Common industrial network protocol – Modbus
Modbus is an open protocol that can be used by any manufacturer or vendor without restriction. It was originally designed in the mid-1970s by Modicon as a way to connect intelligent devices with PLCs using a simple master/slave concept. It was initially designed for Modicon PLCs only (that is, a proprietary protocol) but it was later made available for use by any manufacturer without any restriction (that is, an open protocol).
Various vendors now manufacture their PLCs and other industrial devices to support the Modbus protocol. Hence, you will find the Modbus protocol available for use in industrial equipment from various manufacturers, such as Siemens, Allen Bradly, Mitsubishi, and Omron. The Modbus protocol solves the problem of communication between industrial equipment from different manufacturers. With the Modbus protocol, a Siemens PLC can communicate with an Omron PLC, Allen Bradley PLC, Omron VFD, or any other industrial...