AITOLY MFM Series Thermal Mass Flow Meter

Overview

The AITOLY MFM Series Thermal Mass Flow Meter is an industrial-grade, direct mass flow measurement instrument engineered for high-reliability gas flow monitoring in demanding process environments. Utilizing constant-temperature anemometry (CTA) principle, the device measures gas mass flow by detecting heat transfer between a heated sensor element and the flowing gas stream—eliminating dependence on gas density, temperature, or pressure variations. Unlike volumetric flowmeters, the MFM Series delivers true mass flow output (standard cubic centimeters per minute — SCCM — or standard liters per minute — SLPM) without external compensation, making it ideal for applications requiring stoichiometric control, gas blending, or trace-level delivery where repeatability and zero stability are critical. Its solid-state architecture—featuring no moving parts—ensures long-term operational integrity under continuous duty cycles typical in semiconductor fabrication, analytical instrumentation, and clean-energy systems.

Key Features

• No moving parts: Eliminates mechanical wear, drift, and maintenance downtime—engineered for >50,000 hours of continuous operation.
• Integrated thermal and pressure sensing: Onboard temperature and absolute pressure transducers enable real-time compensation for gas composition and ambient condition fluctuations.
• Dual-parameter digital display: Simultaneous readout of instantaneous mass flow rate and cumulative flow volume on a backlit monochrome LCD with tactile membrane keypad navigation.
• Multi-protocol communication: Native support for RS232, RS485 (Modbus RTU), CAN bus, plus analog outputs (0–5 VDC and 4–20 mA) for seamless integration into PLC, DCS, and SCADA platforms.
• Wide dynamic range: Linear measurement capability from 0.5% to 100% of full scale ensures accurate low-flow detection and high-flow handling within a single instrument.
• Robust wetted materials: Flow body constructed from electropolished SUS304 or optional high-purity SUS316L stainless steel; FKM seals compatible with aggressive gases including O₂, N₂, Ar, He, H₂, CO₂, NH₃, and process-compatible mixtures.
• Rapid response: <1 second time constant enables closed-loop feedback control in fast-transient processes such as plasma etch gas pulsing or laser-assisted welding purge regulation.

Sample Compatibility & Compliance

The MFM Series is validated for use with non-corrosive and mildly corrosive gases across vacuum to medium-pressure regimes (up to 3 MPa). It complies with IEC 61000-6-2 (EMC immunity) and IEC 61000-6-4 (EMC emissions) standards. While not intrinsically safe certified, its low-power design (<1.2 W) and isolation-rated analog outputs permit deployment in Class 1 Div 2 environments when installed per NEC Article 500 guidelines. For regulated industries—including pharmaceutical process gas monitoring and semiconductor tool OEM integration—the meter supports audit-ready data logging when paired with compliant host software, aligning with ALCOA+ principles for data integrity. Though not FDA 21 CFR Part 11–certified out-of-the-box, its deterministic analog/digital outputs and timestamp-capable firmware facilitate validation under GMP/GLP frameworks.

Software & Data Management

Configuration and calibration are performed via ASCII command protocol over RS232 or Modbus RTU over RS485. AITOLY provides a Windows-based PC utility (MFM ConfigTool) supporting zero/span adjustment, gas selection (preloaded library of 20+ gases), unit conversion, and firmware updates. Raw flow data can be streamed at up to 10 Hz for real-time analysis in MATLAB, LabVIEW, or Python-based acquisition systems. The 4–20 mA output is linearly scaled to full-scale flow range and retains NIST-traceable linearity per calibration certificate (included). Optional USB-to-serial adapters enable direct laptop connectivity without additional drivers.

Applications

• Semiconductor manufacturing: Precise gas delivery control in RIE and DRIE etch tools, CVD/PVD chamber purging, and leak-check calibration.
• Analytical instrumentation: Carrier and make-up gas flow regulation in GC, GC-MS, and FTIR systems—meeting ASTM D6345 and ISO 8573-1 purity class requirements.
• Hydrogen energy infrastructure: Fuel cell stack inlet flow monitoring, electrolyzer feed control, and hydrogen blending verification in natural gas pipelines.
• Medical device manufacturing: Sterile gas flow verification during packaging, plasma sterilization, and laser welding of implantable components.
• Research laboratories: Low-flow gas mixing for catalysis studies, environmental simulation chambers, and MEMS fabrication process development.

FAQ

Does the MFM Series require periodic recalibration?
Yes—AITOLY recommends annual calibration against a NIST-traceable primary standard for applications governed by ISO/IEC 17025 or internal quality protocols. Factory calibration includes zero and span verification at two points across the selected flow range.
Can the meter measure mixed gases?
It supports user-defined gas mixtures via weighted average thermal conductivity input; however, accuracy degrades beyond ±2% FS if composition varies dynamically without inline gas analysis feedback.
Is firmware upgrade supported in-field?
Yes—via RS232 using the MFM ConfigTool; firmware version, serial number, and calibration date are queryable via ASCII command set.
What is the minimum measurable flow for the 500 SCCM model?
The lower limit is 2.5 SCCM (0.5% of 500 SCCM FS), with guaranteed accuracy down to 5 SCCM per ISO 14644-3 Annex B guidance for laminar flow stability.
Are explosion-proof variants available?
Not as standard; however, AITOLY offers custom ATEX/IECEx-certified housings and barrier-isolated analog outputs upon request for Zone 1/21 deployment.