Schneider Electric (Barber Colman) 21-153 Restrictor

The Schneider Electric (Barber Colman) 21-153 In-Line Restrictor is a critical pneumatic component engineered for precise airflow regulation in HVAC control systems. Specifically designed for use with NCS-TUBE or standard 1/4" poly tube, this 0.007 orifice restrictor provides a calibrated flow rate of 1.0 SCFH (28.32 L/H) at a 20 psig reference. This component is essential for maintaining signal stability in transmitters and bleed-type units, preventing overpressure damage to sensitive downstream sensors and actuators. As a direct functional equivalent to the N100-2501, it offers a seamless drop-in solution for legacy pneumatic maintenance and repairs. The red-coded housing allows for immediate visual identification of its flow characteristics during field service. Built for high-reliability industrial environments, the 21-153 restrictor ensures consistent impedance in your air lines, safeguarding the integrity of the entire pneumatic circuit against pressure fluctuations that could compromise control accuracy.

Key Benefits:

• Precision Calibration: Delivers a consistent 1.0 SCFH flow rate to ensure accurate pneumatic signals in complex HVACR control loops.
• Broad Compatibility: Fully interchangeable with the N100-2501 and optimized for standard 1/4" poly tubing installations.
• System Protection: Acts as a reliable 0.007 orifice barrier to protect low-pressure transmitters from sudden air surges.
• Professional Identification: Red color-coding facilitates fast identification during system audits and multi-zone troubleshooting.
• Durable Construction: Engineered to withstand the demands of industrial compressed air systems without performance degradation.

Common Questions:

What is the primary function of the 21-153 in a pneumatic circuit?
It serves as a fixed restriction to control the rate of air bleed or to establish a specific pressure drop, which is vital for the proper operation of bleed-type pneumatic sensors and transmitters.

Is this part interchangeable with non-Schneider systems?
Yes, the 21-153 is technically identical to the N100-2501 and can be used in any system requiring a 1.0 SCFH restrictor with 1/4" tubing connections.

Does the orientation of the in-line restrictor matter?
While pneumatic flow is generally bi-directional through the orifice, it is best practice for contractors to follow the signal flow direction consistent with the existing system architecture for ease of future maintenance.

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.