Sensirion Environmental Sensor Shield - Review

Table of contents

RoadTest: Sensirion Environmental Sensor Shield - Industrial Sensing

Author: anuag_ashim

Creation date:

Evaluation Type: Development Boards & Tools

Did you receive all parts the manufacturer stated would be included in the package?: True

What other parts do you consider comparable to this product?: Other Sensor boards from Adruino

What were the biggest problems encountered?: None

Detailed Review:

Thank you element14 for choosing me for this Roadtest.

 

 

Unboxing Sensirion Environmental Sensor Shield (ESS)

 

The Sensirion Environmental Sensor Shield (ESS) is a sensor shield that features SHTC1 humidity and temperature sensor along with a SGP30 total VOC and CO2eq sensor.

The unboxing image

 

It is a small sensor board and came in its own box with a small page

 

ESS Setup with Arduino UNO

 

I have used Arduino UNO to do my tests and run the Sensirion Environmental Sensor Shield (ESS)

The Sensirion Environmental Sensor Shield (ESS) is turned On with Arduino

 

Getting Started with ESS

The The Sensirion Environmental Sensor Shield (ESS) is a sensor board with variety of sensors such as SGP30 and  on it and has plug-in pins to the Arduino board. All the sensors are readable via serial communication and  I2C bus and can be read online.

 

The sensing principle of the SGP is based on a heated film of metal-oxide (MOx) nanoparticles.

 

SGP30 on ESS Sensor

 

Specifications of the SGP30 Sensor DataSheet. The SGP30 Sensor comes in DFN package with a small footprint and a circular sensor opening of max. 1.6mm diameter on top.

Block Diagram showing SGP30 functionality

 

Specifications of SGP30 Sensor as shown above

 

Measuring the Air quality of the Sensor SGP30

 

The Moisture Sensitivity Level classification of the SGP30 is MSL1, according to IPC/JEDEC J-STD-020 standard. The SGP30 also provides on-chip humidity compensation for air quality signals CO2 and TVOC; and sensor raw data for H2-signal and Ethanol signals.

 

TVOC Sensor on ESS

 

The use of new materials has resulted in increased concentrations of volatile organic compounds (VOCs) in the air. The VOCs can come from paints and solvents, carpets and furniture, and cleaning agents, and are also emitted by humans.

Elevated VOC levels have a negative impact on well being, comfort, and cognitive abilities. Exposure to high levels of VOCs can be avoided or significantly reduced by regular ventilation and air purification.

 

The Total Volatile Organic compounds (TVOC) can be used to survey the indoor environments for contamination or to find the source of pollutants in the house. Datasheet

Typical Indoor TVOCs are above as shown

 

The German Health Department defined TVOC levels

 

TVOC applications are

  • Testing of materials for emission of chemicals.
  • Indicator of poorly designed ventilation.
  • Identifying high pollution areas and highly polluting activities.

European Commission Environment Institute Report on TVOC

 

SHTC1 Sensor IC on ESS

 

The SHTC1 is a digital humidity and temperature sensor which uses the Sensirion's CMOSens technology to offer a sensor system on a chip. This sensor chip has a capacitive humidity sensor, a temperature sensor and also does A-to-D conversion and digital signal processing. Datasheet

 

Block Diagram of SHTC1 Sensor on chip

 

Features of SHTC1 sensor is as shown above

 

Humidity and temperature specs from SHTC1

 

Typical accuracy of relative humidity measurements given in %RH for temperature range 0–80°C

 

Setup the Arduino Code Environment

 

I used the Mac OSX setup for my laptop as shown below to setup Adruino. Some simple steps to add the ESS libraries are shown below

 

 

LED Blinking Test with ESS

 

I did a simple startup test with the sample code to blink the LEDs. It can be seen in the video below.

 

 

Recording the Environment data in my home using the LED Blinking Test Sensirion Environmental Sensor Shield.

 

I used the Adruino Serial Terminal to plot the graph and all the data was taken at room temperature

 

Experimenting with Sensirion ESS

 

I am presenting some of the experiments I did with the The Sensirion Environmental Sensor Shield to test the limits of the temperature; humidity and CO2 sensors.

 

Subzero Temperature Measurement

 

For this test; I wanted to record very low temperature and see the performance of the sensor at below zero degrees. I took a frozen ice pack and placed it on top of the ESS and measured the data.

Interestingly the ESS has a very fast response time and immediately I saw the temperature drop to a very low level

I also used a cold spray to test the gradual change in temperature by giving cold air to the Temperature Sensor

 

Screenshot of the temperature curve

Live recording of the temperature sub-zero test

 

Restored temperature sensor response after removing the ice-pack

 

Here I can see clearly the temperature sensor measured value is getting restored back to room temperature from -5 deg C (from the cold pack)

 

Extreme Humidity measurement ESS

 

Here I used the same setup with ice pack to see the change in humidity before and after the ice-pack is removed. The humidity levels change drastically in this test and has been plotted below.

 

 

Live recording of the Result

 

ESS CO2 Sensor Tests with a Candle

In this test; I took a simple daily to use tea light candle and the ESS sensor. Then I used a glass bowl to completely cover the setup to avoid flow of oxygen in the bowl. After sometime; I further sealed the edges with a cloth. This allowed the candle to burn for sometime releasing the CO2 in abundance and get trapped in the bowl and reach a point where the candle goes off and the CO2 peak can be detected there.

  • Immediately I remove the glass bowl cover and all the CO2 is released in the air thus leading a sharp drop in the CO2 level detected.
  • Later after all the CO2 is dissipated I redo tests where I slowly unseal and remove the CO2 from inside the glass bowl to see a more gradual decrease in the CO2 level.

 

Both the results have been live recorded and plotted below

Measuring in the Night of the German Summer in my balcony

 

The mini-test setup

 

The Sealed Setup to stop the air-flow in the glass bowl

 

 

The ESS Sensor CO2 Test Result

 

The highest recorded measurement goes upto 16343 ppm for CO2

 

 

Live result recording is shown here of the experiment

 

Recording with CO2 measurements numbers

 

TVOC levels in my House

 

TVOC and CO2 levels in my balcony. There is fresh air but the TVOC values are not so bad although I live close to a big street in the city.

 

Full day live data recording with TVOC. The highest TVOC level is 650 ppb and for CO2 150ppm

 

TVOC and CO2 in my Kitchen

 

In the next test; I set the Sensirion ESS in my kitchen with closed windows. And after some time I started cooking and I see that the air has more TVOC. The TVOC level reaches around 9000 ppb level. And then slowly starts to decrease as I open the kitchen window and turn off the cooking. The video is recorded for 1 hour.

 

Highest TVOC level 9000 ppb is reached but CO2 remains more or less constant

 

Conclusion

 

From the above done tests I can conclude that the Sensirion Environmental Sensor Shield (ESS) with SHTC1 humidity and temperature sensor, SGP30 VOC and CO2eq sensor are high quality sensors. They have a very fast response time and are suited to work in extreme environments. There is practically no delay in the measurement by the sensor even when a sharp change in the external environment is seen. This is important as it means that the sensor shield updates itself quickly and real-time data can be seen.

In future; I will try to update this road-test as I have ordered some sensor modules. But they will not get delivered in time for this road-test unfortunately. So I will do it later.

Thank you for appreciating my first Roadtest.

Anonymous