Sutron P Line, User Manual

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Interfaces of the Device P Line Touch Panel
50
4.3.1.2 Termination
Always turn on the termination in a 4-wire point-to-point connection (RS-422 / RS-
485). A sender termination for the quiescent level of the receiver must exist on the
remote station.
Turn on the termination only at the two ends of the lines in a 2 or 4-wire multi-point
connection (RS-422 / RS-485).
Figure 4-5 Termination possibilities RS-422 / RS-485 (intern)
Table 4-4 Resistance values termination RS-422 / RS-485
Designation Value
R1 120 Ohm
The switch positions for ON or OFF are printed onto the operating device. Only
the specified switch positions are allowed.
Table 4-5 Termination switch RS-422 / RS-485
Switch position Function
ON Receiver termination
(120 Ohm)
OFF No receiver termination