GE 750 Instruction Manual page 460

17.9 CONTROL SCHEMES
18. While monitoring ∆φ on the display, slowly increase the line voltage lagging phase position until the "Out of
Sync" alarm is no longer displayed. Check that the angle difference is the selected value. Return the line
voltage angle to 0°.
19. Set the line voltage frequency to a value lower than allowed by the maximum frequency difference.
20. While monitoring ∆F on the display, slowly increase the line voltage frequency until the "Out of Sync" alarm
is no longer displayed. Check that the frequency difference is the selected value.
21. Set the line voltage to a frequency higher than permitted by the maximum frequency difference.
22. The "Out of Sync" alarm will be displayed as the frequency difference is above the maximum difference
requirement. While monitoring ∆F on the display, slowly decrease the line voltage frequency until the "Out
of Sync" alarm is no longer displayed. Check that the frequency difference is the selected value. Turn volt-
ages off.
If the Dead Source Permissive feature is to be used, set the Maximum Voltage Difference, Maximum Angle Dif-
ference, and Maximum Frequency Difference setpoints to the minimum values; and the Dead Source Permis-
sive, Dead Bus Maximum Voltage, Dead Line Maximum Voltage, Live Bus Minimum Voltage, and Live Line
Minimum Voltage setpoints to the required settings.
For a
DEAD SOURCE PERMISSIVE
1. Set the bus voltage to a magnitude above the dead-bus level, and nominal frequency and inject into the
relay.
2. Set the line voltage to a magnitude above the dead-line level, 180° out-of-phase with the bus voltage, at
the same frequency, and inject into the relay. This ensures synchronism cannot be achieved. The "Out of
Sync" alarm will be displayed as both the bus and line voltages are above their dead-setting limits.
3. Turn the bus voltage off. The "Out of Sync" alarm will be displayed as line voltage is above the dead limit.
4. Slowly reduce the line voltage, until the "Out of Sync" alarm is no longer displayed. This should be at the
dead line max volt limit. Return the voltages to the level prior to the reduction.
5. The "Out of Sync" alarm will be displayed as both the bus and line voltages are above their dead-setting
limits.
6. Turn the line voltage off. The "Out of Sync" alarm will be displayed.
7. Slowly reduce the bus voltage, until the "Out of Sync" alarm is no longer displayed. This should be at the
17
dead bus max volt limit. Turn the voltages off.
For a
DEAD SOURCE PERMISSIVE
1. Set the line voltage to nominal magnitude and frequency and inject into the relay. Set the bus voltage to a
magnitude above the dead-bus level, 180° out-of-phase with the line voltage, at the same frequency, and
inject into the relay. This ensures synchronism cannot be achieved.
2. The "Out of Sync" alarm will be displayed as the bus voltage is above its dead-setting limit.
3. Slowly reduce the bus voltage magnitude until the "Out of Sync" alarm is no longer displayed. This should
be at the dead bus max volt limit. Turn both voltages off. The "Out of Sync" alarm will be displayed as the
line voltage is below its minimum voltage setting limit.
4. Slowly increase the line voltage magnitude until the "Out of Sync" alarm is no longer be displayed. This
should be at the minimum live line voltage limit. Turn both voltages off.
17-
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Courtesy of NationalSwitchgear.com
setpoint of DB & DL , perform the following steps:
setpoint of LL & DB , perform the following steps:
750/760 Feeder Management Relay
17 COMMISSIONING
GE Power Management