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Is Primary Injection testing necessary when changing a Micrologic trip unit?

Why do PI testing when replacing a Micrologic trip unit?

Product Line:
Circuit Breakers

Powerpact P, R and Masterpact breakers

Primary injection testing is required per instructions but it does not need to be a full battery of PI tests.  It is acceptable to inject current on each phase and verify it is metering correctly; this verifies metering chain and that performer plug is connected correctly.  
Also verify through the display that Ir is correct (turn Ir dial with screwdriver and ensure the display matches the sensor size when set on 1); this verifies sensor plug and long time rating plug are connected correctly. Then trip the breaker (one phase) - this can be done with GF test if it is a 6.0 trip unit. If not turn all settings to minimum and cause trip. This verifies trip solenoid is connected to trip unit.
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