Abstract: The electrical power supply cables (shunt cables) of a robotic welding machine are continuously monitored during welding operations to determine cable fatigue resulting from mechanical flexing and high electrical current flow. Increases in cable resistance, being representative of a fatigued cable, are determined by measuring voltage across the cables. When a threshold voltage level or threshold voltage increase is reached, a monitor outputs a signal alerting plant personnel of the fatigued cable. The alert signal may further provide plant personnel with a predetermined time to cold weld failure of the fatigued cable, allowing plant personnel to schedule replacement of the fatigued cable during production breaks or scheduled downtime. In one embodiment, robotic welders and associated cable monitors are networked to a centralized computer to identify and isolate fatigued cables.