An Insulation Resistance test set far exceeds the capabilities of standard ohm meters. They both test for the insulation properties of electrical wiring, circuit breakers, transformers, and switchgear. However, Insulation Resistance test sets use a much higher voltage to identify resistances. Insulation Resistance tests are non-destructive to the equipment being tested. The test however, can be an indication of a problem. Insulation Resistance voltage settings range from 300V to 10kV. S.E.S.’s team of Field Engineers and Technicians refer to NETA, IEEE, and equipment manufacturer specifications for appropriate test voltages. Insulation Resistance (Megger) testing is often the first step towards identifying breakdowns in transformers, medium voltage conductors (cables), circuit breakers, and other substation equipment including switch boards or switch gear.