An IoT Sensor Platform for Predictive Maintenance of High Voltage Circuit Breakers

This paper presents the design, implementation, and validation of an IoT-based sensor platform for predictive maintenance of high-voltage circuit breakers (HVCBs), essential components in power transmission systems. Mechanical failures account for more than half of major HVCB failures, emphasizing the need for reliable, long-term condition monitoring. The proposed platform is specifically developed for real-world deployment and enables non-intrusive, synchronized measurement of vibration and coil current signals during switching events, sampled at 100 ksps and 10 ksps, respectively. Triggering of the measurement is achieved via hardware detection of coil current with a response time below 115 µs. Data is recorded directly to a microSD card, with optional USB streaming for testing and Wi-Fi transfer to a gateway connected to cloud storage. The system supports virtually unlimited recording duration and rearms for subsequent events in under one second, facilitating continuous operation. The platform was validated through extensive laboratory testing and real-world deployment at a Swiss Federal Railways (SBB) substation with a HVCB operating at 132 kV. Among the two, more than 500 circuit breaker operations were recorded without failure, demonstrating long-term reliability and robustness in high-voltage environments. By enabling long-term monitoring in operational substations, it addresses a critical gap in both research and industrial practice, and contributes a practical solution for improving grid reliability and reducing maintenance costs.