Trolley-pole retrieval method and apparatus

摘要

A trolley pole retrieval method and apparatus. A sensing circuit senses threshold values of voltage and continuity in the vehicle power supply circuit, the vehicle motion and the distance travelled. The system responds to the sustained simultaneous conditions of low voltage and open circuit in the power supply circuit while the vehicle is in motion by enabling a distance counter. If the vehicle remains in motion under conditions of low voltage and low continuity for a predetermined distance, trolley pole dewirement is assumed and a retrieval pulley is actuated to return the trolley pole to the vehicle. This prevents damage to overhead power lines.