Zone Selective Interlocking
5.2 Examples
3WL/3VL circuit breakers with communication capability - PROFIBUS
114
System Manual, 03/2011, A5E01051353-02
5.2.2.5
Coupling switch
Wiring example of 3 grading levels with coupling switch
=6,
PRG
XOH
=6,
PRG
XOH
=6,
PRG
XOH
=6,
PRG
XOH
=6,PRGXOH
6(17521:/
6(17521:/
6(17521:/
6(17521:/
6(17521:/
The TIE BRKR function (X4-1, 2) ensures that the ZSI IN signal (3, 4) is immediately
forwarded to the output ZSI OUT (5, 6) even if the coupling switch is switched off. Without
the TIE BRKR function, the ZSI signal would not be forwarded.
The coupling switch is a separate grading level and receives its own delay time t
sd
.