SIEMENS Actuator SSA81U

Core Features "SSA81" Series & Functional Design: The "SSA81" denotes Siemens’ versatile medium-duty rotary actuator series, and the "U" (Universal) model emphasizes broad compatibility with dampers. It is a 24V AC-powered rotary actuator with a 90° rotation angle (standard for commercial dampers) and a torque rating of 9 Nm—ideal for mid-to-large air dampers in commercial HVAC systems (e.g., large VAV boxes, medium AHUs) or light industrial ductwork, where balanced torque, universal mounting, and reliable performance are prioritized. Dual Control Modes & Precision Feedback: Equipped with flexible control to adapt to diverse airflow needs: Modulating control (0–10V DC input): For variable air volume (VAV) systems or precision ventilation, enabling damper opening adjustment with ±1.5% positioning accuracy—critical for stable temperature control in office towers, hotels, or light industrial workshops. On/off control (24V AC input): For simple full-open/full-close scenarios (e.g., zone isolation dampers, AHU shutdown), ensuring rapid response to basic airflow demands. It includes built-in analog position feedback (0–10V DC) for real-time status monitoring, compatible with commercial building management systems (BMS) for centralized control and fault diagnosis. Robust & Space-Efficient Construction: Engineered with a corrosion-resistant aluminum alloy housing and a weight of 1.8 kg (3.97 lbs), suitable for wall, bracket, or direct damper mounting in commercial/light industrial spaces (e.g., HVAC mechanical rooms, factory duct enclosures). The housing features IP54 protection (dust-tight, water-resistant), withstanding commercial dust, moisture, and mild vibration—ideal for indoor climate-controlled environments. Safety & Reliability Features: Built with safeguards to ensure long-term uptime: Electronic overtorque protection: Automatically stops the motor if torque exceeds 9 Nm (e.g., jammed damper from debris or dust buildup), avoiding mechanical damage to the actuator or damper. Dual end-stop limits: Mechanical and electronic limits prevent over-rotation beyond 0° (closed) and 90° (open), protecting damper seals and extending component lifespan. Wide voltage tolerance: Accepts 24V AC (50/60 Hz) input with ±15% fluctuation tolerance, ensuring stability in standard HVAC control system power supplies. Universal Integration & Installation: Designed for seamless compatibility with Siemens BMS controllers (e.g., Desigo PX) and third-party PLCs via standard 0–10V analog signals. The "U" model includes a universal damper shaft adapter (fits 10–18 mm diameter shafts) and pre-labeled wiring terminals, reducing installation time by up to 25% vs. non-universal actuators. No specialized tools are required for setup. Typical Applications SIEMENS Actuator SSA81U is engineered for medium-duty rotary control of mid-to-large dampers—ideal for scenarios needing 9 Nm torque, universal compatibility, and commercial-grade durability in HVAC or light industrial ventilation. Key use cases include: Commercial Large VAV Boxes: Controlling dampers in large variable air volume (VAV) boxes for office towers, shopping malls, or hotels. Modulating control adjusts airflow to match multi-zone temperature demands, while IP54 protection withstands mechanical room dust—complying with EN 13141-6 (ventilation for non-residential buildings) and ASHRAE 90.1 (energy efficiency). Medium Air Handling Units (AHUs): Regulating supply/return air dampers in medium commercial AHUs (e.g., hospital wards, large retail stores). On/off control manages AHU startup/shutdown, and position feedback enables BMS monitoring of damper status—complying with EN 1886 (air handling units) and ISO 16813 (HVAC system design). Light Industrial Ventilation: Adjusting dampers in medium-sized factory ductwork (e.g., automotive component assembly, pharmaceutical packaging). Electronic overtorque protection handles occasional debris jams, and corrosion-resistant housing prevents damage from mild industrial dust—complying with ISO 12591 (industrial ventilation standards). Commercial Smoke Control Dampers: Controlling dampers in medium commercial building smoke management systems (e.g., hotel lobbies, small stadiums). On/off control enables emergency closure to contain smoke, and IP54 protection suits high-traffic public building mechanical spaces—complying with EN 12101-6 (smoke control dampers) and local fire codes