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

FX Series PLC User's Manual - Data Communication Edition
Inverter Communication
4.5

Connecting Terminal Resistors

Connect a terminal resistor to both the communication equipment of the FX PLC and the RDA-RDB signal
terminal in the last inverter.
1. Terminal resistor types
Prepare the following two types of terminal resistors.
Among the terminal resistors supplied with the communication equipment,
select ones with the color codes shown to the right.
1) On the FX PLC side, use a terminal resistor of 110 , 1/2 W supplied
together with the communication equipment operating in accordance with
RS-485.
2) On the inverter side (PU connector except FR-A5NR, FR-E7TR), use a
terminal resistor of 100 , 1/2 W (not supplied).
3) On the inverter side (FR-A5NR), use a terminal resistor chip (supplied
together with the FR-A5NR).
4) On the inverter side (FR-E7TR), use the terminal resistor switch.
2. Connecting a terminal resistor to the FX PLC
Connect a terminal resistor between the RDA and RDB terminals of the communication equipment.
3. When using the FX
The FX -485-BD, FX
3G
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
E-32
-485-BD, FX
3U 3G
-485-BD, FX
3U 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
For details on connection, refer to each wiring diagram.
-485-BD, FX -485-BD-RJ or FX
3G
-485-BD-RJ and FX -485ADP(-MB) have built-in terminal resistors.
3U
• FX
Terminal
resistor
selector
switch
Model name
SZS 0.4  2.5
4.5 Connecting Terminal Resistors
Brown
1 1 1
(10
Brown Black
1 0 1
(10
-485ADP(-MB)
3U
-485ADP(-MB)
3U
330 
OPEN
110 
-485-BD.
3G
0.4mm
(0.01")
4 Wiring
Precision
=110 
1 )
Brown Precision
=100 
1 )
Terminal
resistor selector
switch
Select a
screwdriver
with a
straight tip.
2.5mm
(0.09")