Negative Sequence Overcurrent; Winding 1 (2/3) Negative Sequence Time Overcurrent - GE 745 TRANSFORMER MANAGEMENT RELAY Instruction Manual

5 SETPOINTS
This section contains the settings to configure the negative sequence overcurrent elements. Included are neg-
ative sequence time overcurrents for each winding, and negative sequence instantaneous overcurrents for
each winding.
S NEG SEQ OC
S [ENTER] for more
a) WINDING 1 (2/3) NEGATIVE SEQUENCE TIME OVERCURRENT
S W1 NEG SEQ TIME OC
S [ENTER] for more
W1 NEG SEQ TIME OC
FUNCTION: Disabled
W1 NEG SEQ TIME OC
TARGET: Latched
W1 NEG SEQ TIME OC
PICKUP: 0.25 x CT
W1 NEG SEQ TIME OC
SHAPE: Ext Inverse
W1 NEG SEQ TIME OC
MULTIPLIER: 1.00
W1 NEG SEQ TIME OC
RESET: Linear
W1 NEG SEQ TIME OC
BLOCK: Disabled
GE Power Management
This message indicates the start of the NEGATIVE SEQUENCE OVERCURRENT
section. To continue with these setpoints press
go to the next section.
This message indicates the start of the NEGATIVE SEQUENCE TIME
OVERCURRENT section for Winding 1 (2/3). To continue with these setpoints
press , or press
E N TE R M E SSA G E
Range: Disabled / Enabled
Range: Self-reset / Latched / None
Select None to inhibit the display of the target message when the element
operates. Thus an element whose "target type" is None never disables the
LED self-test feature since it cannot generate a displayable target message.
Range: 0.05 to 20.00 (steps of 0.01)
Enter the level of negative sequence current (in units of relay nominal
current) above which the W1 (2/3) negative sequence time overcurrent
element will pickup and start timing.
Range: Ext Inverse / Very Inverse / Norm Inverse / Mod Inverse / Definite
Time / IEC Curve A / IEC Curve B / IEC Curve C / IEC Short Inv /
IAC Ext Inv / IAC Very Inv / IAC Inverse / IAC Short Inv / FlexCurve
A / FlexCurve B / FlexCurve C
Select the time overcurrent curve shape to be used for the W1 (2/3) negative
sequence time overcurrent element. Section 5.9: TIME OVERCURRENT
CURVES on page 5–91 describes the time overcurrent curve shapes.
Range: 0.00 to 100.00 (steps of 0.01)
Enter the multiplier constant by which the selected time overcurrent curve
shape (the base curve) is to be shifted in time.
Range: Instantaneous / Linear
Select Linear reset to coordinate with electromechanical time overcurrent
relays, in which the reset characteristic (when the current falls below the
reset threshold before tripping) is proportional to ratio of "energy"
accumulated to that required to trip. Select Instantaneous reset to coordinate
with relays, such as most static units, with instantaneous reset
characteristics.
Range: Disabled / Logc Inpt 1 (2-16) /Virt Inpt 1 (2-16) / Output Rly 1 (2-8) /
SelfTest Rly / Virt Outpt 1 (2-5)
745 Transformer Management Relay

5.6.10 NEGATIVE SEQUENCE OVERCURRENT

E N TE R
to go to the next section.
5.6 S4 ELEMENTS
, or press to
M E SSA G E
5
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