User`s manual

19
FX3U Series Programmable Controllers
User’s Manual - MODBUS Serial Communication Edition
3 System Configuration
3.3 Limitation when Channel 1 and Channel 2 are used at the
1
Outline
2
Specifications
3
System Configuration
4
Wiring
5
Communication Setup
6
Related Devices and Comm. Status
7
MODBUS Standard Commands
8
Master Specification
9
Slave Specification
10
Creating Programs
3.3 Limitation when Channel 1 and Channel 2 are used at the same time
When using Channel 1 (ch1) and Channel 2 (ch2) at the same time, the available communication type
combinations are limited. For more details, refer to the table below.
*1. Ch2 cannot be set for non-protocol communication using the RS instruction.
*2. When using remote maintenance on ch2, use GX Developer Ver. 8.18U or later.
Example1:
When using "MODBUS Serial Communication" on ch1, "MODBUS Serial Communication" can not be set on
ch2.
Example2:
When using "MODBUS Serial Communication" on ch1, "N:N Networking" can be used on ch2.
→ For more details on using N:N Networking and MODBUS Serial Communication, refer to Section
5.3.
Communication Setting on Ch1
MODBUS
Serial Com-
munication
N:N
Networking
Parallel Link
Computer
Link
Inverter Com-
munication
Non-protocol
Communica-
tion (RS
instruction)
Non-protocol
Communica-
tion (RS2
instruction)
Programming
Communica-
tion
Remote
Maintenance
Communication Setting on Ch2
*1
MODBUS Serial
Communication
-
(Example 1)
33333333
N:N Networking
3
(Example 2)
--333333
Parallel Link
3 --333333
Computer Link
333333333
Inverter
Communication
333333333
Non-protocol
Communication
(RS2 instruction)
333333333
Programming
Communication
333333333
Remote
Maintenance
*2
33333333
-
3: Applicable
-: Not applicable
RD
RDA
RDB
SDA
SDB
SG
SD
Communication channel: ch1
Expansion
board
FX
3U PLC
Communication
channel: ch2
Communication
special adapter
Communication
special adapter