For proportional modulation of dampers in HVAC systems. Actuator sizing should be
done in accordance with the damper manufacturerâ€™s specifications.
The actuator is mounted directly to a damper shaft up to 1.05" in diameter by means
of its universal clamp. A crank arm and several mounting brackets are available for
applications where the actuator cannot be direct coupled to the damper shaft.
The actuator operates in response to a 2 to 10 VDC, or with the addition of a 500 ohm
resistor, a 4 to 20 mA control input from an electronic controller or positioner. A 2 to
10 VDC feedback signal is provided for position indication. Not to be used for a
The EFB24-SR 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 actuatorâ€™s exact fail-safe position. The ASIC monitors and controls
the brushless DC motorâ€™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.