Scalable and reliable temperature monitoring system based on Raspberry Pi and OPC UA for Detector Control and Safety Systems

Abstract

This study presents optimizations to the Massive Temperature Readout System (MTRS), a cost-effective alternative to traditional Programmable Logic Controller(PLC)-based systems for large-scale temperature monitoring. The improved MTRS design streamlines hardware by eliminating intermediate microcontrollers and communication modules, reducing complexity and potential failure points. A unified multi-threaded C++ application replaces the original multi-process software, enhancing performance and managing sensor data acquisition and Open Platform Communications Unified Architecture(OPC UA) server functions within a single process. Furthermore, a novel sensor reading strategy is implemented, overlapping conversion times to achieve higher system performance and increased channel capacity. The optimized system demonstrates the feasibility of a cost-effective, high-performance temperature monitoring solution for integration with OPC UA based industrial communication infrastructures.