Skip to content

Adding CO2 to MSR-2

You'll slide your sensor out of its case, fit the SCD40 module onto its mezzanine connector, and put the case back together.

1. Unplug your MSR-2 from power and remove the back

Back of the MSR-2 case with the Apollo logo backplate in placePressing on the edge of the MSR-2 backplate to pop it off the caseMSR-2 with the backplate removed, showing the board inside the case

2. Flip the MSR-2 upside down and gently tap the case on the table and your MSR-2 should slide out of the case.

MSR-2 case flipped upside down with the backplate offLifting the case off the MSR-2, showing the MSR-2 Rev 9 boardMSR-2 board sliding out of its case, with the mmWave module on top

3. With the case removed, identify the bottom right corner where the small black mezzanine connector lives. You will see an "X" indicating which corner needs to be lined up with the SCD40 CO2 sensor. There is an X on the SCD40 sensor's PCB as well, you can see it in the image below but it is slightly cut off on the PCB itself. There is also a "gold dot" in the top left of the SCD40 when oriented properly.

MSR-2 Rev 9 board with the black CN1 mezzanine connector and the X marking beside itSCD40 CO2 sensor lined up below the CN1 connector on the MSR-2 board

4. Gently push the SCD40 CO2 module onto the black mezzanine connector.

Pressing the SCD40 CO2 module onto the mezzanine connector on the MSR-2 boardSCD40 CO2 module seated on the MSR-2 board beside the ESP32 module

5. Slide the case back over the MSR-2, making sure that the case has the hole for the USB-C port facing the right direction.

Sliding the case back over the MSR-2 boardEnd of the MSR-2 case with the USB-C port showing through its opening

6. Gently press the backplate of the MSR-2 case onto the MSR-2 until it lightly snaps into place. Please do not force it, if necessary please repeat steps above until it seats in the case without any force required.

Pressing the backplate onto the MSR-2 case until it snaps into place

7. Please refer to our CO2 calibration guide to calibrate the CO2 module after installation. This is required for all CO2 addons purchased from us separately from a product (such as buying it to add on to an existing Apollo device).