Isolasjonsmålere

Isolasjonsmålere, also known as insulation testers or megohmmeters, are specialized electrical instruments used to measure the electrical resistance of insulation. This resistance is a crucial factor in determining the integrity and safety of electrical equipment, wiring, and systems. High insulation resistance indicates that the insulating material is performing well, preventing the leakage of electrical current, which is essential for preventing short circuits, equipment damage, and electric shock hazards. Conversely, low insulation resistance suggests that the insulation is degrading or damaged, potentially due to moisture, heat, age, or physical stress.

Isolasjonsmålere work by applying a high DC voltage to the insulation being tested and measuring the resulting current flow. According to Ohm's Law (R = V/I), a very small current flow under a high voltage will result in a very high resistance reading. The applied test voltages typically range from a few hundred volts to several thousand volts, depending on the type of equipment being tested. Common applications include testing the insulation of electric motors, generators, transformers, cables, and switchgear. Regular insulation testing is a vital part of preventative maintenance programs for electrical systems, helping to identify potential problems before they lead to failures or accidents. The results of these measurements are often recorded over time to track the condition of the insulation and predict its remaining lifespan.