Individual Functions; Using Memobus Communications; Communications Specifications - YASKAWA Varispeed CIMR-G7A Instruction Manual

Individual Functions

This section explains the individual functions used in special applications.

Using MEMOBUS Communications

You can perform serial communications with MEMOCON-series Programmable Controllers (PLCs) or simi-
lar devices using the MEMOBUS protocol.
MEMOBUS Communications Configuration
MEMOBUS communications are configured using 1 master (PLC) and a maximum of 31 slaves. Serial com-
munications between master and slave are normally started by the master, and the slave responds.
The master performs signal communications with one slave at a time. Consequently, you must set the address
of each slave beforehand, so the master can perform signal communications using that address. Slaves receiv-
ing commands from the master perform the specified function, and send a response to the master.
RS-485
example
Fig 6.56 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
MEMOCON-series PLC
Inverter
connections
RS-422, RS-485
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 fixed
MEMOBUS (RTU mode only)
31 units max. (when using RS-485)
Inverter Inverter
Specifications
Individual Functions
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