3-3
3.2 Procedure of the recording data from slave devices
This section describes the procedures from connecting to slave devices until displaying screens and
recording data, using the Modbus master function of this device. Note that some of the procedures
can be done only using the parameter loader.
Item
Description
Slave Main
unit Loader
Remarks
1
Check the communication specifications of the
slave devices and make settings so that each
device has the same setting.
- Communication speed.
- Parity
- Stop bit
Yes
-
-
2
Wiring
Carry out wiring for the RS-485 communications
following the manuals of the slave devices and the
description about wiring of the main unit.
3
Set the slave devices' IDs (station numbers).
Each slave device must have a unique ID number
other than 0.
Yes
-
-
4
From the Modbus maps of the slave devices,
check the address of the data to be obtained.
Yes
-
-
The data which can be
acquired are the input register
(FuncCode=04H) and
the hold register
(FuncCode=03H).
Other coils such as bit data
can not be acquired.
5
Enable "Remote AI"
on the engineering settings.
Main unit: MENU button > System key >
Engineering key > Remote AI key
Loader: Display > Engineering
-
Yes
Yes See section 3.3.
6
Set the communication settings of this device.
- Communication speed.
- Parity
- Stop bit
Main unit: MENU button > System key> Comm.
key > Modbus1 key
Loader: Communication setting 2
-
Yes
Yes See section 3.4.
7
Carry out the Modbus settings.
-
Modbus communication type ...
"MoRTU"
- Master/slave ... Master mode (General-purpose)
- Auto retry
- Acquisition interval
Main unit: MENU button > System key > Comm.
key > Modbus2 key
Loader: Communication setting 2
-
Yes
Yes See section 3.5.
After the settings are
completed, the main unit must
be rebooted.
8
Carry out the Modbus mater settings (for
connecting with slave devices).
Up to 12 types of settings are enabled.
- Communication ID
- Slave ID
- Address
- Register type
- Type
- Decimal point position
- Number of data
-
Yes
Yes See section 3.6.
