TGS821 Datasheet, PDF (1/2 Pages) List of Unclassifed Manufacturers – SPECIAL SENSOR FOR HYDROGEN GAS

FIGARO
PRODUCT INFORMATION
TGS 821 - Special Sensor for Hydrogen Gas
Features:
Applications:
* High sensitivity and selectivity to hydrogen
gas
* Good repeatability in measurement and
excellent stability
* Uses simple electrical circuit
* Ceramic base resistant to severe
environment
* Hydrogen gas detection for:
- transformer maintenance
- batteries
- steel industry usage
- etc.
The sensing element of Figaro gas sensors is a tin dioxide (SnO2) semiconductor
which has low conductivity in clean air. In the presence of a detectable gas,
the sensor's conductivity increases depending on the gas concentration in
the air. A simple electrical circuit can convert the change in conductivity to
an output signal which corresponds to the gas concentration.
The TGS 821 has high sensitivity and selectivity to hydrogen gas. The sensor
can detect concentrations as low as 50ppm, making it ideal for a variety of
industrial applications.
The figure below represents typical sensitivity char-
acteristics, all data having been gathered at standard
test conditions (see reverse side of this sheet). The Y-axis
is indicated as sensor resistance ratio (Rs/Ro) which is
defined as follows:
Rs = Sensor resistance of displayed gases at
various concentrations
Ro = Sensor resistance at 100ppm of hydrogen
The figure below represents typical temperature and
humidity dependency characteristics. Again, the Y-axis is
indicated as sensor resistance ratio (Rs/Ro), defined as
follows:
Rs = Sensor resistance at 100ppm of hydrogen
at various temperatures/humidities
Ro = Sensor resistance at 100ppm of hydrogen
at 20°C and 65% R.H.
Sensitivity Characteristics:
100
Air
10
Methane
Ethanol
Temperature/Humidity Dependency:
3
2
1
0.1
0.01
10
Carbon monoxide
100
1000
Concentration (ppm)
Hydrogen
10000
1
0.9
0.8
0.7
0.6
0.5
-20 -10
R.H.
35%
65%
95%
0
10
20
30
40
50
Ambient Temperature (°C)
IMPORTANT NOTE: OPERATING CONDITIONS IN WHICH FIGARO SENSORS ARE USED WILL VARY WITH EACH CUSTOMER’S SPECIFIC APPLICATIONS. FIGARO STRONGLY
RECOMMENDS CONSULTING OUR TECHNICAL STAFF BEFORE DEPLOYING FIGARO SENSORS IN YOUR APPLICATION AND, IN PARTICULAR, WHEN CUSTOMER’S TARGET GASES
ARE NOT LISTED HEREIN. FIGARO CANNOT ASSUME ANY RESPONSIBILITY FOR ANY USE OF ITS SENSORS IN A PRODUCT OR APPLICATION FOR WHICH SENSOR HAS NOT BEEN
SPECIFICALLY TESTED BY FIGARO.