A complete guide to Modbus — the most widely deployed industrial communication protocol — covering RTU vs. TCP differences, register types, function codes, and how to use Modbus in modern SCADA systems.
Modbus is a serial communication protocol developed by Modicon in 1979 for use with its PLCs. Despite its age, Modbus remains one of the most widely deployed protocols in industrial automation and SCADA systems worldwide — found in PLCs, VFDs, power meters, flow meters, RTUs, and countless field devices. Its longevity comes from its simplicity: Modbus is easy to implement, royalty-free, and supported by virtually every industrial device manufacturer.
Topics covered
SCADA/ICS System Architecture — Extended Practice Exam
✨ Premium ContentGo beyond the free practice questions with a full-length paid exam bank.
Industrial Controls Project — Start to Finish (Full Access)
✨ Premium ContentA structured, paid professional training program for this discipline.
PLC Programming, Wiring, Process Control & Instrumentation — Illustrated Guide (Full Access)
✨ Premium ContentA zoomable interactive reader — free preview, then unlock the full set.
PLC Ladder Logic Programming: A Practical Guide for Beginners
✨ Premium ContentA paid interactive calculator or 3D simulator for this discipline — part of the All-Access Pass.
📬 Get new engineering guides in your inbox
New calculators, interactive readers, and reference guides — no spam, unsubscribe anytime.
Put this knowledge to work on your iPhone
Browse our full catalog of professional iOS apps — from electrical code tools to AI builders.
Browse All 95+ Apps