Overfrequency - GE 750 Instruction Manual

S6 Monitoring
Table 5–19: Analog Output Parameters (Sheet 2 of 2)
Parameter Name
Ground Current Angle
Polarizing Current
Polarizing Current Angle
φA/φB/φC Real Power
φA/φB/φC Reactive Power
φA/φB/φC Apparent Power
φA/φB/φC Power Factor
Synchro Voltage
Synchro Voltage Angle
Synchro Frequency
Frequency Decay Rate
Positive/Negative/Zero Sequence Current
Pos/Neg/Zero Sequence Current Angle
Positive/Negative/Zero Sequence Voltage
Pos/Neg/Zero Sequence Voltage Angle
Synchro Voltage Difference
Synchro Angle Difference
Synchro Frequency Difference
Sensitive Ground Current
Sensitive Ground Current Angle
Neutral Voltage
Neutral Voltage Angle
1
Power and energy quantities auto-range to display units appropriate to power system size.

Overfrequency

OVERFREQUENCY
GE Multilin
Range / Units
0 to 359° Lag
0 to 65535 Amps
0 to 359° Lag
–3000.0 to 3000.0 MW
–3000.0 to 3000.0 Mvar
0.0 to 3000.0 MVA
0.00 Lead to 0.00 Lag
0.00 to 655.35 kV
0 to 359° Lag
20.00 to 65.00 Hz
–10.00 to 10.00 Hz/s
0 to 65535 Amps
0 to 359° Lag
0.00 to 655.35 kV
0 to 359° Lag
0.00 to 655.35 kV
0 to 359° Lag
20.00 to 65.00 Hz
0.00 to 655.35 A
0 to 359° Lag
0.00 to 655.35 kV
0 to 359° Lag
PATH: SETPOINTS S6 MONITORING
[ ] OVERFREQUENCY
FUNCTION: Disabled
OVERFREQUENCY
MESSAGE
RELAYS (3-7): -----
OVERFREQUENCY
MESSAGE
PICKUP: 60.50 Hz
OVERFREQUENCY
MESSAGE
DELAY:
A significant overfrequency condition, likely caused by a breaker opening and
disconnecting load from a particular generation location, can be detected and used
to quickly ramp the turbine speed back to normal. If this is not done, the over speed
can lead to a turbine trip, which would then subsequently require a turbine start up
before restoring the system. If the overfrequency turbine ramp down is successful,
the system restoration can be much quicker. The overfrequency monitoring feature
of the relay can be used for this purpose at a generating location.
The overfrequency feature is inhibited from operating unless the phase A voltage is
above 30% of nominal. When the supply source is energized, the overfrequency
delay timer will only be allowed to time when the 30% threshold is exceeded and
the frequency is above the programmed pickup level. In the same way, when an
overfrequency condition starts the overfrequency delay timer and the phase A
voltage falls below the 30% threshold before the timer has expired, the element will
reset without operating.
http://www.GEmultilin.com
Feeder Management Relay
Step Defaults
Min.
1 0
1 0
1 0
1
0.1 –100.0
1
0.1 –100.0
1
0.1 0.0
0.01 0.99 Lag
0.01 0.00
1 0
0.01 47.00
0.01 –0.50
1 0
1 0
0.01 0.00
1 0
0.01 0.00
1 0
0.01 47.00
0.01 0.00
1 0
0.01 0.00
1 0
OVERFREQUENCY
Range: Disabled,
Alarm, Control
Range: Any combination of 3 to 7
Auxiliary relays
Range: 20.00 to 65.00 Hz in steps of
0.01
Range: 0.0 to 6000.0 s in steps of 0.1
5.0 s
750/760
Channel
Type
Max.
359 A
2000 A
359 A
100.0 C
100.0 C
100.0 A
0.50 Lag B
100.00 A
359 A
63.00 B
0.50 C
2000 A
359 A
100.00 A
359 A
100.00 A
359 A
63.00 B
20.00 A
359 A
100.00 A
359 A
Alarm, Latched
5–89