Technical articles for industrial IT and OT teams
74 articles on OEE, Modbus, OPC UA and MQTT, OT security, industrial data, edge computing and IT/OT project planning.
11 articles · connectivity
OPC UA security basics: modes, policies and certificate trust
What Sign and SignAndEncrypt actually change, which security policies to avoid, how application certificates and trust lists work, and the connection errors you will meet first.
32-bit floats in Modbus: ABCD, CDAB, BADC and DCBA byte orders
Why a perfectly valid register pair turns into nonsense, how IEEE 754 single precision is split across two registers and how to find the right byte and word order.
Modbus addressing and function codes: why 40001 is register 0
A reference-style guide to Modbus data tables, 0-based versus 1-based addresses, the common function codes and exception responses, with the classic off-by-one trap explained.
A low-disruption connectivity pilot for legacy machines
Prove the smallest useful read-only data path before changing a production network or replacing equipment.
Validate a Modbus register map before commissioning
A practical sequence for checking offsets, signedness, byte order and scaling before register values reach a dashboard.
Test MQTT recovery before the first network outage
A factory data test plan for disconnects, stale values, duplicate messages and replay behavior.
A PLC backup is not complete until recovery is tested
Plan a restore drill that checks project files, licenses, hardware dependencies and operational acceptance.
MQTT QoS Levels Explained for Industrial Messaging
QoS 0, 1, and 2 are often misread as reliability tiers. What they actually guarantee - and how to choose per message class.
Wireless Sensor Networks in Harsh Industrial Environments
Heat, metal, vibration, and interference make factory wireless hard. How to design wireless sensor networks that survive real plants.
IIoT Connectivity Options: Cellular, Wi-Fi, LoRaWAN, and Wired
There is no best wireless technology - only the right one for the distance, data rate, and power budget. A selection guide.
OPC UA vs MQTT: When to Use Each in an Industrial Architecture
OPC UA and MQTT solve different problems. This guide maps each protocol to the architecture where it earns its place.
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