Smart Manhole Guardian Intelligent Manhole Cover Monitoring Terminal

The First Sensor Intelligent Manhole Cover Monitoring Terminal (abnormal movement monitoring + ultrasonic liquid level monitoring) is an innovative product launched by First Sensor for smart city construction. With the rapid progress of urbanization, municipal, utility, power, and communication departments must manage a large number of manhole covers, which have become a critical part of urban operation. Traditional management methods suffer from insufficient monitoring, delayed information, and difficulty in detecting hidden dangers in time, which can easily pose threats to road safety and citizens’ travel. The intelligent monitoring terminal is designed to solve this long-standing problem in urban management.

The terminal is installed beneath the manhole cover and provides dual monitoring functions. On one hand, it can monitor abnormal movements of the cover in real time, and when tilting, opening, or disassembly occurs, the system immediately reports the abnormal status. On the other hand, the built-in ultrasonic liquid level sensor continuously monitors the well water level, predicting drainage network conditions and providing early warnings against flooding. All monitoring data are transmitted via NB-IoT and 2.4G wireless communication technologies to the municipal management platform. Personnel can check manhole cover and water level status anytime on a PC or mobile APP, achieving intelligent, visualized, and efficient management.

The terminal is also equipped with rich functional designs. It allows for basic information management such as numbering, GPS coordinates, and road attribution of manhole covers. In status monitoring, the device reports whether the cover is normal, abnormal, low power, opened, or removed. Once an alarm occurs, the system instantly locates and highlights the event, while simultaneously sending notifications to relevant personnel via mobile phone or email to ensure timely handling. The management platform supports work order dispatch, on-site maintenance, alarm clearance, and data archiving, forming a closed-loop process. Field inspectors can receive alarms, handle them on-site, and upload photos, thereby improving transparency and traceability. With electronic maps and text-based displays, the position, operational status, and historical data of manhole covers are clear at a glance, enabling authorities to maintain complete control.

In terms of performance, the terminal delivers excellent results. It operates at 3.6V supply voltage, with a detection accuracy of 1cm and a monitoring range of 0–2.5m. With an IP68 waterproof rating, it works reliably in environments from -20°C to +80°C. Transmission power is 7dBm ± 1dBm, powered by a large-capacity 8000mAh battery, ensuring 3–5 years of service life with static current consumption below 15μA. Robust hardware performance guarantees long-term stable operation in complex urban environments.

The value of the intelligent manhole monitoring terminal goes beyond cover monitoring—it is an essential component of smart urban management. Real-time monitoring of manhole covers helps prevent safety risks from displacement or theft. Monitoring of water levels enables early flood risk prediction before heavy rainfall, providing scientific evidence for flood prevention. By integrating weather information, the system dynamically adjusts warning strategies, ensuring faster and more efficient emergency response. Meanwhile, remote monitoring and intelligent scheduling significantly reduce manual inspection workloads, lowering operational and management costs.