Insulation resistance tester, commonly known as "megohmmeter" or "megger", is a precision instrument specifically used to measure the insulation resistance of electrical equipment, cables, motors, and transformers.



Its core function is not to measure conductor continuity, but to evaluate the quality of insulating materials. By applying high-voltage DC to the tested object and detecting its "leakage current", it determines whether the equipment is damp, aged, or at risk of breakdown. It serves as the "health check doctor" ensuring the safe operation of power systems.