GE L90 Instruction Manual page 568

CONTROL ELEMENTS
SYNCHK1 S-CLS MAX dF
disarmed when the slip frequency exceeds this setting.
SYNCHK1 S-CLS MIN dF
disarmed when the slip frequency drops below this setting.
SYNCHK1 S-CLS BRK TIME
SYNCHK1 V2 MAG CORR FACTOR
magnitude compensation so that V2 magnitude can be directly compared with V1 magnitude. For example, when V1 and
V2 are taken from 2 different windings of the transformer and at different voltage levels, the magnitude compensation
must be performed before starting magnitude comparison in synchrocheck element.
5
SYNCHK1 V2 ANGLE SHIFT
compared with V1 angle. For example, when V1 and V2 are taken from two different windings of the transformer and with
different angle shift due to winding connections, the angle shift compensation must be performed before starting angle
comparison in synchrocheck element.
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
SYNCHK1 DEAD V1 MAX VOLT
voltage input used for synchrocheck is considered "Dead" or de-energized.
SYNCHK1 DEAD V2 MAX VOLT
voltage input used for synchrocheck is considered "Dead" or de-energized.
SYNCHK1 LIVE V1 MIN VOLT
input used for synchrocheck is considered "Live" or energized.
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.
5-344
Figure 5-196: Synchrocheck plot for slip < 0 (slip = F2-F1)
— Specifies the maximum slip frequency allowed in Hz in the dynamic mode. The dynamic mode is
— Specifies the minimum slip frequency allowed in Hz in the dynamic mode. The dynamic mode is
— Specifies the breaker closing time in seconds.
— Specifies the magnitude correction factor of source V2. This setting is used for V2
— Specifies the angle of source V2 that needs to be shifted so that V2 angle can be directly
— Selects the combination of dead and live sources that bypass the synchronism check
— Establishes a maximum voltage magnitude for V1 in 1 'pu'. Below this magnitude, the V1
— Establishes a maximum voltage magnitude for V2 in 'pu'. Below this magnitude, the V2
— Establishes a minimum voltage magnitude for V1 in 'pu'. Above this magnitude, the V1 voltage
— This setting establishes a minimum voltage magnitude for V2 in 'pu'. Above this magnitude,
L90 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
CHAPTER 5: SETTINGS