... control on modulating valve. 1. SERVICE ENVIRONMENT1.1 Power supply: Single phase, 220 V, AC, 50 Hz (or 110 V, 50 Hz ... : 0.6% ~ 5% adjustable1.6 Duty: S5 ( Intermittent operation with electric braking), Minimum duty factor 25%,Maximum operations 1200 times/hour1 ... and closing, protection for over torque, and travel limit, etc. ELECTRIC LINEAR TRAVEL MODULATING VALVE ACTUATORS