What is Modbus?
The Modbus communications protocol is the granddaddy of the networking industry and is still the only open-source electronic networking protocol for connecting automation systems. Modbus was released in 1979 and is still the most widely available protocol for connecting a wide range of industrial applications, including industrial automation, transportation, energy, and remote monitoring. Virtually any type of sensor and controller devices can be found that incorporate Modbus networking, including ICE engines and ECU controllers, PID controllers, discrete sensors, valves, programmable logic controllers (PLCs), and many other embedded devices.
Related Webinar: The Connected Workshop Framework for Industrial OEMs
What is Modbus Used For
In simple terms, Modbus is a method used for transmitting information over serial data lines between electronic devices. Modbus RTU uses RS-485 or RS-232 for serial data communications and is also popular for remote applications that communicate instrumentation and control devices back to a main controller or data gathering system, for example a system that measures temperature and humidity and communicates the results to a computer, over cellular telephone networks.
Modbus is often used to connect a supervisory computer with a remote terminal unit (RTU) in supervisory control and data acquisition (SCADA) systems. Versions of the Modbus protocol exist for serial lines (Modbus RTU) and for Ethernet (Modbus TCP).
CalAmp Supports ModBus in Industrial Telematics
CalAmp’s new HMU-3640LB, a ruggedized telematics gateway, natively supports RS-232 and RS-485 serial data. Using an EdgeApp application, our customers are using Modbus to verify maintenance, operational, and location telemetry for their industrial rental equipment clients.