Riken Keiki GD-A80 Series, Руководство по эксплуатации

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9 Product Specifications 9-2. Detection principle
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9-2. Detection principle
<Catalytic Combustion>
When a combustible gas burns on the surface of an oxidation catalyst, the catalytic combustion type sensor
considers resultant combustion heat as temperature and resistance changes in the platinum wire coil, and
measures their gas concentrations.
This sensor detects any combustible gases. The detection range is from zero to the lower explosive limit.
When a highly-concentrated gas over the lower explosive limit comes into contact with the sensor, it may
cause a break.
0.8 - 1.0 mm
Basic Circuit
0.5 - 0.7 mm
Structure Diagram
Oxidation catalyst
Alumina
Variable resistor for bridge
voltage adjustment
Platinum wire coil
Power supply
Fixed
resistance
Variable resistor for bridge
equilibrium adjustment
D: Detecting element
C: Compensating
element
Fixed
resistance
Switch