Isolasjonsmåleren

Isolasjonsmåleren, often referred to as an insulation tester or megohmmeter, is an electrical instrument used to measure the electrical resistance of insulation. This measurement is crucial for determining the integrity and safety of electrical equipment and wiring. High insulation resistance indicates that the insulating material is effectively preventing electrical current from flowing where it shouldn't, which is essential for preventing short circuits, electrical shocks, and equipment failure.

The isolasjonsmåleren typically works by applying a high voltage, often DC, to the insulation being tested and then measuring the resulting current flow. According to Ohm's Law (R = V/I), a higher voltage applied to a given current will result in a higher resistance reading. Common test voltages range from 50 volts to 1000 volts or more, depending on the application and voltage rating of the equipment.

In practice, an isolasjonsmåleren is used in a variety of settings. Electricians use it to test newly installed wiring and electrical systems before energizing them. Maintenance personnel use it to periodically check the condition of motors, transformers, generators, and cables. A gradual decrease in insulation resistance over time can signal the deterioration of the insulating material, prompting preventative maintenance or replacement. Readings are typically expressed in megaohms (MΩ) or gigaohms (GΩ). Regular testing with an isolasjonsmåleren is a fundamental aspect of electrical safety and predictive maintenance.