Siemens siprotec SJ62 User Manual page 357

2 Functions
Standard Interlock-
ing Defaults (fixed
programming)
355
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 Description. The following
figure shows operational indications relating to command execution and operation re-
sponse 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 2-124 Example of an operational annunciation for switching circuit breaker 52 (Q0)
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 activat-
ed or deactivated.) This condition is checked in both interlocked and non-inter-
locked 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.
• Blocked by Protection: A CLOSE-command is rejected as soon as one of the pro-
tective 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 some
other way. One method would be to use a specific interlocking in the CFC logic.
• 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.
SIPROTEC 4, 7SJ62/63/64 Handbuch
C53000-G1140-C147-A, Edition 07.2015