Belimo NMCB24-SR Motor Actuator

The Belimo NMCB24-SR is a high-torque rotary actuator designed for precise control in HVAC applications requiring 90 in-lb torque. Operating on a 24VAC/DC power supply, this unit utilizes a 2-10 VDC modulating control signal to provide proportional positioning for dampers and valve assemblies. Built with a brushless DC motor, the NMCB24-SR ensures consistent electronic stall protection across its full 95-degree rotation, eliminating the need for mechanical limit switches. This actuator is engineered for long-term reliability in demanding environments, offering a 95-second run time and a manual override button for field commissioning. The universal clamp facilitates direct mounting on shafts ranging from 5/16" to 3/4", making it a versatile drop-in replacement for failed non-spring return actuators. Its NEMA 2 (IP54) rated enclosure ensures protection against dust and moisture in mechanical rooms, providing technical precision for complex building automation systems.

• Precise Modulating Control: The 2-10 VDC feedback signal provides accurate position sensing for integrated building controllers.
• High Torque Output: Delivers 90 in-lb of torque, sufficient for medium-sized air dampers and specialized valve retrofits.
• Flexible Compatibility: Accepts both 24V AC and DC input, simplifying field wiring and stock requirements.
• Extended Service Life: Microprocessor-controlled DC motor prevents burnout under stalled conditions without overheating.
• Simplified Installation: Features a manual override button and a universal mounting bracket to reduce time on the job site.

Can I use a 4-20mA signal with the NMCB24-SR?
Yes, by installing a 500? resistor across the input leads, you can convert a 4-20mA signal to the required 2-10 VDC modulating range.

What happens if the actuator stalls mid-stroke?
The internal overload protection senses the stall and halts power to the motor, preventing damage to the gear train until the obstruction is cleared.

Is this a spring-return unit for fail-safe applications?
No, the NMCB24-SR is a non-spring return actuator. It will maintain its last position upon loss of power unless integrated into a fail-safe circuit with an external power source.

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.