Siemens-SQN75.494A21-Stellantrieb

Siemens SQN75.494A21 actuator: compact drive for precise air damper control. Buying Siemens SQN75.494A21 means equipping your burner installation with a reliable electric drive for precise air supply regulation. This model is specially designed for small and medium power gas and liquid fuel burners and ensures optimal fuel-air mixture ratio for maximum efficiency and equipment safety. Purpose and application: The Siemens SQN75.494A21 actuator is intended for rotating air dampers of burner devices, controlling the exact ratio of burned fuel and air mixture. It is integrated into single-stage, two-stage, or modulating burners of small and medium power. Main functions of the actuator: Positioning the damper during ignition — supplying the amount of air necessary for safe ignition; Controlling the damper during low-fire and high-fire operation; Opening the damper during combustion chamber purging to remove residual gases. The actuator is controlled by flame management systems (burner managers) that are part of the control automation and determine the required air-to-gas (or liquid fuel) proportion. Technical specifications of Siemens SQN75.494A21: The SQN75.494A21 actuator is equipped with a reversible electric motor. Below are the full technical specifications of the device: Electrical parameters: Supply voltage: 220 V (tolerance -15%…+10%); Supply frequency: 50…60 Hz ±6%; Power consumption: 6 VA (20 W according to other data); Motor type: reversible synchronous with anti-locking protection. Mechanical characteristics: Torque (nominal): 2.5 Nm; Torque (holding): 1.2 Nm; Rotation time for 90°: 12 seconds; Rotation direction