VFC for PM2.5 Hi-Vol Air Sampler, 110V Brushless Systems with Orifice & Lookup Table SKU: TE-10557PM2.5BL

The TE-10557PM2.5BL Volumetric Flow Controller (VFC) provides precise flow control for PM2.5 high volume ambient air samplers equipped with brushless motor systems. This controller uses a critical orifice with a predetermined orifice hole diameter to control the flow rate, drilled and calibrated to let only the predetermined flow rate to pass through the filter while the motor operates wide open to maintain a constant flow rate.

How VFC Technology Works

The VFC controller is a critical orifice with a predetermined hole diameter. The critical orifice is calibrated in a NIST traceable lab to determine the volumetric flow rate. The motor runs wide open and as air passes through the critical orifice, the sampler runs at a predetermined flow rate. This proven technology ensures consistent sampling performance throughout the monitoring period, critical for EPA-compliant ambient air quality measurements.

Key Specifications

• Voltage: 110V/60Hz
• Compatible with brushless motor systems only
• Includes calibrated VFC orifice and lookup table
• Designed for PM2.5 collection (particles with aerodynamic diameter of 2.5µm or less)

System Compatibility

This VFC is specifically engineered for PM2.5 high volume air samplers with brushless motor assemblies operating at 110V. Brushless style motors do not use motor brushes or require maintenance, are higher in cost and do not have any emissions. The TE-10557PM2.5BL is not compatible with brush-style motor systems — for brush-style systems, use the standard TE-10557PM2.5.

Important: Ensure your sampler uses a brushless motor assembly before ordering. Using the wrong VFC type can result in improper flow rates and non-compliant sampling data.

Installation and Calibration

Each VFC includes a pre-calibrated orifice and corresponding lookup table specific to the orifice's flow characteristics. The lookup table provides the relationship between differential pressure measurements and actual volumetric flow rates, ensuring accurate flow determination under varying atmospheric conditions. Installation should follow Tisch Environmental's recommended procedures for VFC replacement in brushless sampler systems.

Regulatory Compliance

This VFC supports EPA-compliant PM2.5 ambient air monitoring as specified in 40 CFR Part 50, Appendix L. EPA reference methods require a sample flow rate of 16.67 liters/min for 24-hour average measurements of PM2.5, and this VFC ensures consistent flow control to meet these regulatory requirements for NAAQS compliance monitoring.