AGSM user manual
The Allsensing Gas Sensor Module provides an easy way to add gas detectors to the Internet of Things.
Description
The Allsensing Gas Sensor Module (AGSM) provides an easy way to add gas detectors to the Internet of Things. Here are some key features and specifications:
Gas Calibration: Once the gas calibration is complete, the AGSM sends sensor concentration values (in ppb) using UART communication.
Response Time: It is not suitable for environments that require a fast response time (T90<30Sec). It is designed for long-term environmental change monitoring.
Sensor Stabilization Time: A minimum of 30 minutes to 1 hour of sensor stabilization time is required. Temperature Compensation & Gas Sensor Calibration Algorithm: The module applies a temperature compensation and gas sensor calibration algorithm.
Sensor Signal Value: The sensor signal value (raw data) output from the sensor driving circuit can be checked (23bit adc). Compatibility: The AGSM product can be applied in conjunction with Arduino and compatible products.
Integration: It can be easily integrated and applied to small, lightweight, high-performance, low-power wireless gas detectors, portable and network solutions.
Gas Sensors: The AGSM is supplied in a form applied with individual gas sensors for CO, H2S, SO2, NO2, O3.
Sensor Calibration:
If the user has calibration gas and a test environment, Zero calibration and Span Calibration can be performed using communication commands.
It is recommended to calibrate the gas sensor (Span Calibration) every six months.
The AGSM product was calibrated using a small chamber of 400mL.

Specifications and Connection Methods
Module Specifications
Measured Gases
CO, H2S, SO2, NO2, O3 (individual measurements)
Operating Principle
Solid electrolyte electrochemical (3 electrodes)
Measurement Range
### Sensor Specifications
Accuracy
<5% @ Full Range
Communication Output
UART (TTL 3.3V, 5.0V)
Expected Operating Life
> 5 years (10 years @ 25± 10C; 60 ± 30% RH)
Electrical Characteristics
Operating Voltage
DC 3.3V ~ 5.0V
Operating Current
Max 13mA (3.3VDC)
Power Consumption
≤43mW
Environment
Operating Temperature
-20 to 40 °C
Operating Humidity
15 to 95% (Based on Standard Conditions: 25 ºC, 50% RH and 1 atm)
Sensor Specifications
Carbon Monoxide (CO)
0~100ppm
0.1ppm
5% of Full range
<30 sec
Hydrogen Sulfide (H2S)
0~10ppm
10ppb
5% of Full range
<30 sec
Sulfur Dioxide (SO2)
0~20ppm
50ppb
5% of Full range
<30 sec
Nitrogen Dioxide (NO2)
0~5ppm
20ppb
5% of Full range
<30 min
Ozone (O3)
0~5ppm
20ppb
5% of Full range
<30 sec
Pin Connection
Connector(default): Molex 53261, Yeonho 12505WR
Pin header(option): 2.54 pitch(V:VCC, G:GND, R: Rxd, T: TxD)

Dimension
Size: L X W (33 x 21 mm)

Communication protocols
Defaults
+ Voltage level: DC 3.3 V or 5.0V
+ Baud: 9600
+ Data bits: 8
+ Stop bits: 1
+ Parity: None
+ Flow Control: None
Commands
<CR>,
Single data output. Output: SN [XXXXXXXXXXXX], PPB [0 : 999999], TEMP [-99 : 99], RH [0 : 99], ADC[ADCCount], TempDigital, RHDigital
C<cr>, c<cr>
Continuous data output. Resets upon reboot and does not store status level in internal memory.
Z
Zero user calibration. Recalculates and calibrates the sensor value to output 0ppm.
B
Barcode entry. Inputs the barcode information recorded on the sensor.
S
Span user calibration. Recalculates and calibrates the sensor's measurement sensitivity by injecting calibration gas (based on PPM).
e
Internal memory readout. Checks the configuration information values stored inside the module.
D<cr>
LED ON/OFF. Status information is not stored in internal memory.
r<cr>
System reset.
Command Examples
\r
081821011255, 212, 23, 18, 2194921, 23490, 18665
c\r
081821011255, 212, 23, 18, 2194921, 23490, 18665
S
Enter span gas value in PPM:
Setting span...
done
Z
Setting zero...
done
B
Remove Sensor and Scan:
Setting OC...done
e
Serial Number= 112020010530
Barcode= 081821011255 110507 NO2 2108 -28.57
ADC Zero= 2165186
ADC_SpanCalValue= 1890818
Temperature Zero(x1000)= 24366
Humidity Zero(x1000)= 16797
Temperature Span(x1000)= 24205
Humidity Span(x1000)= 17139
Calibration GAS(x100)(ppm)= 250
Calibration InA(x100)= -2857
Max Range(ppm)= 5
NoneSensorADC Zero= 2165186
Firmware Version= 2022-03-23B-04”
r\r
reset
D\r
LED OFF
LED ON
Precautions
Please use within the specified standards and be careful with connections.
Use in the vicinity of excessive chemicals may damage the sensor.
Prolonged exposure to high temperatures and humidity may cause the sensor to malfunction.
Impacts above a certain threshold may cause temporary malfunctions.
Failure to follow these instructions may result in product damage.
It is recommended to use as a safety device or supplementary device for safety reasons.
Manufacturer / Contact (A/S)
Manufacturer: ㈜ 올센싱 https://www.allsensing.com/
Address: A2214, 184, Jungbu-daero, Giheung-gu, Yongin-si, Gyeonggi-do, Republic of Korea
Contact: E-MAIL: [email protected]
I hope this information is helpful! If you have any other questions, feel free to ask.
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