Purpose:

Insulation resistance testing is a non-destructive test procedure. The test measures the insulation resistance between the phases and/or between phase and ground. 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 performed due to the fact that low voltage single conductors do not have a grounding conductor, shield or ground plane.
• For other cable on a reel, insulation resistance testing can be performed provided the sealing caps are removed. The procedure to test these cables is outlined below.
• NOTE: It is important to remove sealing caps from both ends of the cable to be tested. Residue inside the sealing cap can be conductive and lead to false readings.