fd2baac9

2.7.7.14. The sensor of concentration of oxygen (with heating)

The control unit to engines uses signals of the oxygen sensor for regulation of structure топли - вно - air mix, providing optimum fuel profitability and decrease in harmful emissions. Extent of enrichment or impoverishment of the fuel-air mix given to engine cylinders is determined by information on the content of oxygen in the fulfilled gases arriving from the forward oxygen sensor. Efficiency of catalytic converter of the fulfilled gases is determined by signals from the back oxygen sensor. EBU calculates efficiency of converter by comparison of a signal from the back oxygen sensor with a signal from the forward sensor.
The normal tension of a signal of the oxygen sensor constantly changes about value of 500 mV, and the frequency of a signal of the forward sensor makes not less than 5 Hz at 2500 min.-1. As a result of effect of catalytic converter the frequency of a signal of the back oxygen sensor is lower, than the frequency of a signal of the forward oxygen sensor. If the frequency of a signal of the back oxygen sensor during a wide interval of time coincides with the frequency of a signal of the forward oxygen sensor, it indicates decrease in efficiency of catalytic converter or malfunction of a power supply system of the engine.

Fig. 2.247. Sensor of concentration of oxygen




Fig. 2.248. Scheme of connections of the sensor of concentration of oxygen with EBU