Individual Functions; Using Memobus Communications - Omron VARISPEED E7 User Manual

Individual Functions

Using MEMOBUS Communications

The Varispeed E7 is equipped with a RS422/485 serial communication port using the MEMOBUS protocol
MEMOBUS Communication Configuration
MEMOBUS enables a master device (e.g. PLC) to communicate with up to 31 slave devices (e.g. Inverters).
Basically the slaves respond on messages sent from the master.
The master performs serial communications with only one slave at a time. Consequently, to every slave a
address must be assigned.
Fig 6.50 Example of Connections between PLC and Inverter
Communications Specifications
The MEMOBUS communications specifications are shown in the following table.
Item
Interface
Communications Cycle
Communications Parameters
Communications Protocol
Number of Connectable Units
PLC
Inverter
RS422, RS485
Asynchronous (Start-stop synchronization)
Baud rate: Select from 1,200, 2,400, 4,800, 9,600 and 19,200 bps.
Data length: 8 bits fixed
Parity: Select from even, odd or none.
Stop bits: 1 bit selected
MEMOBUS
31 units max.
Inverter Inverter
Specifications

Individual Functions

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