Siemens SIPROTEC 4 7VE61, Manual, Page: 39 / 330

1 1 /
2
-channel Version
In the 1 1 /
2
-channel version of the 7VE61 the paralleling function issues the closure command. The synchro-
check function operates as an enable criterion and is set coarsely in the monitoring limits. The existing
dependences for the setting values of the enable angle, the permissible frequency difference and the circuit
breaker closing time make a little narrow the working range of the 7VE61 compared with the 2 channels
7VE63 ( see the Seting Notes of the synchocheck).
2-channel Version
In 2-channel version of the 7VE63 two procedures independent of one another operate in parallel. The closure
command is issued if both procedures decide for closure. The uniformity of the two channel device design is
shown in the following figure.
[ve6-zweikanaligkeit-030205-kn, 1, en_GB]
Figure 2-8 2- channel version
Uniform Multichannel Redundancy
To ensure high safety and reliability, not only the software was developed in diverse forms, but also essential
hardware components were duplicated. In accordance with
Figure 2-8 or Figure 2-3 the voltage inputs (U1
and U1 as well as U2 and U2) are duplicated and fed to two analog/digital converters. Measurement procedure
1 operates exclusively with voltages U1 and U2 and measurement procedure 2 with voltages rotated by 180°
(U1 or U2). In the 1
1 /
2
channel version in measurement procedure 1 the synchrocheck function is applied and
in measurement procedure 2 the parallel switch function. With the 2-channel version in measurement proce-
dures 1 and 2 different parallel switch algorithms are processed.
If both procedures decide for closure, enabling is allocated for activating the breaker semiconductors. Two
closure relays are activated each by two semiconductors. This avoids overfunctioning by semiconductor
shorting. Further safety is provided acc. to
Figure 2-8 by the relay activation using the cross measurement
procedure. The closure coils are activated by the contacts of the two relays. External interconnection is to be
done such that the plus pole and the minus pole are separately switched.
Measurement Methods
To conform to multichannel redundancy, two diverse measurement algorithms are used. This excludes over-
functioning due to systematic errors. At the same time measurement procedures of different programmers are
used, processed in independent tasks, and use different memory parts.
Functions
2.2 Paralleling Functions
SIPROTEC 4, 7VE61 and 7VE63, Manual 39
C53000-G1176-C163-3, Edition 10.2017