ABB REG670 - Page 651

The open or closed positions of the HV apparatuses are inputs to software modules
distributed in the control IEDs. Each module contains the interlocking logic for a bay.
The interlocking logic in a module is different, depending on the bay function and the
switchyard arrangements, that is, double-breaker or 1 1/2 breaker bays have different
modules. Specific interlocking conditions and connections between standard
interlocking modules are performed with an engineering tool. Bay-level interlocking
signals can include the following kind of information:
• Positions of HV apparatuses (sometimes per phase)
• Valid positions (if evaluated in the control module)
• External release (to add special conditions for release)
• Line voltage (to block operation of line earthing switch)
• Output signals to release the HV apparatus
The interlocking module is connected to the surrounding functions within a bay as
shown in figure
305.
Interlocking
modules in
other bays
Interlocking
module
SCILO SCSWI
Apparatus control
modules
SXCBR
SCILO SCSWI
SXSWI
Apparatus control
modules
SCILO SCSWI
SXSWI
Apparatus control
modules
en04000526.vsd
IEC04000526 V1 EN
Figure 305: Interlocking module on bay level
Bays communicate via the station bus and can convey information regarding the
following:
• Unearthed busbars
• Busbars connected together
• Other bays connected to a busbar
• Received data from other bays is valid
Figure
306 illustrates the data exchange principle.
1MRK502052-UEN B Section 14
Control
645
Technical manual