Siemens SIPROTEC 7SC80 Series Manual page 178

Functions
2.15 Command Processing
The "plus" appearing in the message is a confirmation of the command execution. The command execution
was as expected, in other words positive. The minus sign means a negative confirmation, the command was
rejected. Possible command feedbacks and their causes are dealt with in the SIPROTEC 4 System Descrip-
tion. The following figure shows operational indications relating to command execution and operation response
information for successful switching of the circuit breaker.
The check of interlocking can be programmed separately for all switching devices and tags that were set with
a tagging command. Other internal commands such as manual entry or abort are not checked, i.e. carried out
independent of the interlocking.
Figure 2-46 Example of an operational annunciation for switching circuit breaker 52 (Q0)
Standard Interlocking (default)
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.) This condition is checked in both interlocked and non-in-
terlocked status modes.
• System Interlocking: To check the power 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.
• Protection blocking: Switch-ON commands are rejected in the case of interlocked switches as soon as one
of the protection functions of the unit has initiated a trip log. However, trip commands can always be execut-
ed.
• Double Operation Block: Parallel switching operations are interlocked against one another; while one
command is processed, a second cannot be carried out.
• Switching Authority LOCAL: A control command from the user interface of the device (command with
command source LOCAL) is only allowed if the Key Switch (for devices without key switch via configuration)
is set to LOCAL.
• Switching authority DIGSI: Switching commands that are issued locally or remotely via DIGSI (command
with source DIGSI) are only allowed if remote control is enabled at the device (by configuration). If a DIGSI
computer logs on to the device, it leaves a Virtual Device Number (VD). Only commands with this VD (when
switching authority = REMOTE) are accepted by the device. Remote switching commands are rejected.
• Switching authority REMOTE: A remote switching command (command with source REMOTE) is only
allowed if remote control is enabled at the device (by configuration).
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SIPROTEC, 7SC80, Manual
E50417-G1140-C486-A1, Release date 12.2011