Siemens SIPROTEC 7SJ61 Manual page 249

Figure 2-82
Standard Interlocking (fixed programming)
The standard interlockings contain the following fixed programmed tests for each switching device, which can
be individually enabled or disabled using parameters:
• Device Status Check (set = actual): The switching command is rejected, and an error indication is displayed
if the circuit breaker is already in the set position. If this check is enabled, then it works whether interlocking,
e.g. zone controlled, is activated or deactivated.
• System Interlocking: To check system interlocking, a local command is transmitted to the central unit with
Switching Authority = LOCAL. A switching device that is subject to system interlocking cannot be switched
by DIGSI.
• Zone Controlled/Bay Interlocking: Logic links in the device which were created via CFC are interrogated and
considered during interlocked switching.
• Blocked by Protection: A CLOSE-command is rejected as soon as one of the protective elements in the relay
picks up. The OPEN-command, in contrast, can always be executed. Please be aware, activation of thermal
overload protection elements or sensitive ground fault detection can create and maintain a fault condition
status, and can therefore block CLOSE commands. If the interlocking is removed, consider that, on the other
hand, the restart inhibit for motors will not automatically reject a CLOSE command to the motor. Restarting
would then have to be interlocked in some other way. One method would be to use a specific interlocking in
the CFC logic.
• Double Operation Block: Parallel switching operations are interlocked; while one switching operation is
being processed a second one can be executed.
• Switching Authority LOCAL: A switching command of the local control (command with command source
LOCAL) is only allowed if a LOCAL control is allowed at the device (by configuration).
• Switching Authority DIGSI: Switching commands that are issued locally or remotely via DIGSI (command
with command source DIGSI) are only allowed if remote control is admissible for the device (by configura-
tion). If a DIGSI PC connects to the device, it deposits here its virtual device (VD) number. Only commands
with this VD (when Switching Authority = REMOTE) will be accepted by the device. Remote switching com-
mands will be rejected.
• Switching Authority REMOTE: A switching control command (command with source of command REMOTE)
is only allowed if REMOTE control is admissible at the device (by configuration).
SIPROTEC, 7SJ61, Manual
C53000-G1140-C210-1, Release date 02.2008
Example of an operational annunciation for switching circuit breaker 52 (Q0)
Functions
2.18 Breaker Control
249