ActronAir Soft Starter Start Capacitor 200-260uF 330V 46x86mm Slot Mount is the start capacitor for ActronAir soft starter assemblies, providing the high-capacitance boost current required during motor starting before switching out of circuit once the motor reaches running speed. Start capacitors carry much higher capacitance values than run capacitors but are rated for intermittent duty only -- a start capacitor left in circuit continuously will overheat and fail. Isolate power at mains before replacing any capacitor components.