ABB REL650 Applications Manual page 345

1MRK 506 334-UUS A
Application manual
Switch controller (SCSWI)
The Switch controller (SCSWI) initializes and supervises all functions to properly select
and operate switching primary apparatuses. The Switch controller may handle and operate
on one three-phase device.
After the selection of an apparatus and before the execution, the switch controller
performs the following checks and actions:
• A request initiates to reserve other bays to prevent simultaneous operation.
• Actual position inputs for interlocking information are read and evaluated if the
operation is permitted.
• The synchronism check/synchronizing conditions are read and checked, and
performs operation upon positive response.
• The blocking conditions are evaluated
• The position indications are evaluated according to given command and its requested
direction (open or closed).
The command sequence is supervised regarding the time between:
• Select and execute.
• Select and until the reservation is granted.
• Execute and the final end position of the apparatus.
• Execute and valid close conditions from the synchronism check.
At error the command sequence is cancelled.
The mid position of apparatuses can be suppressed at SCSWI by setting the tIntermediate
at (SXCBR/SXSWI) to an appropriate value.
The switch controller is not dependent on the type of switching device SXCBR or SXSWI.
The switch controller represents the content of the SCSWI logical node (according to IEC
61850) with mandatory functionality.
Reservation function (SELGGIO)
The purpose of the reservation function is to grant permission to operate only one device
at a time in a group, like a bay or a station, thereby preventing double operation.
For interlocking evaluation in a substation, the position information from switching
devices, such as circuit breakers, disconnectors and grounding switches can be required
from the same bay or from several other bays. When information is needed from other
bays, it is exchanged over the serial station bus between the distributed IEDs. The problem
that arises, even at a high speed of communication, is a time interval during which the
information about the position of the switching devices are uncertain. The interlocking
function uses this information for evaluation, which means that also the interlocking
conditions will be uncertain.
Section 11
Control
339