Insulation Resistance Test Procedure

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Insulation resistance test procedure.

230v to measure insulation resistance in ohm s. Performing time resistance tests on large switchgear transformers bushings motors and cables especially at higher voltages require high insulation resistance ranges and clean consistent test voltages. With a little record keeping and common sense however you can get a good picture of the insulation condition from values that are only relative. Insulation resistance testing is a non destructive test procedure.

Set the voltage level of the insulation resistance tester to 500v. Good insulation shows this charge effect over a time period much longer than the time required to charge the capacitance of the insulation. For low voltage installations i e. The insulation resistance test consists in measuring the insulation resistance of a.

Energize the megger for 1 minute. The insulation resistance test is an electrical test which uses a certain type and level of voltage 500v d c. Check full load amps flas with the appropriate meter when the motor is turned on or with a full preference. Check the motor frame earth from phase to phase u to e v to e w to e.

The minimum test value of motor insulation resistance is 1 meg ohm 1 mh. When performing insulation resistance testing you must maintain consistency. Whether the dielectric is good or bad to evaluate a number of test results on the same piece of equipment you have to conduct the test the same way and under the. The megger insulation tester is a small portable instrument that gives you a direct reading of insulation resistance in ohms or megohms.

Continue with this testing procedure. In other cases tests will detect a more serious issue in the moment when current. Developed early in the 20th century the insulation resistance ir test is the oldest and most widely used test for assessing the quality of insulation. The insulation resistance test is the second test required by the electrical safety testing standards.

Since 80 of electrical maintenance and testing. The measured resistance indicates the condition of the insulation between two conductive parts. Insulation resistance decreases in temperature or moisture. Read the value of the resistance at the end of the minute test and note it in your table.

The test measures the insu lation resistance between the phases and or between phase and ground. Because electrical insulation will exhibit dynamic behavior during the course of your test. Using insulation testing with an instrument such as the fluke 1555 10 kv insulation tester combined with fluke connect technology such leaks can be detected as insulation resistance slowly tapers over time a sign of normal and expected deterioration.