GE T35 Instruction Manual page 251

5 SETTINGS
c) INSTANTANEOUS DIFFERENTIAL

PATH: SETTINGS GROUPED ELEMENTS
 INSTANTANEOUS
 DIFFERENTIAL
MESSAGE
MESSAGE
MESSAGE
MESSAGE
The instantaneous differential element acts as an instantaneous overcurrent element responding to the measured differen-
tial current magnitude (filtered fundamental frequency component) and applying a user-selectable pickup threshold. The
pickup threshold should be set greater than the maximum spurious differential current that could be encountered under
non-internal fault conditions (typically magnetizing inrush current or an external fault with extremely severe CT saturation).
SETTING
INST DIFFERENTIAL
FUNCTION:
Disabled=0
Enabled=1
SETTING
INST DIFF BLOCK:
Off=0
ACTUAL VALUE
DIFF PHASOR
Iad
Ibd
Icd
Figure 5–45: INSTANTANEOUS DIFFERENTIAL SCHEME LOGIC
GE Multilin
 
SETTING GROUP 1(6) TRANSFORMER
INST DIFFERENTIAL
FUNCTION: Disabled
INST DIFFERENTIAL
PICKUP: 8.000 pu
INST DIFF BLOCK:
Off
INST DIFFERENTIAL
TARGET: Self-reset
INST DIFFERENTIAL
EVENTS: Disabled
SETTING
INST DIFFERENTIAL
PICKUP:
RUN
AND
Iad > PICKUP
RUN
Ibd > PICKUP
RUN
Icd > PICKUP
T35 Transformer Protection System
5.6 GROUPED ELEMENTS

INSTANTANEOUS DIFFERENTIAL
Range: Disabled, Enabled
Range: 2.000 to 30.000 pu in steps of 0.001
Range: FlexLogic™ operand
Range: Self-reset, Latched, Disabled
Range: Disabled, Enabled
FLEXLOGIC OPERANDS
XFMR INST DIFF OP A
XFMR INST DIFF OP B
XFMR INST DIFF OP C
FLEXLOGIC OPERAND
OR XFMR INST DIFF OP
828000A1.CDR
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