tgs822, Ham- CB Radio, Karty katalogowe
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FIGARO
PRODUCT INFORMATION
TGS 822 -
for the detection of Organic Solvent Vapors
Features:
Applications:
* High sensitivity to organic solvent vapors
such as ethanol
* High stability and reliability over a long
period
* Long life and low cost
* Uses simple electrical circuit
* Breath alcohol detectors
* Gas leak detectors/alarms
* Solvent detectors for factories, dry clean-
ers, and semiconductor industries
The sensing element of Figaro gas sensors is a tin dioxide (SnO
2
) 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 822
has high sensitivity to the vapors of organic solvents as well as
other volatile vapors. It also has sensitivity to a variety of combustible gases
such as carbon monoxide, making it a good general purpose sensor. Also
available with a ceramic base which is highly resistant to severe environments
as high as 200
°
C (model# TGS 823).
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 in 300ppm ethanol
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 300ppm of ethanol
at various temperatures/humidities
Ro = Sensor resistance at 300ppm of ethanol
at 20
°
C and 65% R.H.
Sensitivity Characteristics
:
Temperature/Humidity Dependency
:
10
Air
5
10
Methane
2
1
R.H.
35%
50%
65%
100%
1
Carbon-
monoxide
Isobutane
0.5
0.1
Acetone
n-Hexane
Benzene
Ethanol
0.1
50
100
500
1000
5000
-20
-10
0
10
20
30
40
50
Concentration (ppm)
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.
Structure and Dimensions:
9.5
1
Sensing Element:
SnO
2
is sintered to form a thick film on
the surface of an alumina ceramic tube
which contains an internal heater.
6
1
5
2
2
Cap:
4
3
Nylon 66
3
Sensor Base:
Nylon 66
4
Flame Arrestor:
100 mesh SUS 316 double gauze
17
±
0.5
um : mm
Pin Connection and Basic Measuring Circuit:
The numbers shown around the sensor symbol in the circuit diagram at the
right correspond with the pin numbers shown in the sensor's structure drawing
(above). When the sensor is connected as shown in the basic circuit, output
across the Load Resistor (V
RL
) increases as the sensor's resistance (Rs) de-
creases, depending on gas concentration.
Basic Measuring Circuit:
Standard Circuit Conditions:
Item
Symbol
Rated Values
Remarks
Heater Voltage
VH
5.0±0.2V
AC or DC
Circuit Voltage
VC
Max. 24V
AC or DC
*PS 15mW
Load Resistance
R
L
Variable
*PS 15mW
Electrical Characteristics:
Item
Symbol
Condition
Specification
Sensor Resistance
Rs
Ethanol at 300ppm/Air
1k ~ 10k
Change Ratio of
Sensor Resistance
Rs/Ro
Rs (Ethanol at 300ppm/Air)
Rs (Ethanol at 50ppm/Air)
0.40 ± 0.1
Heater Resistance
R
H
Room temperature
38.0 ± 3.0
Heater Power
Consumption
P
H
VH=5.0V
660mW ± 55mW
Standard Test Conditions:
TGS 822 complies with the above electrical characteristics
when the sensor is tested in standard conditions as speci-
fied below:
Test Gas Conditions: 20
°±
2
°
C, 65
±
5%R.H.
Circuit Conditions:
Sensor Resistance (Rs) is calculated by
the following formula:
Rs = (
V
C
V
RL
-1) x R
L
V
C
= 10.0
±
0.1V (AC or DC),
0.05V (AC or DC),
R
L
= 10.0k
W±
1%
Preheating period before testing: More than 7 days
FIGARO USA, INC.
3703 West Lake Ave. Suite 203
Glenview, Illinois 60025
Phone: (847)-832-1701
Fax: (847)-832-1705
email: figarousa@figarosensor.com
V
H
= 5.0
±
Power dissipation across sensor electrodes
(Ps) is calculated by the following formula:
2
V
C
x Rs
2
(Rs + R
L
)
Ps =
For information on warranty, please refer to Standard Terms and
Conditions of Sale of Figaro USA Inc.
REV: 9/99
V
H
V
C
RL
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