Zakaria El Intissar

I'm an automation and industrial computing engineer with 12 years of experience in power system automation, SCADA communication protocols, and electrical protection. I build tools and write guides for Modbus, DNP3, IEC 101/103/104, and IEC 61850 on ScadaProtocols.com to help engineers decode, analyze, and troubleshoot real industrial communication systems.

Author Archives: Zakaria El Intissar

What is DNP3 Protocol?

The DNP3 protocol — short for Distributed Network Protocol version 3 — is a robust and reliable communication standard primarily used in SCADA (Supervisory Control and Data Acquisition) systems. It was designed to enable efficient, secure, and interoperable communication between control systems (master stations) and remote field devices such as RTUs (Remote Terminal Units) and IEDs (Intelligent Electronic… Read More »

DNP3 vs. IEC 60870-5-101: Key Differences and Similarities in SCADA Protocols

When you have finished this study on the difference between DNP3 and IEC 60870, you should be able to distinguish and identify the similarities between the two communication protocols. Comparison between DNP3 and IEC 60870-5-101 DNP3 (Distributed Network Protocol 3) and IEC 60870-5-101 are two communication protocols widely used in the field of industrial control systems (ICS) automation… Read More »

Modbus vs DNP3: A Technical Comparison for SCADA Engineers

In industrial control and SCADA environments, the choice of communication protocol determines system reliability, latency, and security. Two protocols dominate legacy and modern SCADA communication — Modbus and DNP3. Although both serve similar functions (data exchange between a control center and field devices), they differ significantly in architecture, layer structure, and functional philosophy. Modbus prioritizes simplicity and universality,… Read More »

Top 10 Free Modbus Troubleshooting Tools and Software

Here are top 10 free Modbus troubleshooting tools & software for troubleshooting and testing Modbus (RTU, TCP, ASCII) networks — all useful for diagnostics, simulation, or monitoring. I include a brief description of what each tool offers and why it’s worth considering. 1. OpenModScan Free/open-source Modbus Master (client) utility supporting both Modbus-TCP and Modbus-RTU. You can use it… Read More »

RS-485 vs Ethernet: Choosing the Right Network for Modbus

When setting up a Modbus network, one of the key decisions is choosing the right physical communication layer — RS-485 vs Ethernet. Both options support the Modbus protocol (Modbus RTU for RS-485 and Modbus TCP for Ethernet), but they differ in wiring, speed, distance, and application. This article explains the differences between RS-485 vs Ethernet for Modbus communication… Read More »

How We Can Convert Modbus RTU to Modbus TCP

In industrial automation, Modbus is one of the most common communication protocols used to connect devices such as sensors, controllers, meters, and SCADA systems.Over the years, two major versions of Modbus have been developed — Modbus RTU, which communicates over serial lines, and Modbus TCP, which communicates over Ethernet. As technology evolves, many industries face the challenge of… Read More »

Modbus RTU vs Modbus TCP/IP — Frame Structure and Key Differences

Modbus is one of the most widely used communication protocols in industrial automation and control systems. Originally designed for serial networks, Modbus evolved to work seamlessly over Ethernet and IP networks, creating two common variants — Modbus RTU and Modbus TCP/IP. Although both use the same core data model and function codes, they differ in frame structure, transmission… Read More »