Connecting Terminal Resistors - Mitsubishi Electric FX3U-232-BD User Manual

FX Series PLC User's Manual - Data Communication Edition
Parallel Link
4.2.5

Connecting terminal resistors

In the case of one-pair wiring, connect a terminal resistor to the RDA-RDB signal
terminal of the communication equipment.
In the case of two-pair wiring, connect a terminal resistor to the RDA-RDB signal
terminal and SDA-SDB terminal of the communication equipment.
1. Terminal resistor type
In the case of one-pair wiring, use two terminal resistors of 110 , 1/2 W.
In the case of two-pair wiring, use four terminal resistors of 330 , 1/4 W.
Among the terminal resistors supplied with the communication equipment, select
ones with the color codes shown to the right.
2. When using the FX
FX -485ADP(-MB)
3U
The FX -485-BD, FX
3U
have built-in terminal resistors.
Set the terminal resistor selector switch accordingly.
• FX -485-BD
3U
• FX -485-BD
3G
Remove the upper terminal block before changing over the switch in the FX
Removal: Loosen the terminal block mounting screws, and remove the terminal block.
Installation: Attach the terminal block, and tighten the terminal block mounting screws.
For installation and removal of the terminal block, use the
recommended tool shown below or a tool having straight tip (such as
screwdriver) as shown in the right figure.
<Reference>
Manufacturer
Phoenix Contact Co., Ltd.
Terminal block mounting screws
• FX -485-BD-RJ
3G
C-28
-485-BD, FX
3U 3G
-485-BD, FX
3G 3G
Tightening torque: 0.4 to 0.5 N•m
Do not tighten terminal screws with a torque outside the above-mentioned range. Failure to do
so may cause equipment failures or malfunctions.
Terminal resistor
selector switch
Terminal resistor
selector switch
-485-BD, FX -485-BD-RJ or
3G
-485-BD-RJ and FX -485ADP(-MB)
3U
• FX
Terminal
resistor
selector
switch
Model name
SZS 0.4  2.5
4.2 Selecting Cables and Terminal Resistors
Brown
1 1 1
Orange Brown
3 3 1
-485ADP(-MB)
3U
330 
OPEN
110 
-485-BD.
3G
0.4mm
(0.01")
4 Wiring
Precision
=110 
1
(10 )
Precision
=330 
1
(10 )
Terminal
resistor selector
switch
Select a
screwdriver
with a
straight tip.
2.5mm
(0.09")