Siemens SITRANS FC410, Руководство по эксплуатации, Страница: 44 / 160

Connecting
5.4 Connecting the FC410
FC410 with Modbus
42
Operating Instructions, 02/2016, A5E33120874-AC
5.4.3 Setting the EOL termination DIP switches
It is important to terminate the Modbus RS 485 line correctly at the start and end of the bus
segment since impedance mismatch results in reflections on the line which can cause faulty
communication transmission.
If the device is at the end of the bus segment, it is recommended to terminate the device as
shown in System configurations (Page 43). The table below shows the relation between the
DIP switch settings and the permissible communication interface set-ups. Default
configuration is EOL active.
Location of DIP switch
The DIP switch is located in the electronic as shown below.
Image 5-3 DIP switch location (all set to ON)
DIP switch settings for communication set-up
DIP switch Communi-
cation set-up
Switch 1 Switch 2 Switch 3 Switch 4
EOL active On On On On
EOL not active On On Off Off
NOTICE
Avoid DIP switch settings not mentioned in the table!
DIP switch settings not mentioned in the table above are not allowed and may reduce
communication interface reliability.
See also
System integration (Page 23)