Omron CS1W-SCU21 Operation Manual page 378

K3T# Intelligent Signal Processor Protocol
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Serial Communications
Board/Unit
*1: Set the 2-/4-wire switch
to the 2-wire setting.
*2: Turn ON the terminat-
ing resistance switch.
Note 1. The connection configuration is a one-to-one or a 1-to-N configuration. For 1-to-N connections, up to
32 units including the Serial Communications Boards/Units can be connected.
2. The maximum cable length is 500 m. Use shielded twisted-pair cables (AWG28i or greater).
3. Connect terminating resistance at both ends of the transmission path.
4. Turn the terminal block switch ON at the terminators.
5. Turn the terminal block switches OFF for units that are not terminators.
Signal name
Inverting output
Non-inverting output
Intelligent Signal Processor
Turn ON the terminal block switch for
terminators only.
RS-485: D-sub
9-pin female
RS-485:
Signal Pin
Terminal block
Name
No.
Termi-
FG
nal.
1
SDA
19
2
SDB
18
Shield
Shield
Abbreviation
–
+
51 kΩ
Terminal
block SW
220 Ω
Signal
Name
4.7 kΩ
4.7 kΩ
6.8 V
Intelligent Signal Processor
Unit designated as terminator.
RS-485:
Terminal block
Signal
Terminal block SW ON
Termi- 220 Ω
nal. Name
18
19
The terminal block switch is turned ON.
Signal direction
Input or output
Input or output
SN751177N or
equivalent
5 V
TX
RX
4.7 kΩ
Appendix I
Terminal
19
18
359