MS Two-Position Actuator

MS Two-Position Actuators are designed for use in Smoke Control Systems. If power fails, the actuator spring returns to the 0° position. The actuator mounts flush with the damper box. The actuator drives from 0° to 95° and spring returns back to 0°. The actuators are operated by an spst two-position controller. When using an spst two-position controller, the actuator drives to the damper fully open position when controller contact makes and spring returns to the damper fully closed position when controller contact breaks. The actuator drops to holding power level on detection of stall, independent of hub position. actuator accepts an on/off signal from a single-pole, single-throw (spst) controller. Reversible mounting allows actuator to be used for either clockwise (cw) or counterclockwise (ccw) spring rotation. Designed to operate reliably in smoke control systems requiring Underwriter’s Laboratories Inc. UL555S ratings up to 350°F, if applicable

• 175 lb-in. (20 Nm) minimum driving torque at 350°F (176°C).
• Reversible mounting facilitates use in either clockwise (cw) or counterclockwise (ccw) spring
• rotation.
• Integral spring return ensures level of return torque.
• Fifteen-second spring return timing.
• No special cycling required during long-term
• holding. (See Operation section.)
• No audible noise during holding.
• Models available for 24, 120, and 230 Vac applications.
• Ninety-five degree angle of rotation.
• Actuator holds rated torque at reduced power level.
• Die-cast aluminum housing.
• Housing design allows flush mounting to damper.

• US 6,505,991
• UL555S