GE Multilin L60, Инструкция по эксплуатации

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GE Multilin L60 Line Phase Comparison System 5-155
5 SETTINGS 5.5 GROUPED ELEMENTS
5
g) NEGATIVE-SEQUENCE OVERCURRENT FAULT DETECTION
PATH: SETTINGS

GROUPED ELEMENTS

PHASE COMPARISON ELEMENTS

ADVANCED FAULT DETECTORS

NEGATIVE-SEQUENCE CURRENT
The negative-sequence overcurrent advanced fault detector element responds to the increment of the magnitude of the
negative-sequence current over a specified threshold. Thresholds are provided for low-set control of keying and high-set
operation control of tripping.
The following settings are available.
• NEG SEQ I_2 FD FUNCTION : This setting enables or disables the negative-sequence overcurrent fault detection.
Note that all fault detectors operate in parallel with the 87PC function. To effectively disable the overcurrent fault detec-
tors under the main 87PC menu, set their threshold very high.
• NEG SEQ I_2 FDL PICKUP : This setting specifies the pickup of the low-set stage of the element used to control the
key operation. The nominal current of the phase CT bank of the relay is 1 pu.
• NEG SEQ I_2 FDH PICKUP : This setting specifies the pickup of the high-set stage of the element used to control the
trip operation. The nominal current of the phase CT bank of the relay is 1 pu.
• NEG SEQ I_2 BLK : The fault detector is hard-wired to the 87PC scheme. It can be disabled permanently using the
function setting or blocked temporarily with this setting. This setting selects a FlexLogic operand that blocks this fault
detector when asserted.
• NEG SEQ I_2 FD TARGET : This setting controls targets of the negative-sequence overcurrent advanced fault detector
function. These targets operate independently from the 87PC targets.
• NEG SEQ I_2 FD EVENTS : This setting controls event recording of the negative-sequence overcurrent advanced fault
detector function. These events are logged independently from the 87PC events.
Figure 5–57: NEGATIVE-SEQUENCE OVERCURRENT ADVANCED FAULT DETECTOR LOGIC

NEGATIVE-SEQUENCE

CURRENT
NEG SEQ I_2 FD
FUNCTION: Disabled
Range: Disabled, Enabled
MESSAGE
NEG SEQ I_2 FDL
PICKUP: 0.10 pu
Range: 0.02 to 5.00 pu in steps of 0.01
MESSAGE
NEG SEQ I_2 FDH
PICKUP: 0.50 pu
Range: 0.05 to 15.00 pu in steps of 0.01
MESSAGE
NEG SEQ I_2 BLK:
Off
Range: FlexLogic operand
MESSAGE
NEG SEQ I_2 FD
TARGET: Self-reset
Range: Self-Reset, Latched, Disabled
MESSAGE
NEG SEQ I_2 FD
EVENTS: Disabled
Range: Disabled, Enabled
Hardwired to the
87PC function
To square pulse
and transmit logic
SETTINGS
Enabled = 1
NEG SEQ I_2 FD FUNCTION
Off = 0
NEG SEQ I_2 BLOCK
AND
FAST MEASUREMENTS
Negative-sequence
current I_2
F1 PHASE CT BANK
L1 PHASE CT BANK
Negative-sequence
current I_2
Σ
SETTINGS
NEG SEQ I_2 FDH PICKUP
RUN
NEG SEQ I_2 FDL PICKUP
> (FDL PICKUP) / 4
> (FDH PICKUP) / 4
> (FDL PICKUP) / 4
> (FDH PICKUP) / 4
> FDL PICKUP
> FDH PICKUP
OR
OR
AND
AND
FLEXLOGIC OPERANDS
87PC I_2 FDL OP
87PC I_2 FDH OP
831030A2.CDR