WINSEN · CO₂ SENSOR MODULE

Winsen MH-Z19B

Manufacturer-verified NDIR CO₂ sensor module. Specifications below are taken from Winsen’s official product information.

NDIRCO₂UART · PWM

Key Specifications

MODELMH-Z19B
MEASUREMENT TECHNOLOGYNon-dispersive infrared (NDIR)
MEASURED GASCO₂
MEASUREMENT RANGE400–2,000 / 5,000 / 10,000 ppm
ACCURACY±(50 ppm + 5% reading)
RESPONSE TIMET90 <120 s
PREHEAT TIME3 min
POWER SUPPLY4.5–5.5 V DC
CURRENT<20 mA avg · 150 mA peak
INTERFACES / OUTPUTSUART · PWM
OPERATING RH0–95% RH non-condensing
OPERATING TEMPERATURE−10–50 °C
WEIGHT5 g
LIFESPAN>5 years
Specification note: Measurement range and accuracy can depend on the selected variant. Verify the ordered model and current Winsen datasheet before integration.

Product Positioning

Winsen MH-Z19B is an NDIR CO₂ sensing product from Winsen intended for OEM gas measurement and system integration.

Official Resources

For integration and purchasing decisions, verify the current documentation directly with Winsen.

View Winsen MH-Z19B Official Page

AirAlign is an independent informational resource and is not affiliated with Winsen. Manufacturer documentation remains authoritative.

MH-Z19B — legacy NDIR integration differences

MH-Z19B is a UART/PWM NDIR CO₂ family with 400–2,000, 5,000 or 10,000 ppm range options and a longer listed preheat than the MH-Z19C example. Verify physical connector, serial commands, PWM period and selected range before replacing a B or C revision. The quoted ±(50 ppm + 5% of reading) figure should be interpreted under its original conditions and calibrated baseline assumptions. The 4.5–5.5 V supply and non-condensing exposure requirement should be included in an OEM board and enclosure design.

Winsen MH-Z19B — discontinued NDIR module, avoid new-design promotion — model evidence and engineering selection

Current original manufacturer information differentiates optical design, gas span, data interfaces, revision-specific power and calibration assumptions.

CharacteristicSource-backed detailSelection consequence
LifecycleWinsen marks the MH-Z19B model discontinuedTreat as installed-base repair or legacy reference, not active new production.
Measurement principleTemperature-compensated NDIR CO₂; non-oxygen-dependent optical processDoes not detect O₂ or flammable gas.
Span choices400–2,000/5,000/10,000ppm order variantsSelection is model configuration, not guaranteed precise 0–10kppm on any used sensor.
Maker uncertainty±(50ppm +5% reading)At 1,000ppm nominal expression ≈±100ppm, not the newer S12’s ±60ppm.
Electrical supply4.5–5.5V DC, <20mA average and about 150mA peakHost regulator and logic-level UART must handle emission pulse.
Signal formats3.3V UART (5V-compatible I/O stated by maker) and PWMNo native analog 4–20mA or isolated Modbus RS485 industrial transmitter.
Startup / gas stepThree-minute preheat and T90 <120sDo not substitute a newer MH-Z19C performance figure.
Environment−10 to +50°C, 0–95%RH noncondensing, 32.9×19.7×8.6mmField condition and optical aging require calibration and availability checks.

Firmware, operating environment and calibration

The official supplier now labels MH-Z19B discontinued. AirAlign retains this page so existing hardware can be serviced without confusing MH-Z19B with successor-series devices. Test firmware protocol, PWM scaling, pressure/temperature compensation and the ABC calibration algorithm before substituting a Z19C or Z19D; similar footprints do not prove direct command/behavior equivalence. The initial three-minute preheat is important for ventilation control: do not treat first powered measurements as stabilized truth. For always-high-CO₂ rooms, fresh-air ABC assumptions require special handling.

Original model source: Manufacturer technical model and its current product documents. Use current production suffix and calibrated configuration, not a parent-family estimate.

AirAlign editorial engineering review — 25 October 2026. OEM facts are not independent safety, media license or exact SKU procurement approval.