5.3 MEMOBUS/Modbus Communications
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YASKAWA ELECTRIC
SIEP C710617 05F YASKAWA AC Drive GA700 Technical Manual
Figure 5.4 Wiring Diagram for More than One Drive
Note:
Set DIP switch S2 to the ON position on the last drive of the MEMOBUS/Modbus communication network to enable the termination
resistor.
◆
MEMOBUS/Modbus Drive Operations
Drive parameters will apply to the settings when the drive is running during MEMOBUS/Modbus
communications. This section gives information about the available functions and their related parameters.
■
Executable Functions
A PLC can do these operations with MEMOBUS/Modbus communications. Parameter settings (except H5-xx) do
not have an effect on the availability of these operations.
•
Monitor the drive status and operate the drive
•
Set and view parameters
•
Reset a fault
•
Multi-function input setting (The input command from MEMOBUS/Modbus communications and MFDI
terminals (S1 to S8) are linked by a logical OR operation.)
■
Drive Control
Select the external command that sets the frequency references and motor run/stop with MEMOBUS/Modbus
communications. Use the information in
to set the parameters as specified by the application.
Table 5.3 Required Parameter Settings for Drive Control from MEMOBUS/Modbus
LOCAL Control Selected
No.
Name
Setting Value
External reference 1
b1-01
Frequency Reference Selection 1
2 [Memobus/Modbus
Communications]
b1-02
Run Command Selection 1
2 [Memobus/Modbus
Communications]
External reference 2
b1-15
Frequency Reference Selection 2
2 [Memobus/Modbus
Communications]
b1-16
Run Command Selection 2
2 [Memobus/Modbus
Communications]
For more information about operation mode selection, refer to
b1-01 [Frequency Reference Selection 1]
and
b1-02
[Run Command Selection 1]
. Refer to
H1-xx = 2 [MFDI Function Select = External Reference 1/2 Selection]
for
more information about external command.
◆
Communications Timing
To prevent overrun of the slave side, the master cannot send a message to the same drive for a selected length of
time.
To prevent overrun of the master side, the slave cannot send a response message to the master for a selected length
of time.