SQM50.450R8H3 Siemens Damper Motor

Overview

The Siemens SQM50.450R8H3 is a high-precision reversing actuator designed for the accurate positioning of air dampers, fuel valves, and other components in industrial and commercial combustion systems. Engineered for durability and repeatable performance, this 24V motor is a critical component for load-dependent control in medium to large-scale burner applications. It features a robust design that allows for mounting in any position and is specifically configured for 0 to 135 Ohm input signals, making it ideal for systems requiring specific impedance-based control.

Features

• High-precision modulating accuracy and excellent rotational resolution
• Integrated auto/manual selector switch for easy adjustment and commissioning
• Manual forward/reverse toggle switch for direct control during setup
• Externally visible shaft position indicator for quick status monitoring
• Low hysteresis drive mechanism with double-offset drive and potentiometer gearing
• Disengagement clutches for the drive shaft and cam drum to allow manual positioning
• Support for up to six internal, easily adjustable SPDT switches (2 limit, 4 auxiliary)
• Field-reversible rotational direction (clockwise or counter-clockwise)

Specifications

• Model: SQM50.450R8H3
• Operating Voltage: 24 Vac (50/60 Hz)
• Torque: 140 in-lb (15 Nm)
• Running Time: 25 seconds for 90 degrees at 60 Hz (30 seconds at 50 Hz)
• Control Input: 0 to 135 Ohm
• Potentiometer: 135 Ohm, 90-degree range
• Rotation: Counter-clockwise (standard)
• Shaft: No shaft (ordered separately)
• Protection Rating: Designed for IP54 or NEMA 12 environments
• Approvals: UL recognized, CSA certified, and CE approved

Applications

• Precise positioning of air dampers in gas and oil burners
• Control of flow control valves and butterfly valves for fuel regulation
• Load-dependent combustion control in industrial boilers and furnaces
• HVAC and district heating system air and gas regulation
• Replacement of competitive actuators in existing burner management systems
• Use with Siemens LMV5 or similar high-demand burner control units