5-182 F60 Feeder Protection System GE Multilin
5.6 GROUPED ELEMENTS 5 SETTINGS
5
The phase directional element responds to the forward load current. In the case of a following reverse fault, the ele-
ment needs some time – in the order of 8 ms – to establish a blocking signal. Some protection elements such as
instantaneous overcurrent may respond to reverse faults before the blocking signal is established. Therefore, a
coordination time of at least 10 ms must be added to all the instantaneous protection elements under the supervi-
sion of the phase directional element. If current reversal is of a concern, a longer delay – in the order of 20 ms –
may be needed.
Figure 5–73: PHASE DIRECTIONAL SCHEME LOGIC
5.6.5 NEUTRAL CURRENT
a) MAIN MENU
PATH: SETTINGS GROUPED ELEMENTS SETTING GROUP 1(6) NEUTRAL CURRENT
NEUTRAL CURRENT
NEUTRAL TOC1
See page 5–183.
MESSAGE
NEUTRAL TOC2
See page 5–183.
MESSAGE
NEUTRAL TOC3
See page 5–183.
MESSAGE
NEUTRAL TOC4
See page 5–183.
MESSAGE
NEUTRAL IOC1
See page 5–184.
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FLEXLOGIC OPERAND
FLEXLOGIC OPERAND
FLEXLOGIC OPERAND
FLEXLOGIC OPERAND
SETTING
SETTING
SETTING
SETTING
SETTING
SETTING
PHASE DIR 1
FUNCTION:
PHASE DIR 1 SOURCE:
PHASE DIR 1 BLOCK OC
WHEN V MEM EXP:
PHASE DIR 1
BLOCK:
PHASE DIR 1 ECA:
PHASE DIR 1 POL V
THRESHOLD:
PH DIR1 BLK A
PH DIR1 BLK B
PH DIR1 BLK C
PH DIR1 BLK
IA
No
Seq=ABC Seq=ACB
Yes
VBC VCB
827078A7.CDR
Off=0
V MINIMUM
-Use V when V Min
-Use V memory when
V < Min
I 0.05 pu
Enabled=1
AND
AND
OR
MEMORY TIMER
1 cycle
1 sec
Vpol
0
I
1
RUN
AND
PHASE B LOGIC SIMILAR TO PHASE A
PHASE C LOGIC SIMILAR TO PHASE A
OR
USE ACTUAL VOLTAGE
USE MEMORIZED VOLTAGE