Cable Insulation Resistance Test Standard

11 ieee 400 2012 omnibus ieee guide for field testing and evaluation of the insulation of shielded power cable systems rated 5 kv and above.

Cable insulation resistance test standard. The test measures the insu lation resistance between the phases and or between phase and ground. Ieee400 1 2007 ieee guide for field testing of laminated dielectric shielded power cable systems. The document uses the standard numbering system of ansi and ieee. The insulation resistance test is the second test required by the electrical safety testing standards.

Insulation resistance testing is a non destructive test procedure. Also acceptable values of insulation resistance depend upon the equipment you re testing. The insulation resistance test consists in measuring the insulation resistance of a device under test while phase and neutral are short circuited together. 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.

After dc overpotential test is completed the insulation resistance test is done again to assure that the cable has not been damaged by the hi pot. When overpotential testing cable its common practice to conduct the insulation resistance measurement first and then proceed with the dc overpotential test if acceptable readings are achieved. Since 80 of electrical maintenance and testing. The international electrical testing association neta specification maintenance testing specifications for electrical power distribution equipment and.

Regular testing of the insulation on an installation or machine is therefore a useful way of monitoring this type of deterioration so you can act before total failure occurs. The megger insulation tester is a small portable instrument that gives you a direct reading of insulation resistance in ohms or megohms. It is commonly used in the industry for acceptance testing prior to energizing the cable and for maintenance testing programs. Historically many field electricians use the somewhat arbitrary standard of 1 megohm per kv.

The measured resistance has to be higher than the indicated limit from the international standards. 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 purpose. Principle of insulation testing and influencing factors insulation resistance measurement is based on ohm s law.

Insulation resistance test. Cables for rated voltages of 1 kv um 1 2 kv and 3 kv um 3 6 kv reference number. On february 19 2009 the american national standards institute approved the neta acceptance testing.