An insulation tester is an electrical meter used to determine the condition of the insulation on wire and motor windings. The insulation found on wires, cable, and motor windings serves to protect the wire and keep it separate from other wires.

Portable insulation resistance testers and megohmmeters are designed to help prevent hazards such as electric shock and short-circuits caused when the insulation in electrical devices, parts, and equipment is used in industrial plants, buildings, and other settings degrades over long periods of use.