Secondary vs Primary Injection Testing for Circuit Breakers

22 Mar Secondary vs Primary Injection Testing for Circuit Breakers

Products: Low Voltage Circuit Breakers

Cause: Evaluate the difference

Secondary Injection Testing:

• Can only be done on solid-state or electronic trip units with specific portal
• Quick
• Tests trip unit operation only
• Easier
• Takes less expertise to run the test
• Equipment is small and portable
• Different test equipment for different breakers
• Can be used for testing if no changes have occurred in system and breaker has experience no fault

Primary Injection Testing:

• Can be done on any breaker, including thermal magnetic and electronic
• More time intensive
• Tests the complete breaker, including current transformers, contacts, wiring, and trip unit
• Takes years of training and expertise to operate test set
• Equipment is heavy, expensive, and less portable
• Generally required by NFPA after any changes to a system
• Highly recommended for any critical breaker