Coil Current Measurement and Analysis – AIS

During coil current measurement, the current signature curve of the command coils is being recorded during breaker operation. Deviations detect potential mechanical and/or electrical problems in the trip or close control components in order to prevent their emergence as actual faults well in advance, and extract information about lubrication and latch operation. This measurement can be performed online or offline. The quality of the control voltage supply is also detectable from these tests. Ideally, this diagnostic is performed during a "First Trip" test, when the breaker is in-service, has not been operated for a long time, and thus lubrication problems will be best to identify. In order to analyze and interpret the measurement result, the coil current trace is being compared to previous coil current traces.