ABB C250 User manual - 3.1
6
Notes.
•
Programmable baud rate – 2400 or 9600 baud.
•
Selectable parity – odd, even or none.
•
Address range – 1 to 99.
For MODBUS communications to operate correctly, each COMMANDER 250/V250
must be configured with the correct serial transmission parameters and assigned a
unique address.
3.1
Accessing the Configuration Mode
To access the Configuration Mode, set the security switch to the ‘Configure’ position,
as shown in Fig. 4.1 of the relevant
User Guide.
When all parameters have been
programmed, reset the switch to the ‘Normal’ position.
3.2
Setting the Serial Transmission Parameters – Fig. 3.1
Fig. 3.1 shows the display readouts and options available when defining the serial
transmission rate and bit parity for COMMANDER 250 and V250 instruments. Further
detail on the procedure required to set each parameter are shown in Section 4.3.4 of
the relevant
User Guide.
3.3
Setting the MODBUS Address
To allow the master to differentiate between more than one slave in a system, each
slave on a MODBUS link must be assigned a unique address in the range 1 to 99. See
section 4.4 of the relevant
User Guide
(MODBUS Address Frame,
Addr
).
3
CONFIGURATION
Fig. 3.1 Setting Serial Transmission Parameters
PrS
t
210
0
S – Serial Communication Configuration
T – Serial Communications Parity
C250/V250
C250/V250
Display
Baud Rate, 2/4-wire
0
Off
1
2400, 2-wire
2
2400, 4-wire
3
9600, 2-wire
4
9600, 4-wire
Pr
S
t
21
0
0
Display
Parity
0
None
1
Odd
2
Even