Nexisense MF-4000 Series Gas Mass Flow Meter | MEMS Micro Gas Flow Meter 3mm/8mm Diameter RS485 RS232 Analog Output Precision Thermal Mass Flow Sensor

Focus Section

Solving the pain points of precision metering for low-velocity gas flow in micro-diameter pipes, providing MEMS direct measurement, high sensitivity, and uncompensated mass flow solutions.

Nexisense MF-4000 series micro gas mass flow meters (MF-4003/MF-4008) are specially designed for 3mm and 8mm diameters. Maximum flow options include 2.3~5 SLPM (MF-4003) and 10~50 SLPM (MF-4008), with an accuracy of ±(1.5+0.2FS)% and repeatability of 0.25%. The pressure loss is as low as 100Pa, making it particularly suitable for high-precision metering of common gases such as Air, Nitrogen, Oxygen, Argon, and Carbon Dioxide.

Three Core Selling Points:

• MEMS High-Precision Micro-Flow Measurement: Based on the thermal mass principle, multiple sensors are integrated on a single chip, with a turndown ratio of 100:1. It features high sensitivity, allowing accurate metering even for extremely small initial flows, without the need for temperature and pressure compensation, and excellent repeatability (0.25%).

• Low Pressure Loss & Fast Response: The maximum pressure loss is only 100Pa (MF-4003) ~ 600Pa (MF-4008). The response time is 10ms (adjustable from 20 to 1000ms), minimizing the impact on the pipeline system, suitable for precision process control.

• Multi-output & Easy IoT Integration: Supports linear analog voltage 0.5-4.5VDC, RS232/RS485 (Modbus optional), and 4-digit 7-segment LED digital tube display (Instantaneous SLPM + Cumulative SL). Three buttons make operation convenient for connecting to PLC, DCS, or host computer systems to achieve real-time data acquisition and remote monitoring.

Overview

Nexisense MF-4000 series gas mass flow meters (models MF-4003 with 3mm diameter, MF-4008 with 8mm diameter) are thermal gas mass flow meters developed based on MEMS (Micro-Electro-Mechanical Systems) sensor chips. Its core principle utilizes the dependence of flow gas heat transfer and mass transfer: generating temperature changes upstream and downstream of the sensor to obtain the gas mass flow.

When the chip is in operation, a stable temperature field distribution is formed around the sensor; when a certain mass of gas flows through, the flow disrupts this temperature field distribution, forming a specific temperature field change depending on the gas mass and velocity. Sensors on the chip measure this change, which is then amplified, conditioned, and linearized through dedicated circuits to directly output high-quality mass flow or total flow. This design eliminates the need for temperature and pressure compensation, ensuring high-precision metering while achieving synchronization of heat source generation and temperature measurement.

The product has a compact structure and is lightweight (approx. 71g~74g). Mechanical interfaces are flexible (BST1/4, R1/4, Quick-connect 4mm/6mm/8mm optional), supporting bayonet-type rapid installation and conversion. The display uses a 4-digit 7-segment LED digital tube with 2 indicators, which can simultaneously display instantaneous flow (SLPM, standard L/min) and cumulative flow (SL, standard L). The display resolution is fine (0.001/0.01/0.1 optional). Functions include three-button operation, zero-point drift control, and low output drift (±0.12%/℃).

While retaining the core MEMS reliability, Nexisense strengthens industrial IoT integration: optional RS485/RS232 digital output supports host computer querying and parameter settings; analog voltage output facilitates traditional PLC connection; power supply 8-24VDC, low power consumption 50mA. System integrators can easily network it to achieve digital management and traceability of micro-gas flow; engineering contractors can quickly deploy it in projects such as medical respiratory equipment, gas mixing, environmental sampling, and laboratory analysis, ensuring a stable, efficient, and low-maintenance metering process.

The standard calibration gas for this series is Air (20℃, 101.325kPa). It supports multiple gas media selection, with a maximum working pressure of 0.5MPa and working temperature of -10~55℃, making it an ideal choice for precision metering of low-velocity gas in small diameter pipes.

Main Advantages

The Nexisense MF-4000 series gas mass flow meter has been optimized in MEMS chips, signal processing, and interface design, highlighting stability, high precision, anti-interference capability, and easy integration to meet the rigorous requirements of B2B projects for micro-gas metering.

1. MEMS Thermal Mass Sensing Principle & High Precision: Utilizes MEMS chip integrated multi-sensor technology, with a turndown ratio of 100:1, accuracy of ±(1.5+0.2FS)%, and repeatability of 0.25%. It has high sensitivity, starting metering even at extremely small initial flows without temperature and pressure compensation, avoiding errors caused by changing working conditions in traditional instruments. Zero-point output drift is ±30mV, and output drift is ±0.12%/℃, providing excellent long-term stability.

2. Low Pressure Loss & Fast Response Characteristics: Maximum pressure loss is only 100Pa (3mm diameter) or 600Pa (8mm diameter), with minimal impact on process piping. The default response time is 10ms, which can be flexibly set (20/50/100/200/500/1000ms), suitable for process control and sampling applications requiring fast feedback.

3. Flexible Interfaces & Easy Installation:

• Rich mechanical interfaces: BST1/4 (R1/4), 4mm/6mm/8mm quick-connectors optional, supporting easy conversion.

• Electrical interface: 5-pin Nanshi CD R-5 socket, standard wiring included for easy field connection.

• Compact structure (dimensions approx. 98mm×48mm×18mm), lightweight (71g~74g), simple installation, suitable for tight spaces or portable equipment integration.

4. Multi-output Methods & IoT Easy Integration:

• Flexible output: Linear analog voltage 0.5-4.5VDC (Standard), RS232/RS485 digital output (Optional), 4-digit LED display.

