Co-Inverter Communication - Omron 3G3MX2 User Manual

6-7 Co-Inverter Communication

The 3G3MX2 provides the Co-inverter communication function to allow for communication
among multiple 3G3MX2 Inverters without using a PC, PLC or other master equipment, in
addition to performing normal Modbus communication (Modbus-RTU) (slave).
In Co-inverter communication, each Inverter plays the role of "Management Inverter", "Master
Inverter" or "Slave Inverter". For the Management Inverter, the Master Inverter as set by the user
is specified. All other Inverters become slave Inverters. Although the Management Inverter is
always fixed, the Master Inverter changes sequentially. Accordingly, the Management Inverter
may be the Master Inverter or Slave Inverter. Other conditions are specified below:
One Management Inverter is required within the network.
Up to eight Inverters can be selected that function as the Master Inverter.
Up to 247 Inverters (or 32 Inverters without repeater, regulated by the RS-485 network) can be
connected across the network.
Station No. 1 operates as the Management Inverter in Co-inverter communication. Accordingly,
be sure to provide a Management Inverter of Station No. 1.
The Master Inverter can write data into holding registers in a given Slave Inverter. Up to five
different station numbers and holding registers can be specified at a time. When one data
transmission is completed between the master and slave, the Master Inverter changes
sequentially and data transmission is repeated according to the details set for each Master
Inverter.
Management Inverter
(01)
: Master Inverter
*1. The Master Inverter is switched automatically by the Management Inverter.
*2. A command to switch the Master Inverter from 01 to 02 is sent after an elapse of the silent interval +
Communication Wait Time (C078), following the data transmission from the Inverter 01 master to the
slave.
*3. Upon receiving the data sent from the Master Inverter, the Management Inverter sends the next
master switching command after an elapse of the silent interval + Communication Wait Time (C078).
If the data sent from the Master Inverter could not be received within the Communication Error Timeout
SYSDRIVE MX2 Series USER'S MANUAL (3G3MX2-A@@@@)
Inverter (02) Inverter (03)

6-7 Co-Inverter Communication

Inverter (04)
Data transmission from the Inverter 01
master to the slave
Switch the Master Inverter from 01
to 02 *1, *2
Data transmission from the Inverter 02
master to the slave
Switch the Master Inverter from 02
to 03 *3, *4
Data transmission from the Inverter 03
master to the slave
Switch the Master Inverter from 03 to 04
Data transmission from the Inverter 04
master to the slave
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