Schluter Megohmmeter

The insulation resistance test is intended to detect very small breaks throughout the cable insulation before, during, and after installation. These breaks often remain undetected during the continuity test since they are not necessarily short circuits between the conductor and the ground braid. Even though they are small, these breaks can cause a current leakage to ground. Such a leakage is usually detected by the mandatory ground-fault circuit interrupter "GFCI" (thermostat with integrated GFCI or panel mount GFCI). When a current leakage is detected, the GFCI trips the circuit, thus disabling the floor heating system. A megohmmeter (sometimes referred to as a "megger") is a special type of ohmmeter, which supplies high voltage to measure the electrical resistance of insulators. An ordinary ohmmeter or multi-meter is not capable of producing the required voltage and therefore cannot be used to perform this test.