High voltage interrupting switch failure results in arc flash
June 30, 2019
Regulated industry sector: Electrical - High voltage electrical system (greater than 750V)
Injury description: NA
Injury rating: NA
Incident rating: Major
During a routine isolation process to install equipment and record measurements to facilitate future retrofit installations of breakers, a main high voltage interrupting switch for a transformer failed when opening, resulting in an arc flash and damage to the equipment.