Real time VBNE and leakage current monitoring in hospital electrical systems: a low cost approach

Abstract Neutral to earth voltage (VBNE) in hospital electrical installations can reveal grounding issues or leakage currents that threaten patient safety and sensitive medical equipment. Patients with varying electrical resistances are particularly at risk, highlighting the need for continuous monitoring. This study presents a low cost, Arduino based relay system programmed in C + + for real time VBNE measurement, providing visual and audible alerts when thresholds are exceeded. The system compensates for rectifier losses and reliably distinguishes normal (≤ 1.5 V), warning (1.5–3 V), and fault (> 3 V) conditions, with an average response time below 150 ms. Validation on operational hospital circuits, benchmarked against a calibrated commercial leakage analyzer, showed consistent and reproducible results. This scalable system enhances electrical safety for patients, staff, and equipment, with potential improvements including isolated ADCs, remote logging, and automatic trip functions to strengthen monitoring in clinical settings.