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Masterpact ground fault breaker connected to modified differential ground-fault (MDGF) system is failing secondary injection test with the full-function test kit (FFTK).

Issue:
Ground Fault Test is failing using FFTK
 
Product Line:
Air Circuit Breaker 
 
Environment:
Masterpact NW with LSIG trip unit
 
Resolution:
The full function test kit will only test residual equipment ground-fault protection. Breakers configured for Modified Differential Ground Fault (MDGF) and Ground Source Return cannot be secondary-injection tested. The solution is to rack breaker out of cradle/cell to isolate from the MDGF system. If it is a fixed breaker, then remove MDGF wiring from terminals M1, M2 and M3 while using the FFTK (Full Function Test Kit).
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