GE Industrial Solutions EntelliGuard TU Trip Units - Manual (Page 35)

DEH-4567B EntelliGuard TU Trip Units: UL/ANSI Models
Setting up the Trip Unit
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NOTICE
When ZSI is ON this becomes the PROTECTIVE,
UNRESTRAINED SETTING, not the selective setting and
the ZSI setting becomes the SELECTIVE, RESTRAINED
SETTING.
What this shows:
The GF Slope is set to OFF (Constant Time).
Figure 3-2: Ground Fault Sum Slope, Options 1 – 2
Figure 3-3: Ground Fault Sum Slope, Option 3
GROUND FAULT CT PICKUP (ENTELLIGUARD G ONLY)
The Ground Fault CT element
protects the electrical system against
unintentional connections to earth
ground.
Ground Fault CT Pickup defines the
threshold where the GF CT element
begins to “timeout” toward tripping,
as fraction of the breaker sensor
value.
GF CT is used with Multi-Source
Ground Fault installations.
Ground Fault CT is an optional element. If GF CT is not
installed in your trip unit, this screen will not appear.
GF CT is available only on EntelliGuard G circuit breakers.
The GF Sum pickup adjustment range is between 0.1 and
1.0. Both the minimum and maximum are breaker and
application dependent.
Settings below 0.2 require an external 24VDC power supply
for proper operation.
What this shows:
The Pickup setpoint is highlighted and set to 0.2 x the
breaker’s installed sensor rating.
GROUND FAULT CT DELAY
Ground Fault CT Band selects the
“delay band” for the GF element, or
how long the trip unit will allow an
overload to persist before the breaker
is commanded to open.
See DES-093 for trip time curve
information on EntelliGuard G.
Ground Fault Trip protection delay
band can be set between 1 and 14.
Optional configurations will allow for
GF to be turned off by setting the
delay band to OFF. This value is found between the
minimum and maximum band selections for the trip unit.
GF CT is available only on EntelliGuard G circuit breakers.
L 2 t = Slope = 1
L 4 t = Slope = 2
SGF = Slope = 3