Belimo GKB24-SR

Damper Actuator, 360 in-lb [40 Nm], Electronic fail-safe, AC/DC 24 V, 2...10 V, modulating

For proportional modulation of dampers in HVAC systems. The GKB24-SR and GKX24-SR provide electrical power off operation for reliable fail-safe application.

The actuator is mounted directly to a damper shaft up to 1.05” in diameter by a universal clamp. A crank arm and several mounting brackets are available for applications where 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 20mA control input from an electronic controller or positioner. A 2 to 10 VDC feedback signal is provided for position indication or master-slave applications.

The GKB24-SR provide 95° of rotation and a visual indicator shows the position of the actuator. When reaching the damper or actuator end position the actuator automatically stops. The gear can be manually disengaged by pressing the button located on the actuator cover.

The GKB24-SR actuators use a brushless DC motor, which is controlled by an Application Specific Integrated Circuit (ASIC). The ASIC monitors and controls the actuators rotation and provides a digital rotation sensing (DRS) function to prevent damage to the actuator in a stall condition. Power consumption is reduced in a holding mode.