• RS485/RS232 supports host computer querying of instantaneous flow, cumulative flow, and other data, facilitating connection to industrial IoT platforms or automation systems.

• Three buttons operate intuitively, supporting parameter setting and querying; LED display is clear with indicators for convenient field observation.

• Low power design (8-24VDC, 50mA), strong anti-interference capability, adapted to industrial environments (humidity <95%RH, non-icing, non-condensing).

These advantages upgrade the Nexisense MF-4000 series from a traditional micro-flow meter to a smart metering node, helping users reduce installation costs and improve control precision and system compatibility.

Technical Specifications

Nexisense MF-4000 series gas mass flow meter main technical parameters:

Standard calibration gas: Air (20℃, 101.325kPa)

Application

Nexisense MF-4000 series micro gas flow meters are suitable for the following precision micro-flow scenarios:

1. Medical & Respiratory Equipment: Flow control of medical gases such as Oxygen, Air, and Nitrous Oxide, utilizing high sensitivity and low pressure loss characteristics to ensure safe and accurate metering.

2. Laboratories & Gas Analyzers: Sampling and mixing of analytical gases such as Nitrogen, Argon, and Carbon Dioxide, supporting RS485 connection to host computers for automatic data recording and calibration.

3. Process Control & Gas Sampling: Micro-flow monitoring of industrial processes and environmental atmospheric sampling. Portable installation and fast response are suitable for field operations.

4. Semiconductor & Electronics Manufacturing: Precision delivery of shielding gases and process gases. Wide turndown ratio meets varied working condition requirements.

5. Environmental Monitoring & Scientific Research: Micro-flow gas detection and leak testing, supporting cumulative flow functions and multiple output integrations.

6. Gas Proportionality & Equipment Testing: Used as a standard metering tool for gas mixing systems or equipment performance verification. LED display is convenient for field observation.

Wiring and Installation

Installation and wiring tips (refer to the product manual for details):

• Mechanical Installation: Choose the appropriate interface (BST1/4, R1/4, or quick-connect), ensure the gas flow direction matches the arrow, and install in a straight pipe section to avoid turbulence.

• Electrical Wiring (5-pin Nanshi CD R-5 socket):

• Pin 1 (Blue): TX / RS485 B

• Pin 2 (Green): Vout (Analog voltage positive)

• Pin 3 (Red): VCC (8-24VDC Power positive)

• Pin 4 (Black): GND

• Pin 5 (Yellow): RX / RS485 A

• Confirm correct wiring before powering on (standard 50cm wiring provided, plug on one end and loose wires on the other). Slowly introduce gas to perform zero-point check.

• Operation: Set parameters, switch between instantaneous/cumulative flow display, and query data via the three buttons.

• Maintenance: Regularly check interface seals and ensure no mechanical damage. MEMS chips have no moving parts, making daily maintenance simple.

When using for high-pressure or special gas applications, please confirm model compatibility and comply with safety regulations.

FAQ

Q1. What is the core principle of the Nexisense MF-4000 series micro gas flow meter?
Based on MEMS thermal mass flow metering, it utilizes the principle that gas flowing through the sensor disrupts the stable temperature field distribution to directly measure mass flow without temperature and pressure compensation.

Q2. How to choose the diameter and maximum flow rate for different models?
MF-4003 (3mm) is suitable for ultra-small flow (up to 5 SLPM); MF-4008 (8mm) is suitable for larger micro-flow (up to 50 SLPM). Selection depends on pipe diameter and requirements.

Q3. What output methods are supported? Can RS485 be integrated into a PLC system?
It supports analog voltage 0.5-4.5VDC (Standard), and RS232/RS485 (Optional). RS485 facilitates Modbus integration for host computer data querying and automation control.

Q4. Which gas media are suitable? Can Oxygen and Carbon Dioxide be measured?
It supports multiple gases including Air, Nitrogen, Oxygen, Argon, Carbon Dioxide, and Nitrous Oxide (media codes A/B/C/N/O/R must be specified during selection). Please confirm specific compatibility.

Q5. How do the pressure loss and response time perform?
The pressure loss is extremely low (100~600Pa), and the response time is 10ms (adjustable), suitable for applications sensitive to pipeline impact or requiring fast response.

Q6. Are the installation interfaces and wiring convenient?
It supports multiple threads and quick-connectors. The 5-pin standard socket wiring is clear, and button operation is simple, suitable for rapid installation and field use.

Q7. What are the display and functions? Can it display cumulative flow?
The 4-digit LED displays instantaneous SLPM and cumulative SL, with adjustable resolution. It supports parameter querying and button operations.

Q8. What are the working environment requirements and maintenance precautions?
Working temperature -10~55℃, humidity <95%RH. Keep the gas clean and regularly check the interfaces; no complex maintenance is required.

Summary

Nexisense MF-4000 series gas mass flow meters take MEMS thermal mass sensing technology as the core. With high-precision micro-flow measurement, extremely low pressure loss, fast response, multiple output methods, and flexible interfaces, they provide a professional and reliable micro-gas metering solution for system integrators and engineering contractors. It effectively solves the metering challenges of low-velocity gas in small diameter pipes, ensuring data accuracy, convenient installation, and seamless system integration.

Whether in oxygen control for medical equipment or gas analysis and process sampling in laboratories, the Nexisense MF-4000 series can become the stable cornerstone of your precision metering system.

Need specific model guidance (media, output, interface), Modbus communication details, dimension confirmation, or project quotation support?
Welcome to contact the Nexisense technical team. We will provide targeted recommendations and complete technical solutions based on your pipe diameter, flow range, gas type, output requirements, and integration method. Act now to make micro-gas flow metering more accurate, stable, and intelligent.