Shop insulation resistance testers and megohmmeters for evaluating the condition of electrical insulation in motors, wiring, transformers, cables and other electrical equipment.
Insulation testers apply a controlled DC test voltage and measure high resistance values to help identify deteriorated insulation, moisture intrusion, contamination and other conditions that may lead to electrical failure.
Insulation resistance testers, sometimes called megohmmeters or meggers, measure resistance at much higher test voltages than a typical digital multimeter. They are commonly used for preventive maintenance and troubleshooting of motors, generators, transformers, cables and electrical installations.
Important selection factors include available test voltages, maximum insulation-resistance range, accuracy, automatic discharge capability and the electrical safety rating of the instrument.
Higher-voltage insulation testers may be required for medium-voltage equipment or specialized industrial applications, while lower-voltage models are appropriate for many commercial and industrial electrical systems.