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AMo - CO2 Monitor§

How to use and configure the ThingPulse AMo CO2 monitor.

Using the AMo§

The AMo is a true plug & play device. Connect it to a power source through the Micro-USB connector, turn it on, and you are good to go. The premium CO2 sensor will self-calibrate within a couple of minutes.

The 10second manual: use the push button on right side to turn off/on acoustic warning.

Read on for the full manual.

CO2 readings on display§

The way the measured CO2 readings are displayed is specifically tuned to the characteristics of the 8x8 LED display. The values displayed by the AMo are 1/1000 of the actual reading rounded to 1 or 2 fractional digits omitting the leading 0. Consequently, the AMo will always display 2 digits in total (see examples below).

CO2 is measured in "ppm", parts per million. Following the start of the Industrial Revolution, atmospheric CO2 concentration increased to over 400 parts per million and continues to increase (causing the phenomenon of global warming). Hence, during normal operation you will not see readings below 400ppm.


  • 603ppm → .60
  • 613ppm → .61
  • 615ppm → .62
  • 994ppm → .99
  • 995ppm → 1.0
  • 1249ppm → 1.2
  • 1250ppm → 1.3

Monitoring CO2 levels & alerting§

The AMo uses a monitoring approach borrowed from traffic lights. Depending on the level of CO2 the background color on the display changes from green to yellow and then to red. In addition, at the yellow and red stages the screen flashes slowly or quickly respectively. On top of that the integrated speaker beeps every 10s when CO2 concentration reached the red level. See table below.

There is an ongoing scientific debate as to what the "healthy" indoor CO2 range is i.e. at what level you should ventilate your office, classroom, restaurant, etc. As long as clear guidelines are missing ThingPulse decided to configure the AMo with conservative (i.e. cautious) defaults.

Side note: effects of too much CO2 (or too little oxygen actually) include fatigue and headache.

CO2 color display flashing acoustic warning
<850ppm green - -
850-1000ppm yellow slow -
>1000ppm red quick every 10s

Turning off acoustic alerting§

We understand that in certain environments it may be undesirable to disturb occupants with acoustic alerts. Using the push button on the right side allows to turn it off - and on again. After pushing the button the AMo will briefly display one of the two speaker icons below to indicate whether acoustic alerting is off or on.

acoustic alerting off acoustic alerting on

Mobile apps§

AMo is a fully compliant Sensirion Smart Gadget. Install the MyAmbience app for iOS and Android to visualize and monitor sensor data on your mobile device.

MyAmbience app

download from App Store download from Play Store

Configuring the AMo§

Should you want to adjust the monitoring levels, LED brightness or speaker volume you can download and run the ThingPulse App Fairy application. It will completely replace the existing firmware with the one you configured in the App Fairy.


Proceed with caution! Although the process is fairly simple and robust malfunctions can not be ruled out. Reach out to us if you get stuck.

  • As a precondition please install the Silicon Labs Serial-to-USB driver on your computer or Mac.
  • Connect the AMo to your computer or Mac over USB and turn it on.
  • Start the App Fairy.
  • Select "Icon64" as device type and "CO2 Monitor" as application.
  • In the configuration dialog enter scd4x for sensor type