GE Industrial Solutions Entellisys 5.0 User Manual - Manual (Page 139)

Downstream Zone Selective Interlocking 139
7
7.5.3 Test
To confirm that the Downstream ZSI inputs are wired correctly and the Downstream trip unit is
correctly restraining the Entellisys feeder breaker, the downstream trip unit must be forced into
pickup using primary injection or through a test kit purposed for use with the downstream trip
unit. The Entellisys system will record the following events; “Downstream ZSI Operated” and
“Downstream ZSI Dropout” if correctly configured.
Downstream external ZSI delay settings should be verified that they are longer than the
downstream device.
“Downstream External ZSI Operated” and “Downstream External ZSI Dropout” events
acknowledges the downstream ZSI signal. If these events are received during a test of the
downstream trip unit, no further testing is required to ensure the correct operation of
Downstream ZSI.
Figure 7-14 Event log during a downstream ZSI event.