GE Industrial Solutions EntelliGuard TU Trip Units - Manual (Page 34)

EntelliGuard TU Trip Units: UL/ANSI Models DEH-4567B
Setting up the Trip Unit
24 ©2012 General Electric All Rights Reserved
RELT INSTANTANEOUS PICKUP
The Reduced Energy Let-Thru (RELT)
element is a second Instantaneous
protection element that can be put
into force when the trip unit receives
an external input such as from a light
curtain or switch contact.
RELT Pickup defines the threshold
where the RELT INST element begins
to “timeout” toward tripping, as a
multiple of the Rating Plug current.
RELT is an optional element. If it is not
installed on your trip unit, this screen will not appear.
RELT is adjustable between 1.5 and a breaker frame-
dependent maximum, similar to the INST element.
RELT cannot be disabled via the Pickup Setpoint.
When RELT is provided in the trip unit, Digital Output 1 is
automatically and permanently assigned to indicate
whether RELT is engaged or not. Digital Input 1 is
automatically and permanently assigned as a means to
engage RELT with an external contact. RELT can also be
put into effect via serial communications command. Please
refer to the section on Digital Input/Output configuration or
Modbus for details on how to setup RELT.
What this shows:
The Pickup setpoint is highlighted and set to 1.5 x the
Rating Plug current.
GROUND FAULT SUM PICKUP
The Ground Fault Sum element
protects the electrical system against
unintentional connections to earth
ground.
Ground Fault Sum Pickup defines the
threshold where the GF Sum element
begins to “timeout” toward tripping,
as fraction of the breaker sensor
value.
GF Summation always uses four
current sensor inputs (Phase A, B, C,
and N) to calculate a phasor sum
when determining pickup.
Ground Fault Summation is an optional element. If GF Sum
is not installed in your trip unit, this screen will not appear.
For ANSI and UL breakers the GF Sum pickup adjustment
range is between 0.2 and 0.6. Both the minimum and
maximum are breaker and application dependent.
Use DES-093 for EntelliGuard G GF curve characteristics
and DES-098A for Power Break, AKR, and Wavepro GF
curve characteristics.
What this shows:
The Pickup setpoint is highlighted and set to 0.2x the
breaker’s installed sensor rating.
GROUND FAULT SUM DELAY
Ground Fault Sum 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.
See DES-098A for trip time curve
information on Power Break, AKR, and
Wavepro.
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.
NOTICE
When ZSI is ON this becomes the PROTECTIVE,
UNRESTRAINED SETTING, not the selective setting and
the ZSI setting becomes the SELECTIVE, RESTRAINED
SETTING. In other words, when there is no ZSI input,
these GF settings are in effect.
GROUND FAULT SUM SLOPE
Ground Fault Slope modifies the
shape of the “delay band” for the GF
element.
See DES-093 for trip time curve
information on EntelliGuard G (shown
below).
See DES-098A for trip time curve
information on Power Break, AKR, and
Wavepro.
The Slope setpoint has these possible
values:
• OFF – definite-time delay
• 1 – l
2 t
• 2 – l 4 t
• 3 – SGF slope