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Can MDGF be combined with ZSI and ground fault

Product Line:
Powerpact P and R and Masterpact NT and NW
Resolution:
At present the installation of a MDGF (Modified Differential Ground Fault) Protection System employing MDGF Sensors and MDGF Modules is incompatible with the combination of GF (ground fault) ZSI (zone selective interlocking).  You can have one or the other but not both.  In fact, if you have an MDGF Protection System installed, then any function ZSI system between the mains and tie would be superfluous because when any tie CB is closed is effectively becomes a main circuit breaker to its downstream loads. The installation of any type of Short Time ZSI has no effect on MDGF and MDGF has no effect on ST ZSI.
 
For a fee SEES (Schneider Electric Engineering Services) creates custom MDGF design packages that includes BOMs, wiring diagrams, and test procedures.
 
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