User Manual For - CONTROLLER/DATA RECORDER MultiCon CMC-99/141
7.8.11.5. Application of Logical channel in the Modbus mode
See also:
Chapter 7.15. MODBUS
Task:
The task is to read the temperature of two
SLAVE
devices from the
register 1
, which
has a physical address assigned:
'1 '
and
'8'
.
Solution:
First, configure the device in the MASTER mode (like in
of Modbus protocol in MASTER mode
), then configure it as follows and connect the SLAVE
Fig. 7.75. Schematic diagram for SLAVE devices connected to MultiCon
In the first step you need to configure
Logical channels
which will read data from Slave
devices. To do this:
–
touch the screen and press the
Menu
button,
–
press the
Device configuration
button,
–
enter the
Logical channels
menu,
–
using the arrows in the top navigation bar, select any
logical channel
such as 1,
–
in the
Name
parameter write
Temperature 1
,
–
Mode
parameter set as
Modbus
,
–
Port
parameter set as
MB1 (MASTER)
,
–
SLAVE devices
parameter set as
Addr.1:“Temp. converter”
,
–
Device input
parameter set as
Inp.1:HR 1h,b0-15
that reads
Register 1h
from
SLAVE 1
device,
–
Scale
parameter set as
linear
; in this example we don't need scaling but it is the
only way to set the unit displayed on the screen,
–
enter the
Configure scaling
submenu:
•
in
Output unit
write
°C
,
•
in
Input value
parameter in the
Point 1
section write
0
,
136
Power supply
(depending on version)
1
2
8
5
6
7
3
4
SERVISE
+24V DC ±5%
(
I
max. = 200mA)
digital input
0/15..24V DC
RS-485
GND
GND
A+
B-
isolated
Master
Device
Slave device 1
Slave address: 1
Register: 1h
Register: 2h
Register: 3h
Baud rate: 9600 bit./sec.
Device name:Temp. converter
Registers:
Modbus settings:
Slave device 2
Slave address: 8
Register: 1h
Register: 2h
Register: 3h
Baud rate: 9600 bit./sec.
Device name:Temp. converter
Modbus settings:
Registers:
GND
B-
A+
Port MB1
