GE 750 Instruction Manual page 393

CHAPTER 7: COMMISSIONING
750 FEEDER MANAGEMENT RELAY – INSTRUCTION MANUAL
 Turn the bus voltage off.
The "Out of Sync" alarm will be displayed as line voltage is above the
dead limit.
 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.
 The "Out of Sync" alarm will be displayed as both the bus and line
voltages are above their dead-setting limits.
 Turn the line voltage off.
The "Out of Sync" alarm will be displayed.
 Slowly reduce the bus voltage, until the "Out of Sync" alarm is no
longer displayed.
This should be at the dead bus max volt limit.
 Turn the voltages off.
For a
DEAD SOURCE PERMISSIVE
 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.
 The "Out of Sync" alarm will be displayed as the bus voltage is above
its dead-setting limit.
 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.
 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.
For a
DEAD SOURCE PERMISSIVE
 Set the bus voltage to nominal magnitude and frequency and inject into
the relay.
 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 the line voltage is above
its dead-setting limit.
setpoint of "LL & DB", perform the following steps:
setpoint of "DL & LB", perform the following steps:
CONTROL SCHEMES
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