Gas metering solutions
Experts in flow sensing

Thermal-mass modules forsmart gas metering
Sensirion gas meter modules are based on the thermal-mass measurement principle, which is the best technology tomeasure flow to date and is used in high volumes in a wide range of challenging key applications in automotive, medical
and industrial sectors. Sensirion’s ­success is due to the proven CMOSens® Technology, which combines the sensor andanalysis electronics on a single semiconductor chip. This technology provides excellent sensing performance and robustness at ultra-low power consumption and attractive costs.

Thermal-mass measurement
principle

HeaterAt the heart of every Sensirion gas meter module is a
MEMS-based calorimetric microsensor, which measures

Gas flow

the flow of natural gas using the thermal-mass measurement principle. The sensor element is located on a membrane and consists of a micro-heater and upstream anddownstream temperature sensors. It is integrated withthe signal conditioning electronics, including memory forcalibration data, on a single CMOSens® chip.

Temperature sensors

Silicon

1 mm

EN 17526
EN 14236

Hydrogen-ready with Sensirion

Evaluation
certification

The use of hydrogen for energy storage and distribution
purposes requires the key components of the existing

0IML R 137

gas infrastructure to be adapted. This infrastructure
includes gas meters, which must be able to measure natural gas, hydrogen blends and eventually pure hydrogen.
It is highly desirable to futureproof a meter and make it
ready for this transition today to prevent any need formeter replacement when pure hydrogen enters the pipes.
Gas meters incorporating thermal-mass gas meter modules are the ideal candidates for this task. Thanks to theunique measurement principle, the same thermal-mass

Evaluation certificate

sensor can measure natural gas, LNG, hydrogen blends

Sensirion’s standard gas meter modules have achievedand pure hydrogen (alongside biomethane). This is despite

an evaluation certification in accordance with the harmo-

the three times higher hydrogen flow rates required com-

nized standard EN 14236 and the normative document

pared to natural gas (e.g. G4 meters have Q max of 6 m3/h

OIML R 137 (EN 17526 from 2022). The evaluation certificate

for natural gas and 20 m3/h for hydrogen to compensate

is issued by NMi, one of the leading notified b­ odies infor hydrogen’s calorific value that is three times lower). It

Europe for type approval examination and certification ofis a unique feature, which cannot be easily implemented

measuring instruments. The evaluation certificate enables

with a diaphragm or other static metering technologies,

easier and faster MID approval for gas meter manufac-

which either have to be tripled in size or require additional

turers that use Sensirion’s thermal-mass sensor modules

complexity and cost for high hydrogen contents.

as the core metrological unit in their gas meters.

Thermal-mass technology –key features
Established technology

Detect leakages

Proven by over 6 million meters in the field, billions of hours

Equip your meter with leak detection functionality, thanksof reliable metering and independent laboratory tests after

to ultra-low flow sensitivity and the sensor’s absolute

10 years of field installation.

pressure output.

Natural gas and H2-readyLower certification costs

Ready for the future and any gas mixture, including ­naturalSave 30% of your meter certification costs thanks togas types H, L and E, LNG, H2 blends, pure H2 and b­io-­sensor evaluation certification according to EN 14236 andmethane.

OIML R 137 (EN 17526 from 2022).

Cut battery costs

A clear H2 ratio in the gas

Thanks to ultra-low power consumption of < 105 mAh/year.

The module can determine the H2 ratio in the gas mixture.
This information can be used for grid monitoring purposes,
shared with environmentally conscious consumers, andused for connected appliances.

Zero service costs
No more need for meter recalibration, thanks to zero offset and zero sensor drift. No moving parts mean no wear
and tear.

Tamper-proof and smart
Enable smart features like tampering detection, self-diagnostics and grid analytics.

Compact static meter and lower logistics costs

Competitive on costs

Thanks to a highly compact size and no moving parts. TheThanks to a streamlined design, high-volume production

meter size is independent of the H2 content.

and a high level of integration on a semiconductor chip.

No need for a volume converter

Trend toward energy metering

Sensors output volume flow referred to standard tempera-This forms the foundation of natural gas energy content

ture and pressure (standard m³/h).

monitoring being implemented in the future. The sensors
can estimate the gas calorific value even today.

Class 1.5 gas meter modules
Sensirion offers gas meter modules for residential andindustrial smart gas metering applications. They fulfill
MID accuracy class 1.5, and are available for gas metersizes G1.6 to G25. They feature a digital I2C interface andare fully calibrated for air and natural gas.
Sensirion’s gas meter modules have achieved an evaluation certification in accordance with the harmonized standard EN 14236 and the normative document OIML R 137(EN 17526 from 2022) for natural gas containing up to23% H2 (e.g. limit gas G222 according to EN 437). The­latest products can also measure up to 100% H2.

Specification of flow ranges
Parameter

G1.6

G2.5

G4G6

G10G16G25Unit

Qmin

0.016

0.025

0.040

0.060

0.100

0.160

0.250

m3/h

Qt

0.250

0.400

0.600

1.00

1.60

2.50

4.00

m3/h

Qmax

2.50

4.00

6.00

10.0

16.0

25.0

40.0

m3/h

Qstart< 1⁄4 Qmin

Qoverflow

2 Qmax

Qreverse– 0.2 Qmax

Physical specifications
Parameter

DescriptionValue

UnitTemperature

Operating temperature–25 to 55°C

Humidity

Operating humidity in natural gas

0 to 40% RH

Flow range: Qreverse ≤ Q ≤ -Qmin± 10% m.v.

Flow range: Qmin ≤ Q < 0.1Qmax± 3.0 (+0.5)% m.v.

Flow range: 0.1Qmax ≤ Q ≤ Qmax

± 1.5 (+0.5)% m.v.

Pressure drop at Qmax

< 1.0mbar in air

Accuracy (for T = 15°C)

Initial pressure drop without meter housing

Electrical specifications
Parameter

ValueUnit

Operating voltage

2.7 to 3.6

Vdc< 12µA< 105

mAh/year

Average current consumption (approx.)1
Electrical interface

I2C

1 Exact current consumption depends on the exact electronic host environment.

Complete design-in solution
Sensirion provides a support package to enable fast and easy integration of Sensirion gas meter modules
into customer gas meter products.

Sensirion gas meter modules

Evaluation certification

Complete documentation

Make use of the Sensirion evaluation certificate to gain

Integrate Sensirion gas meter modules into gas meterMID approval faster and more easily for gas meter prod-products quickly and efficiently, thanks to comprehensive

ucts that use Sensirion gas meter modules as the core

documentation.

metrological unit.

Evaluation kit

Electronic reference design

Perform a basic technology evaluation of Sensirion

Use the Sensirion electronic board, including sample

thermal-­mass gas modules using the convenient evalua-code, as a reference during implementation of the sensor-­tion kit, including readout software.

relevant firmware code for a thermal-­mass gas meter.

Benchtop measurement setup

Partner networkPerform flow characterization of Sensirion gas meter

Benefit from Sensirion’s partner network in the gas meter

modules with Sensirion’s compact R&D benchtop setup

component industry.

for flow measurement.

Technology at heart,
future in mind.

www.sensirion.com