Marmonix MTF-4100 Thermal Mass Flow Meter for Hydrogen

The Marmonix MTF-4100 hydrogen thermal mass flow meter reads gas mass flow directly with two platinum resistance sensors, one heated and one tracking gas temperature, so no separate pressure or temperature compensation is needed. Published figures: 0.5–100 Nm/s velocity range, ±1% of reading as an inline pipe meter (DN10–DN2000) or ±2.5% as an insertion probe (DN80–DN4000), 1 s response, sensor rated −40 to +220 °C, and pressure up to 4.0 MPa inline or 2.5 MPa insertion. It provides 4–20 mA and pulse outputs, RS485 or HART, one or two relay alarms and a four-line LCD. The wider Marmonix flow meters range covers other gases too, including the MTF-4300 nitrogen thermal flowmeter for N₂ service.

Thermal Mass Flow Meter flor Hydrogen MTF-4100

Thermal Mass Flow Meter flor Hydrogen MTF-4100 is designed on the basis of thermal dispersion, and adopts method of constant differential temperature to measuring gas flow. It has advantages of small size, easy installation, high reliability and high accuracy, etc.
The meter contains two platinum resistance temperature sensors. The thermal principle operates by monitoring the cooling effect of a gas stream as it passes over a heated sensor. Gas flowing through the sensing section passes over two sensors one of which is used conventionally as a temperature sensor, whilst the other is used as a heater. The temperature sensor monitors the actal process values whilst the heater is maintained at a constant differential temperature above this by varying the power consumed by the sensor. The greater the gas velocity, the greater the cooling effect and power required to maintain the differential temperature. The measured heater power is therefore a measure of the gas mass flow rate..

Thermal Mass Flow Meter flor Hydrogen MTF-4100 Features

Measurement and integration features of the MTF-4100:

• Measuring the mass flow or volume flow of gas
• Do not need to do temperature and pressure compensation in principle with accurate measurement and easy operation
• Wide range: 0.5Nm/s~100Nm/s for gas. The meter also can be used for gas leak detection
• Good vibration resistance and long service life. No moving parts and pressure sensor in transducer, no vibration influence on the measurement accuracy.
• Easy installation and maintenance. If the conditions on site are permissible, the meter can achieve a hot-tapped installation and maintenance. (Special order of custom-made)
• Digital design, high accuracy and stability
• Configuring with RS485 or HART interface to realize factory automation and integration

Thermal Mass Flow Meter flor Hydrogen MTF-4100 Specifications:

How thermal mass flow meters are used on hydrogen gas lines

Hydrogen feeds processes such as heat-treatment atmospheres, chemical reactions, generator cooling and fuel-cell or electrolyser test rigs. Operators want to know how much gas is consumed, often at low flow rates where mechanical meters struggle.

A thermal dispersion meter measures the heat a moving gas carries away from a heated sensor, so the result depends on the gas’s heat-transfer properties. Hydrogen conducts heat far better than air, and thermal meter makers such as Fluid Components International note that converting an air set-up to hydrogen with generic gas factors is not adequate. The gas must therefore be named at order so the meter is set up for actual hydrogen.

Hydrogen is also flammable, and many hydrogen areas are classified as hazardous. Before installation, the site checks its zone classification against the meter’s rating, fits the probe with the recommended straight run, and wires the 4–20 mA or RS485/HART signal to the control system for totalising and alarms.

Questions about the MTF-4100 hydrogen flow meter

Why use a thermal mass meter on hydrogen?

It measures mass flow directly with no moving parts and responds from 0.5 Nm/s, so low consumption is still visible. Make sure it is ordered for hydrogen, because heat transfer in H₂ differs strongly from air.

Inline or insertion: which MTF-4100 version do I need?

The inline pipe version covers DN10–DN2000 at ±1% of reading and up to 4.0 MPa. The insertion probe covers DN80–DN4000 at ±2.5% and up to 2.5 MPa; a hot-tapped insertion build is a special order. Compact units take 24 VDC or 220 VAC, remote units 220 VAC.

Is the MTF-4100 rated for hazardous areas?

The published specification lists IP65 protection and gives no explosion-proof marking. Hydrogen areas are often classified as hazardous, so share your zone classification with us before ordering so the right version can be confirmed.