DFRobot Gravity STCC4 True Carbon Dioxide Sensor (3-in-1 Air Quality Monitoring, 400-5000ppm) - Gravity I2C

True CO₂ measurement, as used by the STCC4's Thermal Conductivity (TC) technology, directly quantifies carbon dioxide molecules. In contrast, eCO₂ (equivalent CO₂) sensors often estimate concentration based on VOC levels, which can be less accurate in environments with variable air composition. The TC method provides more reliable and stable readings for genuine air quality assessment.

Connect the sensor's Gravity 4-pin cable to your Arduino's I2C pins (SDA, SCL, VCC, GND). Ensure the Arduino is powered within the 3.3V to 5V range. Use the dedicated DFRobot STCC4 library to initialize the sensor and read CO₂ concentration, temperature, and humidity values directly via simple I2C commands.

The sensor features Automatic Self-Calibration (ASC), which periodically adjusts its baseline in environments assumed to have periodic exposure to fresh air (around 400 ppm CO₂). For best results, install the sensor in a location with regular air exchange. Manual calibration is not typically required, but the ASC algorithm can be configured or disabled via the sensor library if needed.

Yes, it is suitable for battery operation. In continuous measurement mode, it draws approximately 950 µA. For ultra-low power applications, utilize the single-shot mode (100 µA with a 10-second sampling interval) or deep sleep mode (1 µA). This makes it ideal for portable air quality monitors and long-term IoT deployments.

This sensor is designed for indoor air quality monitoring within its specified operating range of 10°C to 40°C and 20-80% RH (non-condensing). It is not rated for outdoor use, extreme temperatures, high humidity, or corrosive industrial atmospheres. For such applications, a hardened industrial transmitter with appropriate IP ratings is recommended.