Phoenix Contact UM EN TP 3 Series, User Manual

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TP 3057M, TP 3057T, TP 3070T, TP 3105T, TP 3121T
4-6
PHOENIX CONTACT 8095_en_00
4.2.1.2 Termination
For point-to-point connections, always activate the termination. For multi-point connections,
only activate the termination at the cable end.
Figure 4-5 Block diagram termination RS485
Legend for table:
I = Switch ON
- = Switch OFF
Table 4-4 Resistance values termination RS485
Designation Value
R1, R3 510 Ohm
R2 150 Ohm
R4 120 Ohm
NOTICE
The switch positions for ON or OFF are printed onto the termination switch. Only the spec-
ified switch positions are allowed.
Table 4-5 Termination switch
S1 S2 S3 S4 Function
Transmitter Receiver
I I I I Termination is ON
– – – – Termination is OFF