GE Industrial Solutions EntelliGuard TU Trip Units - Manual (Page 36)

EntelliGuard TU Trip Units: UL/ANSI Models DEH-4567B
Setting up the Trip Unit
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GROUND FAULT CT SLOPE
Ground Fault CT Slope modifies the
shape of the “delay band” for the GF
element.
See DES-093 for trip time curve
information on EntelliGuard G.
The Slope setpoint has three available
values:
• OFF – constant-time delay band
• 1 – 3 – Increasing slope values,
with 1 being the lowest, 3 the highest.
What this shows:
The GF Slope is set to OFF (Constant Time).
GROUND FAULT SUM ALARM
This is the Ground Fault Sum Alarm Setup Screen.
GF Sum Alarm operates identically to GF Sum Protection,
but instead of tripping the circuit breaker, Alarm will raise a
flag available over Modbus, or it can be configured to
energize a digital output for external signaling.
See the section on Digital Output configuration for
information on how to set up an external contact closure
on GF Sum Alarm activation.
See DES-093 for trip time curve information on EntelliGuard
G.
See DES-098a for trip time curve information on legacy
breakers.
GROUND FAULT CT ALARM
This is the Ground Fault CT Alarm Setup Screen.
GF CT Alarm operates identically to GF CT Protection, but
instead of tripping the circuit breaker, Alarm will raise a flag
available over Modbus, or it can be configured to energize
a digital output for external signaling.
See the section on Digital Output configuration for
information on how to set up an external contact closure
on GF CT Alarm activation.
GF CT is available only EntelliGuard G circuit breakers.
See DES-093 for trip time curve information on EntelliGuard
G.
ZONE SELECTIVE INTERLOCKING SETUP
The optional Zone Selective
Interlocking (ZSI) feature allows
enhanced coordination of tiered
breaker installations.
The Zone Selective Interlocking
setting lets you select which
protection elements will participate
in the ZSI scheme – a combination of
GF, ST and/or Instantaneous, or
none. The options available for
selection are dependent on which
factory options were ordered on the
trip unit. If no ZSI option is installed on the trip unit, this
screen will not appear.
When a trip unit equipped with ZSI receives a signal on its
ZSI Input terminals, it will adjust the delay band settings for
the configured protection elements to delay tripping, giving
the downstream breaker time to clear the fault.