I am having a Honeywell DCS c300. I want to interface it to a Modicon m340 or tm221. I am a beginner. Anyone give some help?
Talk with whomever is in charge of your dcs and see if this capability already exists. If not, this person can arrange to purchase it from Honeywell.
It depends what you are trying to do, and what the functionality and logic required is.
There are atleast 2 ways to do it.
1-via SCADA tags, you setup a controller, channel and points in SCADA to access the PLC.
SCADA is good for indication, alarms, operator commands and feedback.
2-If you want C300 controller direct access to PLC points, then you can use the FTE ethernet via a firewall to talk ModBus TCP to the PLC.
"The C300 Controller supports peer control data interface (PCDI) for peer device data exchange for process control. The PCDI communicates with Safety Manager and other Analyzers and Programmable Logic Controllers (PLCs) that support the MODBUS TCP protocol, including a serial MODBUS protocol through an off the shelf MODBUS TCP Bridge, over Experion LX's Fault Tolerant Ethernet (FTE) network."