Cable Insulation Resistance Test Standard

The megger insulation tester is a small portable instrument that gives you a direct reading of insulation resistance in ohms or megohms.

Cable insulation resistance test standard.

Insulation resistance decreases in temperature or moisture. Principle of insulation testing and influencing factors insulation resistance measurement is based on ohm s law. The insulation resistance test consists in measuring the insulation resistance of a device under test while phase and neutral are short circuited together. Insulation resistance testing is a non destructive test procedure.

Historically many field electricians use the somewhat arbitrary standard of 1 megohm per kv. 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. 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. Since 80 of electrical maintenance and testing.

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. Insulation resistance test. 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 1989 revised editions of the acceptance testing specifications have been published in 1991 1995 1999 2003 and 2007.

On february 19 2009 the american national standards institute approved the neta acceptance testing. Ieee400 1 2007 ieee guide for field testing of laminated dielectric shielded power cable systems. It is commonly used in the industry for acceptance testing prior to energizing the cable and for maintenance testing programs. The test measures the insu lation resistance between the phases and or between phase and ground.

Hands down without a doubt one of the most universally searched topics on ec m s website from a historical perspective is insulation resistance testing as a result some of our most popular evergreen articles like understanding insulation resistance testing continue to top the charts when it comes to most popular content. Cables for rated voltages of 1 kv um 1 2 kv and 3 kv um 3 6 kv reference number. The insulation resistance test is the second test required by the electrical safety testing standards. The measured resistance has to be higher than the indicated limit from the international standards.

The document uses the standard numbering system of ansi and ieee. 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. The international electrical testing association neta specification maintenance testing specifications for electrical power distribution equipment and.