A gas sensor is a sensing device that detects specific gases in the air and outputs the result as electrical signals. It is widely used in household methane gas alarms and propane gas alarms, as well as in air conditioners, air purifiers, automobiles, and other applications, contributing to the safety and comfort of our daily lives.

Among them, analog output-type gas sensors offer the advantage of quick responses and real-time gas monitoring.

This article explains how to acquire data from a gas sensor (analog output type) using only an evaluation module and simple power supply unit, without using advanced equipment.

Two Methods for Acquiring Analog Output from a "Gas Sensor"

There are two main methods for acquiring analog output from a gas sensor:

① Preparing a 5VDC power supply and simple wiring components yourself
② Using an evaluation chamber (EC01)

In this article, we will explain method ①: how to acquire analog output from a gas sensor by preparing a 5VDC power supply and simple wiring components by yourself.

How to Prepare a 5VDC Power Supply and Simple Wiring Components by Yourself

This section explains the necessary equipment and the procedure for acquiring data from the gas sensor.

Required Equipment

The following items are necessary to acquire data from the gas sensor:

<Examples of USB Type-C Conversion Boards>
- Sunhayato USB Type-C Connector Conversion Board (CK-45)
- Switch Science Adafruit USB Type-C Pitch Conversion Board (Vertical Type)
- Kyohritsu Electronic Industry USB Type-C Connector DIP Conversion Kit for Power Supply, etc.

Mounting and Wiring the Gas Sensor

In this section, we will use FIGARO gas sensor "TGS2600" (gas sensor for detecting air contamination).

First, mount the gas sensor onto the evaluation module (EM26). Make sure the protruding part of the sensor is oriented toward the connector side, as indicated by the arrow in the figure above.

Next, we will use a "breadboard" and "USB Type-C power supply" to acquire output data from the gas sensor.
*For information on handling the breadboard, please refer to the instruction manual provided by the manufacturer.

Mount the evaluation module (EM26) with the gas sensor attached onto the "breadboard" as shown in the photo above.

We are using a conversion board (such as those manufactured by Sunhayato) to obtain a 5V power supply from a USB Type-C cable, along with jumper wires for easy wiring.

This time, we will use a data logger and a breadboard to easily log the output data from the gas sensor.

Connect the signal line, ground line, and +5V line to the positive (+) and negative (−) terminals of the data logger as shown in the photo above. In this setup, the positive terminals are on the upper row and the negative terminals are on the lower row.

Wiring is now complete.

Data Acquisition

Now, let's log the output of the semiconductor-type gas sensor (TGS2600) using the evaluation module (EM26) in a normal indoor environment by following the steps below.

How to Acquire Data Using the Evaluation Module (EM26)

First, turn on the data logger, set the sampling conditions (As shown in the figure above: 1-second interval, 0 to +5V range, and select channels 1 to 4 for display), and start logging in advance.

Next, plug in the USB Type-C power supply to begin supplying power.

The analog output from the gas sensor will be recorded in the data logger. To stop logging, press the "STOP" button.

Saving Analog Output Data

CSV data opened in Microsoft Excel

Once you have confirmed that the analog output data has been recorded in the data logger, save the data to your PC in CSV format. When you open the CSV data in Microsoft Excel, it will appear as shown in the figure above.

Let's try graphing the data opened in Microsoft Excel.

In the graph, the blue line shows the voltage output from the semiconductor-type gas sensor (TGS2600), while the red dashed line indicates the voltage of the +5V line. From the graph, you can see that the output from the TGS2600 in clean air undergoes a significant initial change immediately after the power is turned on.

Let's Make Use of Gas Sensors

Gas sensors are used in a wide range of fields, including safety management, health control, and environmental monitoring.

Since measurement methods and precautions vary depending on the type of gas sensor, be sure to select a sensor suitable for your application and perform measurements using the appropriate procedures.

In addition to developing and manufacturing gas sensors, FIGARO Engineering also conducts performance evaluations and characterization tests of gas sensors using high-precision inspection equipment.

On our company website, you can find easy-to-understand animations explaining how to measure gas sensor sensitivity and what precautions to take.

Learn About Gas Sensors Through Videos »