Yaskawa iQpump Controller Programming Manual - Manual (Page 97)

YASKAWA TM.iQp.07 iQpump Controller Programming Manual 97
H5 Serial Communications Setup
This section explains the individual functions used in special applications involving MEMOBUS / Modbus Communications.
◆ Communication Specifications
The MEMOBUS / Modbus communication specifications are shown below:
Table 34 MEMOBUS / Modbus Communication Specifications
◆ MEMOBUS / Modbus Communication Configuration
MEMOBUS / Modbus communication is configured using 1 master (PLC) and a maximum of 31 slaves. Serial communication between
master and slave is normally initiated by the master and responded to by the slaves.
The master performs serial communication with one slave at a time. Consequently, the slave address of each slave must be individually
set, so that the master can perform serial communication using that address. Slaves receiving commands from the master perform the
specified functions, and send a response back to the master.
Figure 1.87
Figure 86. Example of Connections between Master and Drive
◆ Communication Connection Terminal
MEMOBUS / Modbus communication uses the following terminals: S+, S-, R+, and R-. The terminating resistance must be turned ON
only if the iQpump drive is at the very end of the Serial Communication chain. Set the terminating resistance by turning ON pin 1 of
switch S1 On the drives terminal board. Switch S1 is located directly above the left most relay module.
Figure 1.88
Figure 87. Communication Connection Terminals and Terminating Resistance
Item Specifications
Interface RS-422, RS-485
Communications Cycle Asynchronous (Start-stop synchronization)
Communications Parameters
Baud rate: Select from 1200, 2400, 4800, 9600, and 19200 bps.
Data length: 8 bits fixed
Parity: Select from even, odd, or none.
Stop bits: 1 bit selected
Communications Protocol MEMOBUS / Modbus
Number of Connectable Units 31 units max.
Master
iQpump iQpump iQpump
Slaves
Terminating resistance (1/2W, 110 Ohms)
RS-422A
or RS-485
Switch
S1
O
F
F
1
Terminating
resistance on
DIP Switch S1 located on
terminal board.
2
1