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.
74 articles
Time synchronization for industrial data: NTP, PTP and timestamp discipline
Why timestamps decide whether data can be trusted, where NTP is enough, when PTP is worth the effort, and how to choose a single time source and timestamp convention.
The 12 readiness questions explained: what evidence to collect
Each question in the IT/OT readiness worksheet explained: why it matters, what “verified” looks like and which evidence to bring to the kickoff meeting.
MQTT topic design for factories: a unified namespace you can maintain
How to structure MQTT topics with an ISA-95-style hierarchy, what belongs in the topic versus the payload, how retained messages and last will fit, and which anti-patterns to avoid.
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.
Process unit conversion pitfalls: gauge vs absolute, normal vs standard volume
The conversions that cause real mistakes in process data: gauge versus absolute pressure, temperature offsets, volumetric versus mass flow, and normal versus standard cubic meters.
Reading a sensor CSV: outliers, drift and flatlines before analytics
A short routine for checking an exported sensor file: timestamps, missing samples, z-scores and outliers, drift and frozen values, and what to do before data reaches a dashboard or a model.
Sizing an IIoT data budget: sampling, deadband and retention
How tag count, sampling interval, payload size, overhead and retention combine into bandwidth and storage numbers, and how deadband and compression change them.
IPv4 subnet planning for OT networks: CIDR, VLANs and address plans
A practical method for sizing OT subnets: how CIDR maps to host counts, how to leave room to grow, how to align subnets with cells and zones and how to document the plan.
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.
MTBF and MTTR: how to calculate them and where they mislead
Definitions, formulas and a worked example for MTBF and MTTR, plus the pitfalls: what counts as a failure, what counts as repair time and why averages hide long outages.
OEE worked example: from shift data to a loss waterfall
Follow one 8-hour shift through the OEE formula: availability, performance, quality and a minute-by-minute loss waterfall you can reproduce in the free calculator.
A low-disruption connectivity pilot for legacy machines
Prove the smallest useful read-only data path before changing a production network or replacing equipment.
Design an energy-monitoring pilot around one question
Choose a useful meter boundary, separate demand from consumption and connect the result to a production decision.
Size historian retention with a measured data budget
Estimate the data path, separate sampling from storage and validate compression before choosing capacity.
Write a data contract your automation and IT teams can both use
Define meaning, timing, quality and ownership so an industrial tag remains understandable outside its source system.
The first 30 days of an IT/OT project
A working plan for manufacturing teams: define one outcome, prove one data path and make the pilot acceptance measurable.
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.
An OEE pilot is only as good as its counters
Commission an OEE data path by agreeing on time boundaries, ideal cycle time and the meaning of a good part.
Topic hubs
Each hub lists the articles on one subject in a suggested reading order.
Planning an IT/OT project?
Describe your machine, data flow or production goal in a few sentences and the ASP Dijital team will reply by email.