GE Multilin L60, Instruction Manual

Page: 283 / 752

GE Multilin L60 Line Phase Comparison System 5-153
5 SETTINGS 5.5 GROUPED ELEMENTS
5
• NEG SEQ di/dt FD EVENTS : This setting controls event recording of the function. These events are logged indepen-
dently from the 87PC events.
Figure 5–55: NEGATIVE-SEQUENCE CURRENT RATE OF CHANGE FAULT DETECTOR LOGIC
f) RATE OF CHANGE OF POSITIVE-SEQUENCE CURRENT FAULT DETECTION
PATH: SETTINGS

GROUPED...

PHASE COMPARISON...

ADVANCED FAULT...

RATE OF CHANGE OF POS SEQ CURRENT
The element responds to the vector difference of the positive-sequence current phasors taken at the present moment and
one-half a power system cycle earlier. Two current thresholds are provided for the low-set and high-set operation control-
ling keying and tripping. The raw
di / dt condition of the element detects the change and resets when reaching a steady
state fault condition. As such, a seal-in timer is provided to maintain the detected fault condition for a user specified period
of time.
• POS SEQ di/dt FD FUNCTION : This setting enables or disables the rate of change of positive-sequence current fault
detection. Note that all fault detectors operate in parallel toward the 87PC function. If not required, a given fault detec-
tor shall be disabled. To effectively disable the overcurrent fault detectors under the main 87PC menu, set their thresh-
old very high.

RATE OF CHANGE OF
 POS SEQ CURRENT
POS SEQ di/dt FD
FUNCTION: Disabled
Range: Disabled, Enabled
MESSAGE
POS SEQ di/dt FDL
PICKUP: 0.10 pu
Range: 0.01 to 5.00 pu in steps of 0.01
MESSAGE
POS SEQ di/dt FDL
SEAL-IN: 0.600 s
Range: 0.000 to 10.000 s in steps of 0.001
MESSAGE
POS SEQ di/dt FDH
PICKUP: 0.50 pu
Range: 0.01 to 5.00 pu in steps of 0.01
MESSAGE
POS SEQ di/dt FDH
SEAL-IN: 0.200 s
Range: 0.000 to 10.000 s in steps of 0.001
MESSAGE
POS SEQ FDH SUPV:
Off
Range: any FlexLogic operand
MESSAGE
POS SEQ di/dt BLK:
Off
Range: any FlexLogic operand
MESSAGE
POS SEQ di/dt FD
TARGET: Self-reset
Range: Self-Reset, Latched, Disabled
MESSAGE
POS SEQ di/dt FD
EVENTS: Disabled
Range: Disabled, Enabled
831800A2.CDR
| I_2 - I_2* |
(summed
current)
FAST MEASUREMENTS
F1 PHASE CT BANK:
Neg-seq current, I_2
L1 PHASE CT BANK:
Neg-seq current, I_2
SETTINGS
NEG SEQ di/dt
FDL PICKUP:
NEG SEQ di/dt
FDH PICKUP:
> FDL PICKUP
> FDH PICKUP
87PC dI2/dt FDH OP
Hardwired to the
87PC function
RUN
AN
D
Enabled = 1
Off = 0
SETTINGS
NEG SEQ di/dt
FD FUNCTION:
NEG SEQ di/dt
BLK:
(*) value delayed
by 0.5 cycle
0
t
DPO
TIMERS
NEG SEQ di/dt
FDL SEAL-IN:
0
t
DPO
87PC dI2/dt FDL OP
FLEXLOGIC
OPERANDS
NEG SEQ di/dt
FDH SEAL-IN:
OR
AN
D
SETTINGS
NEG SEQ FDH
SUPV:
Off = 0
Σ