GE Industrial Solutions EntelliGuard TU Trip Units - Manual (Page 37)

DEH-4567B EntelliGuard TU Trip Units: UL/ANSI Models
Setting up the Trip Unit
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The available ZSI setting combinations (available selections
vary by options):
• OFF
• GF ONLY
• GF & ST
• ST ONLY
• INST ONLY
• GF-INST
• ST-INST
• GF-INST-ST
ZSI can be configured in the following combinations: OFF,
GF only, GF & ST, ST only, INST only, GF & INST, ST & INST,
and GF-ST-IN.
What this shows:
This screen shows you which combination of protection
elements participate with ZSI to provide enhanced
coordination.
ZONE SELECTIVE INTERLOCK SHORT TIME (ST) SETUP
The Zone Selective Interlock (ZSI) ST
setting is an alternative ST delay band
and slope combination that will
override the GTU ST setpoints
whenever the trip unit receives a valid
ZSI input signal. This equates to the
RESTRAINED, selective setting.
The normal short time setting
becomes the unrestrained, protective
setting.
ZSI is an optional element. If ZSI is not
installed in your trip unit, this screen
will not appear.
If ZSI is installed, but it is not
configured to operate with the ST
element, this screen will not appear.
If the ST element is turned OFF
(disabled) the ZSI ST element is also
disabled, regardless of the setting on this screen.
What this shows:
The ST Delay band configuration that will be put in force
when the ZSI input signal is active
ZONE SELECTIVE INTERLOCK GROUND FAULT SETUP
The Zone Selective Interlock (ZSI) GF
setting sets an alternative GF delay
band and slope setpoint combination
that will override the GTU GF
setpoints whenever the trip unit
receives a valid ZSI input signal.
ZSI is an optional element. If ZSI is not
installed in your trip unit, this screen
will not appear.
If ZSI is installed, but it is not
configured to operate with the GF
element, this screen will not appear.
If the GF element is disabled, the ST GF element is also
disabled, regardless of the value displayed here.
What this shows:
The GF Delay band configuration that will be put in force
when the ZSI input signal is active.
PROTECTIVE RELAY ENABLED
The Protective Relay setting screen
enables or disables tripping for
protective relays:
• OFF – protective relays will not
trip the breaker
• ON – protective relays will trip the
breaker if the relay is configured to
trip.
Protective Relaying is an optional
feature. If it is not installed on the trip
unit, this screen will not appear.
Each relay can be disabled singly – so you can turn all of
them off with this screen, and allow any that are
configured to trip to do so.
VOLTAGE UNBALANCE RELAY