Eristävyysmittauksia

Eristävyysmittauksia, often translated as insulation resistance testing or megger testing, are essential procedures in electrical maintenance and safety. These tests are performed to assess the integrity of electrical insulation in various equipment, including cables, transformers, motors, and switchgear. The primary goal is to ensure that the insulation is functioning correctly, preventing unwanted electrical current from flowing to ground or between conductive parts.

The process typically involves applying a high DC voltage to the insulation for a specific duration. A specialized instrument called a megohmmeter (often referred to by the brand name "Megger") is used to measure the resistance. A high resistance value indicates good insulation, meaning the insulation is effectively preventing current leakage. Conversely, a low resistance reading suggests that the insulation is degraded, potentially due to moisture, contamination, age, or physical damage, and poses a risk of electrical faults, short circuits, or even fire.

The specific voltage applied and the acceptable resistance values vary depending on the type of equipment being tested, its voltage rating, and relevant industry standards. Regular insulation resistance testing is a proactive measure that helps identify potential problems before they lead to equipment failure or hazardous situations. This preventative maintenance can save significant costs associated with unplanned downtime and repairs.