IoTOct 2025 — Presentin progress

Modbus TCP Machine Data Logger

IoT gateway that polls PLC registers over Modbus TCP and stores machine data for analysis.

Overview

A lightweight gateway service that reads production counters, temperatures and machine states from a PLC and writes them into a SQL database for dashboards.

Problem

Machine performance data stayed inside the PLC with no history, so downtime causes could not be analysed.

Solution

Implemented a Python polling service over Modbus TCP with configurable register maps, buffered writes to SQL and basic downtime classification.

Engineering process

Register mapping from the PLC program, polling interval tuning, schema design, resilience testing against network dropouts.

Results

Continuous machine history enabling downtime review and simple OEE-style reporting.

Control architecture

Control Loop Topology

Sensor

PLC

Control Logic

Actuator

Machine

Feedback loop