Cable Insulation Resistance Test Procedure

Perform an insulation resistance test on each conductor with respect to ground and adjacent conductors.

Cable insulation resistance test procedure.

Perform insulation resistance test on each conductor with respect to ground and adjacent conductors. Sample insulation resistance megohmeter test connections for cable and transformer using guard terminal. 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. Locate the connection point of the wire or cable you want to test so you have access to the exposed conductors.

Inspect cables and conductors for proper grounding cable support and termination. The insulation resistance test is the second test required by the electrical safety testing standards. Insulation resistance decreases in temperature or moisture. Insulation resistance testing is a non destructive test procedure.

The megger insulation tester is a small portable instrument that gives you a direct reading of insulation resistance in ohms or megohms. Either turn off the breaker or if you re testing the wiring in a piece of equipment unplug it. Let s clarify our use of the term current. If no literature from the manufacturer is available apply 500 volts dc for 300 volt rated cable and 1000 volts dc for 600 volt rated cable.

Applied potential shall be 500 volts dc for 300 volt rated cable and 1000 volts dc for 600 volt rated cable. It is commonly used in the industry for acceptance testing prior to energizing the cable and for maintenance testing programs. General testing information for single conductor non shielded cable on a reel insulation resistance testing cannot be. Test duration shall be one minute.

Replace or repair sections that exhibit damage. The insulation resistance of cable is measured using a megohmmeter. This is a simple nondestructive method of determining the condition of the cable insulation to check for contamination due to moisture dirt or carbonization. The test measures the insu lation resistance between the phases and or between phase and ground.

Inspect exposed sections of cables and conductors for physical damage. When performing insulation tests on conductors and cable apply the following procedure. 7 3 2 2 2 2009. What is insulation resistance testing.

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. Test period must be for 1 minute using a voltage according to manufacturer s published data. The insulation resistance test consists in measuring the insulation resistance of a device under test while phase and neutral are short circuited together. This test is used to detect conductor insulation damage that may have been caused during installation.