Design and Evaluation of a Password-Based Switching Authorization System for Electric Lineman Safety

Maintenance on de-energized distribution lines is endangered by unintended re-energization, a hazard that conventional verbal switching coordination cannot exclude. This paper presents the design of a password-based switching authorization system in which an Arduino-based controller accepts a password from a matrix keypad, validates it, and, only on a valid entry, signals a relay interface that switches a low-voltage demonstration load; an LCD and a buzzer provide status and alerts. We specify the architecture, a state model of the controller, a proposed authentication and switching algorithm, and a reproducible test protocol with acceptance criteria. A safety analysis identifies password compromise, tampering, relay and controller faults, and power loss as the dominant residual risks, and argues that automatic relay closing after maintenance is hazardous and should be replaced by deliberate authorization combined with independent confirmation that work is complete. No experimental measurements are yet available, so no performance claims are made. The system is positioned as an additional authorization measure, not a substitute for electrical isolation, lockout/tagout and verification of de-energization.