Belimo ZG-NMSA-1 Shaft Extension

The Belimo ZG-NMSA-1 Shaft Extension is a critical accessory for HVAC contractors performing damper actuator retrofits or new installations where existing drive shafts are too short to reach the actuator clamp. Engineered specifically for 1/2 inch diameter shafts, this extension provides an additional 3.8 inches of length (with a 2-inch effective extension in some configurations), ensuring a secure mechanical connection between the damper and Belimo NM series actuators. Built from high-grade cylindrical metal, it features a hollow bore design and integrated set screws to maintain high torque transfer without slippage. By utilizing the ZG-NMSA-1, technicians can avoid expensive damper replacements when the original shaft length is insufficient, allowing for seamless integration of direct-coupled actuators in tight plenum spaces or deep duct applications. Its robust construction ensures concentric rotation and eliminates the risk of binding common in improvised linkage setups.

• Optimized Compatibility: Designed for a precision fit on standard 1/2" diameter shafts, ensuring no mechanical play during operation.
• Extended Reach: Provides the necessary clearance for Belimo NM actuators when mounting on recessed dampers or through thick insulation.
• High Torque Transfer: Includes dual set screws for a rigid, slip-resistant grip on the primary shaft, maintaining actuator performance and positioning accuracy.
• Durable Construction: Heavy-duty metal sleeve designed to withstand the operational stressors of commercial HVAC air distribution systems.
• Simplified Retrofitting: Eliminates the need for complex crank arm kits or custom fabrications, reducing labor time on the job site.

Common Questions

Which Belimo actuators are compatible with the ZG-NMSA-1?
This shaft extension is primarily designed for use with the NM series actuators but can be utilized in various applications requiring a 1/2" diameter extension. Always verify that the total torque requirements do not exceed the mechanical limits of the extension sleeve.

How do I ensure the extension does not slip on the damper shaft?
The ZG-NMSA-1 utilizes high-tensile set screws. To ensure a professional-grade fit, ensure the damper shaft is clean and free of debris before sliding the extension on, then tighten the set screws to the manufacturer-specified torque to prevent rotational play.

Can this be used for shafts larger or smaller than 1/2 inch?
No, this specific model is bored precisely for 1/2" shafts. For 3/4" shafts or other sizes, a different shaft adaptor or extension kit, such as the AV series, must be selected to maintain the integrity of the HVAC drive assembly.

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.