PRODUCT INFORMATION
Applications:
Features:
TGS 832-A00 - for the detection of Chlorouorocarbons
The gure below represents typical sensitivity characteristics,
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 dened as follows:
Rs = Sensor resistance of displayed gases at
various concentrations
Ro = Sensor resistance at 100ppm of R-134a
The gure below represents typical temperature and humidity
dependency characteristics. Again, the Y-axis is indicated as
sensor resistance ratio (Rs/Ro), dened as follows:
Rs = Sensor resistance at 100ppm of R-134a
at various temperatures/humidities
Ro = Sensor resistance at 100ppm of R-134a
at 20°C and 65% R.H.
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 832-A00 has high sensitivity to refrigerant gases commonly used in air
conditioning systems and refrigerators such as R-134a, R-404a, R-407c, and R-410.
TGS832-A00 has a gas diffusion hole in the sensor cap as well as in the sensor
base. By using the sensor with a suction pump, response speed can be accelerated,
making it suitable for portable gas leakage checkers.
* Portable and xed installation refrigerant
leak detectors
* High sensitivity to refrigerant gases
* Quick response
* Long term stability
* Uses simple electrical circuit
Temperature/Humidity Dependency:
Sensitivity Characteristics:
0.1
1
10
10 100 1000
Air
R-407c
Ethanol
R-134a
R-410a
R-404a
R-22
Rs/Ro
Concentration (ppm)
-10 0 10 20 30 40 50 60
Rs/Ro
Ambient Temperature (°C)
2.0
0.5
40% R.H.
65% R.H.
100% R.H.
1.2
1.0
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.
Item Symbol Condition Specication
Sensor resistance Rs R-134a at 100ppm/air 4kΩ ~ 40kΩ
Change ratio of
sensor resistance Rs/Ro Rs (R-134a at 300ppm/air)
Rs (R-134a at 100ppm/air) 0.50 ~ 0.65
Heater resistance RHRoom temperature 30.0 ± 3.0Ω
Heater power consumption PHVH=5.0V 835mW (typical)
Structure and Dimensions:
1 Sensing Element:
SnO2 is sintered to form a thick lm on
the surface of an alumina ceramic tube
which contains an internal heater.
2 Sensor Cap
3 Sensor Base:
Nylon 66
4 Flame Arrestor:
100 mesh SUS316 double gauze
Standard Circuit Conditions:
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 (VRL) increases as the sensor's resistance (Rs) decreases, depending on
gas concentration.
Sensor Resistance (Rs) is calculated by
the following formula:
Power dissipation across sensor electrodes (Ps)
is calculated by the following formula:
Standard Test Conditions:
TGS 832 complies with the above electrical characteristics
when the sensor is tested in standard conditions as specied
below:
Test Gas Conditions: 20°±2°C, 65±5%R.H.
Circuit Conditions: VC = 10.0±0.1V (AC or DC),
VH = 5.0±0.05V (AC or DC),
RL = 10.0kΩ±1%
Preheating period before testing: More than 7 days
Electrical Characteristics:
Basic Measuring Circuit:
REV: 10/12
Rs = ( -1) x RL
VC
VRL
Ps = VC2 x Rs
(Rs + RL)2
Item Symbol Rated Value Remarks
Heater voltage VH5.0±0.2V AC or DC
Circuit volatge VCmax. 24V DC only
Ps≤15mW
Load Resistance RLvariable 0.45kΩ min.
17 ± 0.5
9.5
16.5±0.5
6.5±0.5
1.0±0.5
6
3
4
2
5
1
45˚
45˚
um : mm
FIGARO ENGINEERING INC.
1-5-11 Senba-nishi
Mino, Osaka 562-8505 JAPAN
Phone: (81)-72-728-2561
Fax: (81)-72-728-0467
www.garo.co.jp
email: garo@garo.co.jp