SCD41 CO2 Sensor Breakout (Carbon Dioxide / Temperature / Humidity)

by Pimoroni

A true carbon dioxide sensor that can detect CO2 levels between 400 and 5,000 ppm, mounted on a Breakout Garden and Qw/ST-compatible breakout.

SCD41 is a high accuracy sensor that uses photoacoustic technology to tell you the precise proportion of carbon dioxide (in ppm) of the air that you're breathing. It can also measure temperature and relative humidity.

Too much carbon dioxide has all sorts of unpleasant effects on humans, such as turning up your tiredness levels and turning down your brain power. CO2 build-up is a useful indicator of how well ventilated a space is and also how many people are breathing the same air - a variable that's definitely worth tracking in homes, workplaces and schools at the moment. SCD41 is the extended range variant of this sensor which means it can detect very high levels of CO2 at up to 5,000 ppm, so it could potentially also be useful in industrial and laboratory settings.

We've been testing out this sensor in some of the more confined scuppers and bilges of Pimoroni HQ, and it's remarkable how sensitive it is - you can really see the change in CO2 levels when someone enters or leaves a room, or when doors are open or closed.

This breakout is compatible with our fancy Breakout Garden system, where using breakouts is as easy just popping it into one of the slots and starting to grow your project, create, and code. It's also Qw/ST compatible so it can be plugged into a whole range of different microcontrollers and HATs with Qwiic or STEMMA QT connectors.

Features

  • Sensiron SCD41 carbon dioxide sensor (datasheet)
    • Photoacoustic sensor technology PASens®
    • High accuracy: ±(40 ppm + 5 %)
    • Range: 400 ppm – 5,000 ppm
  • I2C interface, with address: 0x62
  • Qwiic/STEMMA QT connector
  • 3-5V compatible
  • Reverse polarity protection (on Breakout Garden connector)
  • Raspberry Pi-compatible pinout (pins 1, 3, 5, 7, 9)
  • Compatible with Raspberry Pi (Python library)
  • Compatible with Raspberry Pi Pico (C++/MicroPython libraries)
  • Schematic

Kit includes

  • SCD41 breakout
  • 1x5 male header
  • 1x5 female right angle header

We've designed this breakout board so that you can solder on the piece of right angle female header and pop it straight onto the bottom left 5 pins on your Raspberry Pi's GPIO header (pins 1, 3, 5, 7, 9). The right angle header also has the advantage of positioning the breakout away from the Pi's CPU so as to minimise radiated heat.

Software

We've put together a Python library together with examples showing you how to get readings from the sensor. 

You can also use this breakout with Raspberry Pi Pico and other RP2040 boards, using C++ or Pirate brand MicroPython.

Notes

  • Dimensions: approx 24mm x 21mm x 8mm (L x W x H, including sensor)

11 customer reviews

3 years ago
The SCD41 proved to be a very reliable CO2 sensor during the past weeks that I tested it thoroughly in different environments and conditions. Unlike metal-oxide gas sensors, which I also tested, they produced idiot values when the humidity of the room suddenly changes (in case the door to the shower is opened or a window) or goes totally bananas when people are consuming alcoholic beverages in the room with the sensor. This is NOT the case with the SCD41, it gives values that make sense! 👍
by Marcel about SCD41 CO2 Sensor Breakout (Carbon Dioxide / Temperature / Humidity) via REVIEWS.io
3 years ago
他のメーカーからもSCD41を使った製品は出ていますが、pimoroniのBreakout Gardenは全体的に黒と金で統一されており、私の好みに合っていて、他の黒い部品と一緒に使うと全体的な統一感が出ます。センサーの精度も今まで使っていたeco2とは全く別物なくらい精度が良く、非常に気に入っています。
by Anonymous about SCD41 CO2 Sensor Breakout (Carbon Dioxide / Temperature / Humidity) via REVIEWS.io
3 years ago
Superb but slightly expensive sensor. Not a calibrated instrument but it provides a excellent view of CO2, temperature and humidity. Easy to install and to read from Python. A few lines of code cut and paste from examples on Pimoroni website. Build your own monitor / logger for less than £100. Just need availability on Pi models.
by james about SCD41 CO2 Sensor Breakout (Carbon Dioxide / Temperature / Humidity) via REVIEWS.io

2 user photos