rule for ir value for equipment. 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. Figure 4 typical record of insulation resistance of a mill motor. The results obtained from ir test are not intended.

Regular checks of motor insulation resistance the key to prolonging the life of any electrical device is periodic checks maintenance the insulation resistance of stored and active motors should be checked regularly. See the site fixed equipment for measurement and testing of electrical networks energy management and optimization systems. 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. 1 magnet wire at high stress in air voids b.

Testing and inspection environmental measurements laboratory instrumentation power and energy. 1k v 1 mω minimum 1kv 1 mω 1kv. As per ie rules 1956. Portable measurement equipment in a wide variety of fields.

Based upon equipment rating. Dc voltage of 500 or 1000 v is applied between the windings and the ground of the motor. At a the insulation resistance decreases due to aging and dust accumulation. During the measurement and immediately afterwards some of the terminals carry dangerous voltages and must not be touched.

Ground insulation test of a motor. 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. The sharp fall at b indicates there was an insulation fault.

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. Curve b shows same values corrected to 20 c see page 22 giving a definite downward trend toward an unsafe condition. 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.