Siemens SAS61.33U 24V Spring Return Electronic Valve Actuator with 0-10 VDC Proportional Control

The Siemens SAS61.33U is a spring return electromechanical valve actuator from the Powermite 599 MT Series, designed for proportional control of HVAC terminal unit valves. This actuator operates on 24 VAC or 24 VDC power supply and accepts 0-10 VDC or 4-20 mA control signals to provide precise valve positioning in building automation systems.

Key Features:

• Spring return fail-safe operation with automatic return in less than 14 seconds upon power loss
• 30-second positioning time for responsive control
• 400 N (90 lbs) positioning force for reliable valve actuation
• Compatible with Powermite 599 MT Series terminal unit valves with 7/32 inch (5.5mm) stroke
• Low power consumption: 5.9 VA running, 4.8 VA holding
• NEMA 1 rated enclosure for indoor applications
• Operating temperature range: 41°F to 122°F (5°C to 50°C)
• Operates in up to 95% relative humidity, non-condensing

This actuator replaces the legacy SQS65.5U model and provides backward compatibility with existing Siemens valve systems. The proportional control capability allows for precise modulation of heating and cooling valves in VAV systems, fan coils, and other HVAC applications requiring accurate temperature control.