Appendix C Multi-Link Connection This chapter describes the connecting methods used to connect multiple HMIs to one or mor
external controllers, i.e. PLCs.
The connecting method for multi-link connection is shown as the figure below. The Ethernet
and COM2 serial port of HMIs are used.
HMI 1
172.16.190.1
HMI 3
172.16.190.3
Ethernet
COM2 / RS-485
HMI 2 reads the data of
PLC 1 via Ethernet
HMI 3 reads the data of
PLC 1 via Ethernet
Ethernet
PLC 1
HMI 2
172.16.190.2
In the figure above, three HMIs, HMI 1, HMI 2 and HMI 3 are connected via Ethernet.
Only HMI 1is connected to PLC 1 by using COM2 serial port through RS-485 communication.
HMI 2 and HMI 3 are not connected to any external controller. However, through 1:N connection,
HMI 2 and HMI 3 are able to access the registers of PLC 1 via Etherent.
Revision May, 2010 C-1