DRM (Dynamic Resistance Measurement)
The built-in micro ohmmeter can also be used for the DRM. The DRM test is performed by injecting a current through the breaker contact and simultaneously monitoring the voltage drop across the breaker contact as well as the current flow during the operation of the breaker. The DRM test requires the circuit breaker analyzer with a high-resolution measurement. The resistance curve, as a function of a contact travel can be used to reveal potential problems related to the arcing contact condition. The injected current value should be as high as possible but not less than 100A to provide a reliable voltage drop reading, thus allowing an easier detection of the arcing contact. This model provides up to 200A.