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6. RS-485
In this chapter we explain the RS-485 functions of the TD-SC1 (485).
6-1. RS-485 overview
Format: RS-485 two-wire type
Transmission format: start-stop synchronization, half-duplex
transmission
Number of connected units: 32 maximum (including master)
Code: ASCII
6-2. Connections
6-2-1. RS-485 terminals
USB/RS-485 switch
RS-485 terminals
Signal name
Explanation
A+
Data (not reversed)
B−
Data (reversed)
TRM
Terminator
(by shorting B− and TRM, it can be used as a
terminator (110 Ω)
SG
Connection line
6-2-2. Inserting and removing RS-485
terminal bank
o
You can remove the terminal bank from the main unit by
loosening the two black screws at the ends of the terminal
bank and pulling it out.
o
Always disconnect the power before removing or installing
a terminal bank.
6-2-3. Connecting the RS-485 terminals
o
We recommend using twisted-pair cables for connections.
o
If these units will be used at both ends, short the B- and
TRM terminals. (This will enable termination.)
o
Always disconnect the power before working with wiring.
o
The recommended torque for the RS-485 terminal screws
and attachment screws is 0.69 N·m ≈ 7 kgf·cm.
o
After wiring, attach the terminal bank cover.
CAUTION
For the RS-485 connector, use the included KEC-NS0604-02.
Do not use any other connector because doing so could make
it unsafe.
6-2-4. Selecting RS-485 transmission
To use this unit with RS-485 for transmission, slide the USB/
RS-485 switch up.
o
Always disconnect the power before moving the switch.
