The arcing contacts are the most important part of high voltage circuit breaker. Life span of circuit breaker is defined by number of standard operations that arcing contacts are capable to withstand under rated short circuit current. Circuit breaker with worn arcing contacts is unreliable. Therefore, it is very important to assess the condition of the arcing contacts during circuit breaker maintenance intervals. The only effective way to assess arcing contacts condition without dismantling breaking chamber is Dynamic Resistance Measurement (DRM).
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