GE D30 Instruction Manual page 361

CHAPTER 5: SETTINGS
If one or both sources are de-energized, the synchrocheck programming can allow for closing of the circuit breaker using
undervoltage control to bypass the synchrocheck measurements (dead source function).
— This setting selects the source for voltage V1 (see the Notes section that follows).
SYNCHK1 V1 SOURCE
— Selects the source for voltage V2, which must not be the same as used for the V1 (see Notes).
SYNCHK1 V2 SOURCE
— Selects the maximum primary voltage difference in volts between the two sources. A primary
SYNCHK1 MAX VOLT DIFF
voltage magnitude difference between the two input voltages below this value is within the permissible limit for
synchronism.
— Selects the maximum angular difference in degrees between the two sources. An angular
SYNCHK1 MAX ANGLE DIFF
difference between the two input voltage phasors below this value is within the permissible limit for synchronism.
SYNCHK1 MAX FREQ HYSTERESIS
condition becomes satisfied when the frequency difference becomes lower than
Synchrocheck element has operated, the frequency difference must increase above the
sum to drop out (assuming the other two conditions, voltage and angle, remain satisfied).
MAX FREQ HYSTERESIS
SYNCHK1 DEAD SOURCE SELECT
function and permit the breaker to be closed when one or both of the two voltages (V1 or/and V2) are below the maximum
voltage threshold. A dead or live source is declared by monitoring the voltage level. Six options are available:
None — Dead Source function is disabled
LV1 and DV2 — Live V1 and Dead V2
DV1 and LV2 — Dead V1 and Live V2
DV1 or DV2 — Dead V1 or Dead V2
DV1 Xor DV2 — Dead V1 exclusive-or Dead V2 (one source is Dead and the other is Live)
DV1 and DV2 — Dead V1 and Dead V2
— Establishes a maximum voltage magnitude for V1 in 1 'pu'. Below this magnitude, the V1
SYNCHK1 DEAD V1 MAX VOLT
voltage input used for synchrocheck is considered "Dead" or de-energized.
— Establishes a maximum voltage magnitude for V2 in 'pu'. Below this magnitude, the V2
SYNCHK1 DEAD V2 MAX VOLT
voltage input used for synchrocheck is considered "Dead" or de-energized.
— Establishes a minimum voltage magnitude for V1 in 'pu'. Above this magnitude, the V1 voltage
SYNCHK1 LIVE V1 MIN VOLT
input used for synchrocheck is considered "Live" or energized.
— This setting establishes a minimum voltage magnitude for V2 in 'pu'. Above this magnitude,
SYNCHK1 LIVE V2 MIN VOLT
the V2 voltage input used for synchrocheck is considered "Live" or energized.
Notes on the synchrocheck function
1. The selected sources for synchrocheck inputs V1 and V2 (which must not be the same source) can include both a
three-phase and an auxiliary voltage. The relay automatically selects the specific voltages to be used by the
synchrocheck element in accordance with the following table.
Number V1 or V2 (source Y)
1 Phase VTs and
Auxiliary VT
2 Phase VTs and
Auxiliary VT
3 Phase VT
4 Phase VT and Auxiliary
VT
5 Auxiliary VT
D30 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
— Specifies the required hysteresis for the maximum frequency difference condition. The
— Selects the combination of dead and live sources that bypass the synchronism check
V2 or V1 (source Z)
Phase VTs and
Auxiliary VT
Phase VT
Phase VT
Auxiliary VT
Auxiliary VT
SYNCHK1 MAX FREQ DIFF
SYNCHK1 MAX FREQ DIFF + SYNCHK1
Auto-selected combination
Source Y Source Z
Phase Phase
Phase Phase
Phase Phase
Phase Auxiliary
Auxiliary Auxiliary
CONTROL ELEMENTS
. Once the
5
Auto-selected
voltage
VAB
VAB
VAB
V auxiliary
(as set for source Z)
V auxiliary
(as set for selected
sources)
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