BECKHOFF EP9128 - Manual (Page 20)

Basic functioin principles
Note
Connection to the EtherCAT Master
The connection to the EtherCAT Master resp. in the direction of the Master has to be done
on port 1! All other ports can be used for outgoing EtherCAT traffic. No special sequence is
required.
Topological configuration
With the EP9128, special attention should be paid to the sequence of the EtherCAT slaves. Since the
EP9128 has seven junction ports, drop lines connected to ports must and can be clearly identified in
practice. If incorrect information is provided in the configuration (TwinCAT System Manager file *.tsm), the
system cannot start.
For each EtherCAT device the System Manager indicates at which PreviousPort it is connected, i.e. the
name of the connected port (B to D) of the previous slave. This also applies for the internal connections
between the ESCs in the EP9128:
Fig. 16: Previous port of the second ESC in the EP9128
The Fig. above shows a topology as an example, with
• EP1018­0002 at port 2
• EP7041­3002 at port 3
• EP3314­002 at port 4
• EP3744­0041 at port 5
• EP2624­0002 at port 6
• EP2008­0001 at port 7 and
• EP5151­0002 at port 8
EP9128 20 Version 2.1.0