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EDENVIS
HIGH LEVEL EDUCATION IN ENVIRONMENTAL SCIENCES
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Real Time Air Pollution Monitoring Simulators (block diagram)
Characteristics of SnO2 Semiconductor Sensors
Items TGS 822 TGS 831
Target gas Alcohol Freons R21, R22
Typical detection range 50 - 5000 ppm 100 - 3000 ppm
Conditioning period > 7 days > 7 days
  Sym. Cond. Specs. Cond. Specs.
Sensor resistance Rs Ethanol
at 300 ppm
1 - 10 kΩ R22
at 1000 ppm
1 - 10 kΩ
Sensitivity Rs/R0 Rs ( 300 ppm)
/ Rs (50 ppm)
0.4 0.1 Rs ( 1000 ppm)
/ Rs (300 ppm)
0.4 - 0.15
Load resistance RL Min 450 Ω Variable Min 450 Ω Variable
Circuit voltage VC DC only
Ps ≤ 15 mW
Max. 24 V DC only
Ps ≤ 15 mW
Max. 24 V
Heater voltage VH AC or DC 5 0.2 V AC or DC 5 0.2 V
Heater resistance RH Room temp. 38 3 Ω Room temp. 30 3 Ω
Heater power consumption PH VH = 5 V 660 mW
(typical)
VH = 5 V 835 mW
(typical)

Items TGS 842 TGS2600
Target gas Methane Carbon monoxide
Typical detection range 500 - 10000 ppm 30 - 100 ppm
Conditioning period > 7 days > 7 days
  Sym. Cond Specs. Cond Specs.
Sensor resistance Rs Methane
at 1000 ppm
3 - 15 kΩ Clean air 10 - 90 kΩ
Sensitivity Rs/R0 Rs ( 3000 ppm)
/ Rs (1000 ppm)
0.55 0.05 Rs ( 100 ppm)
/ Rs (air)
0.3 - 0.6
Load resistance RL Min 450 Ω Variable Ps ≤ 15 mW Variable
Circuit voltage VC DC only
Ps ≤ 15 mW
Max. 24 V Ps ≤ 15 mW 5.00.2 V DC
Heater voltage VH AC or DC 5 0.2 V AC or DC 5.00.2 V DC
Heater resistance RH Room temp. 30 3 Ω Room temp. 83 Ω
Heater power consumption PH VH = 5 V 835 mW
(typical)
VH = 5 V 210 mW
 
Signal conditioning circuit
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