Does Schneider Electric recommend primary injection or secondary injection testing for LV circuit breakers?

Issue:
What are the considerations for primary vs. secondary injection testing?

Environment:
All MCCBs

Resolution:
Both primary and secondary injection testing have their place in maintenance testing of MCCBs.  In general, secondary injection is preferred for routine testing because it places less stress on the circuit breaker, involves less risk, and is faster and less expensive. There are times, however, when primary injection is preferred.  Review the attached document to obtain a better understanding of what each test method involves and which is recommended for specific cases.

Released for: Schneider Electric USA