Siemens siprotec SJ62 User Manual page 298

Asynchronous
Conditions
Synchronous Con-
ditions
SIPROTEC 4, 7SJ62/63/64 Handbuch
C53000-G1140-C147-A, Edition 07.2015
The synchronizing function of the 7SJ64 can issue a close command also for asyn-
chronous power systems such that, considering the circuit breaker operating time (ad-
dress 6x20), the power systems are coupled when the phases are equal.
Parameters 6x30dV ASYN V2>V1 and 6x31dV ASYN V2<V1 can be set to adjust
the permissible voltage differences asymmetrically.
Parameters 6x32df ASYN f2>f1 and 6x33df ASYN f2<f1 limit the operating
range for asynchronous switching. The availability of two parameters enables an
asymmetrical range for closing to be set.
With address 6x40 SYNC PERMIS. a selection can be made to only check for syn-
chronism conditions when the frequency is below the threshold F SYNCHRON (YES) or
whether to operate with the asynchronous conditions over the entire frequency range
(NO).
Address 6x41F SYNCHRON is an automatic threshold between synchronous and asyn-
chronous switching. If the frequency difference is below the specified threshold, the
power systems are considered to be synchronous and the conditions for synchronous
switching apply. If it is above the threshold, the switching is asynchronous with consid-
eration of the time left until the voltages are in phase.
Address 6x42dV SYNC V2>V1 and 6x43dV SYNC V2<V1 can be used to set the
permissible voltage differences asymmetrically.
Address 6x44dα SYNC α2> α1 and 6x45dα SYNC α2< α1 confine the operating
range for synchronous switching. These two parameters allow an asymmetrical
switching range to be configured (see Figure 2-108).
Moreover, the release time delay T SYNC-DELAY (address 6x46) can be set during
which all synchronous conditions must at least be fulfilled for the closing command to
be generated after expiration of this time.
Figure 2-108 Switching under synchronous system conditions
2.19 Synchronism and Voltage Check 25 (7SJ64 only)
296