Siemens siprotec 7SD5 User Manual page 499

the feeder in the direction of the busbar rotates the voltage. An example is shown in
Section 2.1.2.1.
If necessary, different transformation ratios of the transformers on the busbar and the
feeder may have to be considered under address 215 U-line / Usync.
The synchronism and voltage check must be switched ON under address 3501 FCT
Synchronism .
An additional help for the connection control are the messages 2947 „Sync.
Udiff>" and 2949 „Sync. ϕ-diff>" in the spontaneous annunciations.
• Circuit breaker is open. The feeder is isolated (zero voltage). The VTmcb's of both
• For the synchronism check the program OVERRIDE = YES (address 3519) is set;
• Via binary input (No. 2906 „>Sync. Start AR") initiate the measuring request.
• Set address 3519 OVERRIDE to NO.
• Then the circuit breaker is closed while the line isolator is open (see Figure 3-29).
• The program SYNC-CHECK = YES (address 3515) is set for synchronism check.
• Via binary input (No. 2906 „>Sync. Start AR") initiate the measuring request.
Figure 3-29
7SD5 Manual
C53000-G1176-C169-1
voltage transformer circuits must be closed.
the other programs (addresses 3515 to 3518) are set to NO.
The synchronism check must release closing (message „Sync. release", FNo.
2951). If not, check all relevant parameters again (synchrocheck configured and
enabled correctly, see Sections 2.1.1.3, 2.1.2.1 and 2.16.2).
Both voltage transformers therefore measure the same voltage.
The synchronism check must release closing (message „Sync. release", FNo.
2951).
Measuring voltages for the synchronism check
3.3 Commissioning
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