Why test circuit breaker

Circuit breaker is one of the most important component in every electric power system. The circuit breaker has to operate within extremely tight tolerances when a disturbance is detected in the network to protect sensitive and costly components such as transformers.

Some of the most important of the many reasons for testing circuit breakers are to ensure they:

• Provide protection for expensive equipment
• Prevent outages that lead to loss of income
• Ensure reliability of the electricity supply
• Prevent downtime and darkness
• Verify breaker performance

Substation breaker testing is an important task for any power utility. The breakers are there to facilitate the flow of current during normal operation and to interrupt current flow in the event of a fault. However, all electrically operated devices are, sooner or later, likely to experience some kind of failure. That failure can be caused by many factors, including ageing and external faults.

Type of Test in Circuit Breaker

▪ First trip test
▪ Contact Timing
▪ Primary injection test
▪ Motion
▪ static resistance measurement (SRM)
▪ dynamic resistance measurement (DRM)
▪ synchronized switching
▪ Coil test
▪ Minimum voltage test
▪ Minimum voltage required to operate breaker
▪ Vibration testing
▪ Vacuum bottle test
▪ Primary testing
▪ Oil test
▪ SF6 leakage
▪ Humidity test
▪ air pressure test