Mitsubishi Electric LE7-40GU, Instruction Manual, Page: 92 / 154

90
6 N:N NETWORK
6.3 Communication Setting
Connection diagram
Use single pair wiring for N:N Network wiring.
*1 Be sure to apply Class D grounding to the shield of the twisted pair cable to be connected.
*2 Terminal resistor should be attached to both ends of the line. LE7-40GU, the built-in RS-485 port of the CPU module, FX5-485-BD, and
FX5-485ADP, have built-in terminating resistors. Set the terminal resistor with the selector.
Grounding
Grounding should be performed as stated below.
• Perform Class D grounding. (Ground resistance: 100

or less)
• Independent grounding should be performed for best results.
• When independent grounding cannot be performed, perform "shared grounding" as shown in the following figure.
The grounding wire size should be AWG 24 to 16 (cross-section area: 0.2 to 1.5 mm
2
).
The grounding point should be close to the tension controller, and all grounding wires should be as short as possible.
6.3
Communication Setting
Communication specifications
The communication specification of the N:N Network is as follows.
Communication specifications
Item Specifications
Transmission standard Conforms to RS-485 standard
Maximum transmission distance 50 m
Communication method Bidirectional half-duplex
Wiring method One-pair wiring
Communication procedure N:N Network (pattern 2 only)
Transmission speed (baud rate) N:N Network: 38,400 (bps)
Insulation Non-isolated (between the communication line and CPU)
CPU module built-in RS-485 port
FX5-485-BD
FX5-485ADP
SDA
SDB
RDA
RDB
SG
Termination
Resistance
110

*2
Termination
Resistance
110

*2
SDA
SDB
RDA
RDB
SG
SDA
SDB
RDA
RDB
SG
SDA
SDB
RDA
RDB
SG
LE7-40GU LE7-40GU LE7-40GU
*1
Class D grounding
(Ground resistance:
100

or less) *1
Class D grounding
(Ground resistance:
100

or less) *1
Class D grounding
(Ground resistance:
100

or less)
Independent grounding
(Best)
Shared grounding
(Good)
Common grounding
(Not allowed)
Tension
Controller
Tension
Controller
Tension
Controller
Other
equipment
Other
equipment
Other
equipment