A Review on Smart Underground Cable Fault Detection with Location System

Underground power cables are widely used in residential, industrial, commercial, and utility distribution systems because they provide better safety, reliability, and protection from environmental conditions compared with overhead lines. However, when a fault occurs in an underground cable, detecting and locating the faulty portion is difficult because the cable is not directly visible. Conventional fault-location methods may require expensive instruments, skilled personnel, and considerable troubleshooting time. This paper presents a Smart Underground Cable Fault Detection and Sectional Location System Using ESP32 for low-cost monitoring and identification of faulty underground cable sections. The proposed system uses a voltage/continuity sensing arrangement, CD74HC4067 analog multiplexer, and ESP32 development board to sequentially monitor predefined cable sections. The ESP32 processes the sensed electrical condition and identifies the faulty section using experimentally determined threshold values. An LCD/OLED display provides the fault status, while LED and buzzer indicators provide local alerts. A relay can be incorporated for controlled isolation of the faulty circuit. The ESP32's Wi-Fi capability also provides a basis for future IoT-based remote monitoring. Mathematical relationships based on Ohm's law, cable resistance, voltage measurement, fault classification, detection accuracy, section identification accuracy, response time, and percentage error are used for system analysis. The proposed prototype focuses on sectional fault localization rather than claiming exact meter-level distance without calibration. The system can be further improved through resistance-per-unit-length calibration, IoT monitoring, mobile notification, GPS-based mapping, and advanced fault classification.