Connect Sensors

Use the short (50mm length) STEMMA QT cables to connect the various sensors together.

Use the longer (100mm length) STEMMA QT cable to connect the QT Py ESP32-S3.

Install QT Py

Orient the QT Py's USB-C Port with the mounting tabs on 3D printed holder.

Insert the QT Py into the holder at an angle so one side of the PCB are fitted under the corner tabs.

Then, slightly flex the holder to allow the other side of the PCB to fit under the corner tabs.

Installed QT Py

Check the PCB is fitted under all four corners on the 3D printed holder. 

Take a moment to ensure the QT Py is in the correct orientation and the STEMMA QT cable is connected.

Secure QT PY Holder

Place the QT PY holder over two mounting holes on the QT Py mounting plate (either side, holes are symmetrical).

Insert and fasten two M3 x 6mm long screws. Secure the parts together using M3 hex nuts.

Sensor Mount

Get the 3D printed sensor mount, sensors and hardware screws ready to assemble.

• 6x M2.5 x 6mm long machine screws

Secure SCD40

Place the SCD40 sensor onto the standoffs on the sensor mount. Reference the photo for the correct orientation

Insert and fasten two M2.5 x 6mm long machine screws to secure the SCD40 to the sensor mount.

Secure MLX90632

Place the MLX90632 sensor onto the standoffs on the sensor mount. Reference the photo for the correct orientation.

Inert and fasten two M2.5 x 6mm long machine screws to secure the MLX90632 to the sensor mount.

Secure VEML7700

Place the VEML7700 sensor onto the standoffs on the sensor mount. Reference the photo for the correct orientation.

Inert and fasten two M2.5 x 6mm long machine screws to secure the VEML7700 to the sensor mount.

Secured PCBs

Take a moment to ensure the various PCBs have been properly secured to their 3D printed mounts.

Use the following hardware to secure the QT Py mounting plate to the sensor mount.

• 2x M3 x 6mm long machine screws

Attach Mounting Plate

Place the QT Py mounting plate to the mounting tab on the sensor mount with the two mounting holes lined up.

Double check the orientation of the parts are correct following the assembly photo.

Insert and fasten two M3 x 6mm long machine screws to secure the parts together.

Connect QT Py to Sensors

Plug in the STEMMA QT cable from the QT Py to the available port on the SCD40 sensor.

Double check the placement of all the sensors and QT Py are in the correct orientation.

Install Sensors to Case

Orient the 3D printed case with the sensor mount assembly.

Insert the sensor mount assembly into the case with the four mounting holes lined up.

Double check the orientation of the parts are correct.

Install Bottom Cover

Use the following hardware to secure the bottom cover to the case.

• 4x M3 x 16mm long machine screws

Secure Bottom Cover

Orient the bottom cover with the various sensors so the cutouts are lined up with the components.

Insert and fasten the four M3 x 16mm long machine screws to secure the bottom cover to the sensor mount and case.

Install Top Cover

Use the following hardware to secure the top cover to the case.

• 4x M3 x 6mm long machine screws

Secure Top Cover

Orient the top cover with the QT Py's USB-C port and place it onto the case with the four mounting holes lined up.

Insert and fasten the four M3 x 6mm long machine screws to secure the top cover to the case.

Install Hook

Insert a hook or elastic cord to the attachment hole on the top cover.

USB Power

Connect the USB-C cable to the QT Py. Then, connect the USB-C cable to a 5V power supply.

Hanging Grow Monitor

Depending on your setup, you'll want to decide how to suspend your grow monitor over your plant. Ideally, the sensors should be position above your plant.