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The principle of operation of a catalytic converter (catalyst)
Gasoline Model MAZDA 323 can be equipped with regulated or unregulated catalyst. Adjustable catalyst requires regulated smeseobrazovatelya. Under controlled smeseobrazovatelem understood carburetor or fuel injection system, in which the fuel to air ratio can be continuously varied depending on the mode of operation and the oxygen content in the exhaust gases. With the same carburetor that is not possible, because it does not have a corresponding control unit. Therefore, use or electronically controlled carburetor or fuel injection system. Control signals received from smeseobrazovatel lambda probe which is located in front of the system and blown by the flow of exhaust gases. Lambda probe - an electrical sensor, which indicates the residual oxygen content in the exhaust gases in the form of electric oscillations and suggests air-fuel mixture. In fractions of a second lambda probe may file a corresponding signal to the control smeseobrazovatelya, so it can be kept optimum ratio of fuel and air. On the one hand it is necessary, as always changing modes (idling, the throttle), on the other hand, because the post-combustion in the catalyst can occur only if there is sufficient exhaust gas of the gasoline. Thus. to the catalyst at a temperature of + 300 ?� - + 800 ?� C generally afterburning could occur it is necessary that the fuel-air mixture has more fuel than pure combustion. Widely used trifunctional catalyst. This means that when such a catalyst based on lambda adjustment is performed simultaneously the oxidation of carbon monoxide (CO) and hydrocarbons (HC) and reduction of nitrogen oxide (N0 x)
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