LF24-3 US Belimo Actuator

Datasheet

Installation Guide

Application

For modulation or On/Off, fail-safe control of dampers in HVAC systems. Actuator sizing should be done in accordance with the damper manufacturer’s specifications. The actuator is mounted directly to a damper shaft from 3/8” up to 1/2” in diameter by means of its universal clamp, 1/2” shaft centered at delivery. For shafts up to 3/4” use K6-1 accessory. A crank arm and several mounting brackets are available for applications where the actuator cannot be direct coupled to the damper shaft. Control is floating point from a triac or relay, or On/Off from an auxiliary contact from a fan motor contactor, controller or manual switch.

Operation

The LF series actuators provide true spring return operation for reliable fail-safe application and positive close-off on air tight dampers. The spring return system provides consistent torque to the damper with, and without, power applied to the actuator. The LF series provides 95° of rotation and is provided with a graduated position indicator showing 0 to 95°. The LF uses a brushless DC motor which is controlled by an Application Specific Integrated Circuit (ASIC) and a microprocessor. The microprocessor provides the intelligence to the ASIC to provide a constant rotation rate and to know the actuator’s exact fail-safe position. The ASIC monitors and controls the brushless DC motor’s rotation and provides a digital rotation sensing function to prevent damage to the actuator in a stall condition. The actuator may be stalled anywhere in its normal rotation without the need of mechanical end switches. Power consumption is reduced in holding mode.

Specifications

• Angle of Rotation
  • 95°
• Direction of Rotation (Fail-Safe)
  • Reversible with cw/ccw mounting
• Power Consumption (Holding)
  • 1 W
• Safety Function
  • YES
• Shaft Diameter
  • 3/8…1/2″ round
  • centers on 1/2″
• Actuator Type
  • Spring return
• Application
  • Air
• Control Type
  • Floating/3-point
• Degree of Protection
  • IP54
  • NEMA 2
• Electrical Connection
  • Cable
• Power Consumption (Running)
  • 5 W
• Product Type
  • Actuator
• Protection category
  • IP54
• Running Time (Fail-safe)
  • <25 s
• Running Time (Motor)
  • 150 s constant
  • independent of load
• Torque
  • 35 in-lb [4 Nm]
• Voltage AC/DC
  • AC/DC 24 V