node-red-contrib-scd30

Node-RED node for reading measurements from Sensirion SCD30, the CO2, temperature, and humidity sensor.

Uses scd30-node.

Usage

Find the scd30 node in the sensor category in the palette, and use in your flow.

The node replaces the message payload with an object containing the measured values:

{
  co2Concentration: <number>,
  temperature: <number>,
  relativeHumidity: <number>
}

Requirements

The SCD30 must be in continuous measurement mode and a measurement must be available when triggering this node. You can use scd30-cli to set this up:

$ scd30-cli start-continuous-measurement
Continuous measurement started.
Ambient pressure compensation deactivated.

$ scd30-cli set-measurement-interval 5
Continuous measurement interval set to 5 seconds.

The measurement interval must be shorter than the interval at which you sample the sensor in Node-RED.

The permission to read the I2C bus device (e.g. /dev/i2c-1) is required.

Usage in Docker on Raspberry Pi

When starting the Node-RED container, use these options:

• --device /dev/i2c-1 – point to the I2C device to which the SCD30 is connected
• --group-add <id of i2c group> – make the container process run as a member of the i2c group

For example:

docker run -d \
  -p 1880:1880 \
  -v /home/pi/.node-red:/data \
  --device /dev/i2c-1 \
  --group-add 998 \
  --name nodered \
  nodered/node-red