38 Device Description
WAGO I/O SYSTEM 750 XTR
750-8202/040-001 PFC200 2ETH RS TELE XTR
Manual
Version 1.2.0, valid from FW Version 03.01.07(13)
3.3.6.2 Operating as an RS-485 Interface
To minimize reflection at the end of the line, the RS-485 line must be terminated
at both ends by a cable termination. If required, one pull-up or pull-down resistor
may be used. These resistors ensure a defined level on the bus when no
subscriber is active, i.e., when all subscribers are in “Tri-state”.
Attention — bus termination!
The RS-485 bus must be terminated at both ends!
No more than two terminations per bus segment may be used!
Terminations may not be used in stub and branch lines!
Drop cables must be kept as short as possible!
Operation without proper termination of the RS-485 network may result in
transmission errors.
Figure 11: RS-485 Bus Termination
