Abstract: A power line worker was changing the taps on a transformer to reduce the voltage to a customer's residence. The employee had climbed a utility pole that he was not able to access with his aerial lift. He opened one cutout and removed the corresponding high-voltage-side connection on the transformer. He swung to the other side of the pole and removed the other high-voltage-side jumper without opening its cutout. As the employee opened the lid of the transformer, it apparently contacted the energized primary conductor, causing an electrical fault. The ensuing electric arc and electric shock knocked the employee unconscious momentarily. After regaining consciousness, he was able to climb down the pole and walk to his truck to call for help. He was hospitalized with burns to his right hand.