Modbus is a serial communication protocol on the application layer used to transmit data between electronic devices used in the industrial automation and control industry. Wireless Modbus provides an added layer enabling Modbus devices to transmit information wirelessly. This can be designed for any type of Modbus including two of the most common options – TCP/IP and RTU. RS485 is a standard defining the electrical characteristics of drivers and receivers for use in serial communication systems. This standard is commonly used in commercial buildings and industrial environment for energy management and building automation applications because it can be used effectively over long distance and electrically noisy environments. RS485 standard is often used in a master-slave arrangement- when one device, the master, initiates all communications activity, and controls the slave devices connected to it.
DifferenceModbus RTU (RS495 and RS232) is still the most commonly used implementation in industrial automation due to cost and practicality. It uses a Master/Slave configuration to communicate between devices. Master devices such as DAQs poll field sensors and meters by sending a request to receive a status response at regular intervals. Modbus RTU does this through a serial communication protocol that sends binary data (1 and 0) sequentially from the master and slave. Slave devices do not communicate with other slave devices. Modbus TCP/IP runs on the Ethernet over the TCP interface transport layer utilizing the improvements in speed and number of connected devices. Ethernet, unlike serial communication, sends data via packets over a TCP/IP network.
- Support for multiple Modbus options – RTU and TCP/IP
- Simultaneous support for Ethernet, RS485 and RS232
- Easier to install, maintain and update
- Trouble-shoot issues remotely