Technical FAQs

Ask a Question

Can the M580/M340 PLC read from Modbus Plus nodes through the M580/M340 Modbus Plus proxy?

 

Title
M580/M340 EGD Modbus Plus Proxy explicit communications.
 
Issue
To read from a remote Modbus Plus node, through the M580/M340 EGD Modbus Plus Proxy. a READ_VAR function block must be programmed in the logic of the M340 Unity program.
 
Product Line
Modicon M340 M580 PAC
 
Environment
Modicon M340, M580 PAC, Unity, TCSEGDB23F24FA
 
Cause
Ability to initiate explicit communications from a M580 or M340 PLC to a M580/M340 EGD Modbus Plus Proxy.
 
Resolution
The M580 or M340 can be programmed to direct a Read or Write_Var request through the M580/M340 EGD to read and write data to Modbus Plus nodes.
The Modbus Plus side of the Proxy can handle a maximum of four  READ_VAR or WRITE_VAR communications blocks at a time.
Attached below is an application example document with the details on how this is done.
Was this helpful?
What can we do to improve the information ?