Functions
2.27 Command Processing
SIPROTEC, 7SD5, Manual
C53000-G1176-C169-5, Release date 02.2011
487
2.27.1.2 Sequence in the Command Path
Safety mechanisms in the command sequence ensure that a switch command can only be released after a
thorough check of preset criteria has been successfully concluded. Additionally, user-defined interlocking con-
ditions can be configured separately for each device. The actual execution of the command is also monitored
after its release. The entire sequence of a command is described briefly in the following list:
Checking a Command Path
Please observe the following:
• Command entry, e.g. using the keypad on the local user interface of the device
– Check password
→
access rights;
– Check switching mode (interlocking activated/deactivated)
→
selection of deactivated interlocking status.
• User configurable interlocking checks:
– Switching authority;
– Device position check (set vs. actual comparison);
– Zone controlled / bay interlocking (logic using CFC);
– System interlocking (centrally via SICAM);
– Double operation (interlocking against parallel switching operation);
– Protection blocking (blocking of switching operations by protection functions);
– Checking the synchronism before a close command.
• Fixed commands:
– Internal process time (software watch dog which checks the time for processing the control action
between initiation of the control and final close of the relay contact);
– Configuration in process (if setting modification is in process, commands are rejected or delayed);
– Equipment present as output;
– Output block (if an output block has been programmed for the circuit breaker, and is active at the moment
the command is processed, then the command is rejected);
– Component hardware malfunction;
– Command in progress (only one command can be processed at a time for each circuit breaker or switch);
– 1–of–n check (for multiple allocations such as common contact relays or multiple protection commands
configured to the same contact it is checked if a command procedure was already initiated for the output
relays concerned or if a protection command is present. Superimposed commands in the same switching
direction are tolerated).
Command Execution Monitoring
The following is monitored:
• Interruption of a command because of a cancel command,
• Running time monitor (feedback monitoring time).
