Eristysmittarit

Eristysmittarit, known in English as insulation testers or megohmmeters, are electrical instruments used to measure electrical resistance, specifically the resistance of insulation. They are crucial tools for assessing the integrity of electrical insulation in various applications, from household wiring to industrial machinery and power transmission systems. By applying a high-voltage DC current, typically ranging from 50V to 1000V or even higher for specialized uses, the insulation tester can detect minute leakage currents that would be undetectable with a standard multimeter.

The primary function of an eristysmittari is to identify potential faults such as breakdowns, degradation, or contamination in insulating materials. These faults can lead to electrical shorts, safety hazards, and equipment failure. A low resistance reading indicates a problem with the insulation, signaling the need for repair or replacement. Conversely, a high resistance reading signifies good insulation quality.

Eristysmittarit are commonly used during the installation of new electrical systems to verify that the insulation meets safety standards. They are also employed for routine maintenance checks to monitor the condition of insulation over time and predict potential failures. The results from these tests are often recorded and compared to previous measurements to track insulation degradation trends. Different types of eristysmittarit exist, varying in their voltage output, resistance measurement range, and additional features like continuity testing or capacitance measurement.