Siemens SIPROTEC 7SJ62 User Manual

Functions
2.19 Synchronization Function
SIPROTEC, 7SJ62/64, Manual
C53000-G1140-C207-2, Release date 01.2008
309
2.19.1.2 Synchrocheck
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 config-
ured thresholds.
Before a release is granted, the following conditions are checked:
• Is the reference voltage V
1
above the setting value Vmin but below the maximum voltage Vmax?
• Is the voltage V
2
to be synchronized above the setting value Vmin but below the maximum voltage Vmax?
• Is the voltage difference V
2
– V
1
within the permitted threshold dV SYNCHK V2>V1?
• Is the voltage difference V
1
– V
2
within the permitted threshold dV SYNCHK V2<V1?
• Are the two frequencies f
1
and f
2
within the permitted operating range f
Nom
± 3Hz?
• Is the frequency difference f
2
– f
1
within the permitted threshold df SYNCHK f2>f1?
• Is the frequency difference f
1
– f
2
within the permitted threshold df SYNCHK f2<f1?
• Is the angle difference α
2
– α
1
within the permitted threshold dα SYNCHK α2>α1?
• Is the angle difference α
1
– α
2
within the permitted threshold dα SYNCHK α2<α1?
2.19.1.3 Synchronous / Asynchronous (only 7SJ64)
The operating mode ASYN/SYNCHRON uses the frequency slip of the two power systems (parameter F
SYNCHRON) to determine whether the power systems are asynchronous to each other ("Switching under Asyn-
chronous System Conditions") or synchronous ("Switching under Synchronous System Conditions"). The syn-
chronous condition is indicated by the message „Sync f syn“ (170.2332). If the systems are asynchronous,
the time window for switching is passed relatively quickly. Therefore, it is sensible to take the operating time of
the circuit breaker into account. Thus the device can issue the ON command at a time where asynchronous
conditions are still prevailing. As soon as the poles make contact the conditions will be synchronous.
It is also possible to generally take into account the operating time of the circuit breaker, i.e. also with synchro-
nous conditions prevailing.
Switching under Synchronous System Conditions
Switching under synchronous conditions means that the ON command will be released as soon as the charac-
teristic data (voltage difference, angle difference) are within the thresholds specified by configuration.
Before granting a release for closing under synchronous conditions, the following conditions are checked:
• Is the reference voltage V
1
above the setting value Vmin but below the maximum voltage Vmax?
• Is the voltage V
2
to be synchronized above the setting value Vmin but below the maximum voltage Vmax?
• Is the voltage difference V
2
– V
1
within the permitted threshold dV SYNC V2>V1?
• Is the voltage difference V
1
– V
2
within the permitted threshold dV SYNC V2<V1?
• Are the two frequencies f
1
and f
2
within the permitted operating range f
Nom
± 3Hz?
• Is the frequency difference smaller than the configured threshold frequency difference F SYNCHRON which
defines the transition from synchronous to asynchronous systems?
• Is the angle difference α
2
– α
1
within the permitted threshold dα SYNC α2> α1?
• Is the angle difference α
1
– α
2
within the permitted threshold dα SYNC α2< α1?
As soon as all synchronism conditions are fulfilled, the message „25 Synchron“ is issued.
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Siemens SIPROTEC 7SJ62 Specifications

General

Brand	Siemens
Model	SIPROTEC 7SJ62
Category	Relays
Language	English