Communication Protocol
When selecting a communication protocol for industrial applications, various factors must be taken into account. One major challenge is the large number of protocols used by different manufacturers, which are often not compatible.
Key Selection Criteria:
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Use of a simple, universal, stable, and interference-resistant communication protocol that is already being used successfully in the industry.
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Widely used by almost all manufacturers for the myriad of PLCs, VFDs, HMIs, meters, and sensors available on the market.
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Compatibility problems should be avoided, and the integration of devices from different manufacturers should be facilitated.
For this reason, Modbus TCP was chosen for the development of the DO-1. Sensors and devices can be connected in series in a network, which is very popular for industrial control networks. The Modbus RTU communication protocol provides reliable and efficient communication over a 2-wire serial connection (RS485) . This connection is easy to set up and maintain, making it a suitable option for use with sensors and data acquisition devices.
Modbus TCP
Modbus TCP is an Ethernet extension of Modbus. If a local Ethernet network (LAN) already exists, the Modbus TCP communication protocol can be used to connect sensors and data acquisition devices that have an Ethernet port. If sensors and data acquisition devices only have a 2-wire serial connection, they can still be connected using a suitable RS-485 serial converter. This allows seamless integration into an existing network and provides greater installation flexibility.
This figure shows an example for a Modbus RTU / TCP network.
PIC TO BE ADDED