Synchrocheck - Siemens siprotec SJ62 User Manual

Operating Range
Measured Values

2.19.1.2 Synchrocheck

SIPROTEC 4, 7SJ62/63/64 Handbuch
C53000-G1140-C147-A, Edition 07.2015
is smaller than Address 6x03 (lower voltage limit Vmin). The synchrocheck cannot be
bypassed via binary input.
If the monitoring function Fuse-Failure-Monitor is used and if it has picked up at the
same time as the measurement of the synchronization was requested, the synchroni-
zation is not started either (message „25 Sync. Error"). The same applies, if a
voltage transformer failure (m.c.b. tripping) is communicated to the device via binary
inputs 6509 „>FAIL:FEEDER VT" or 6510 „>FAIL: BUS VT". In this case, the syn-
chrocheck can be bypassed via binary input.
The operating range of the synchrocheck is defined by the configured voltage thresh-
olds Vmin and Vmax, and the fixed frequency band f
If measurement is started and one or both voltages are outside the operating range,
or one voltage leaves the permissible range, corresponding messages indicate this
behaviour („25 f1>>", „25 f1<<", „25 V1>>", „25 V1<<", etc.).
The measured values of the synchrocheck are displayed in separate boxes for prima-
ry, secondary and percentage values. The measured values are displayed and
updated only while a synchrocheck is requested.
The following is displayed:
• Value of reference voltage V
• Value of the voltage to be synchronized V
• Frequency values f
1
• Differences of Voltage, Frequency and Angle.
Having selected operating mode SYNCHROCHECK the mode verifies the synchronism
before connecting the two system components and cancels the connecting process if
parameters for synchronism lie outside the configured thresholds.
Before a release is granted, the following conditions are checked:
• Is the reference voltage V
voltage Vmax?
to be synchronized above the setting value Vmin but below the
• Is the voltage V
2
maximum voltage Vmax?
• Is the voltage difference V
• Is the voltage difference V
• Are the two frequencies f
• Is the frequency difference f
f2>f1?
• Is the frequency difference f
f2<f1?
• Is the angle difference α
• Is the angle difference α
2.19 Synchronism and Voltage Check 25 (7SJ64 only)
1
2
and f
2
above the setting value Vmin but below the maximum
1
within the permitted threshold dV SYNCHK V2>V1?
– V
2 1
within the permitted threshold dV SYNCHK V2<V1?
– V
1 2
and f within the permitted operating range f
1 2
within the permitted threshold df SYNCHK
– f
2 1
within the permitted threshold df SYNCHK
– f
1 2
– α within the permitted threshold dα SYNCHK α2>α1?
2 1
– α within the permitted threshold dα SYNCHK α2<α1?
1 2
± 3 Hz.
Nom
± 3 Hz?
N
286