Circuit Breaker Operation Time (In-Service) (AIS)
In-service testing methods show degradation accumulated during long idle times better than their off-service counterparts because to prepare a breaker for off-service testing, it has to be operated at least once. For the First trip test method connections are made at the trip coils and the CT’s secondary side. These test methods are very well suited to detected degraded lubricants, contaminated surfaces or corroded mechanical elements.
During a First Trip test, CIBANO measures the opening times by monitoring the CTs’ secondary current (please note that the measured time will include the arcing time).