Belimo NKQB24-SR Actuator

The Belimo NKQB24-SR is a high-speed, electronic fail-safe actuator engineered for precise control in HVAC systems requiring rapid response times. Operating on a 24Vac/dc power supply, this unit delivers 54 in-lb of torque and features a programmable 2-10Vdc proportional control signal. Designed for demanding applications, the NKQB24-SR provides a critical 4-second run time and a dedicated fail-safe position via integrated capacitors, ensuring dampers or valves return to a predetermined safety state during power loss. This linear or rotary actuator is compatible with a wide range of standard control valve linkages and damper shafts, making it a reliable choice for smoke control, laboratory ventilation, and critical process environments. The brushless DC motor technology eliminates the risk of burnout while providing consistent modulating control, even in high-cycle installations. Proper field calibration of the operating range and feedback signals ensures seamless integration with building automation systems.

Key Benefits

• High-speed 4-second operation ensures immediate response for pressure-critical or safety-related sequences.
• Electronic fail-safe technology utilizes reliable capacitors to move the actuator to the home position without mechanical springs.
• Universal 24V power input and standard 2-10Vdc control signal allow for easy retrofitting across various BAS platforms.
• NEMA 2 (IP54) enclosure provides protection against dust and moisture in typical mechanical room environments.
• Brushless DC motor technology delivers maintenance-free longevity and improved stalling protection over traditional motors.

Common Questions

What is the difference between the NKQB24-SR and standard spring-return actuators?
The NKQB24-SR uses electronic capacitors for the fail-safe function rather than a mechanical spring, allowing for a more compact design and faster 4-second running time compared to standard models.

Can the fail-safe direction be changed in the field?
Yes, the direction of the fail-safe position (Normally Open or Normally Closed) can be selected via a switch on the actuator housing to match specific application requirements.

Does this actuator support manual override?
This model includes a manual override crank or button that allows technicians to position the actuator during commissioning or emergency maintenance when power is disconnected.

This item is not eligible for free shipping.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.