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Signal shape and setpoint values

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Thanks to a residual oxygen content that equates to a mixture composition of lambda = 1, the voltage measurement on the measuring cell indicates a voltage of 450 millivolts. When lambda = 1, the composition of the exhaust gas of the different material is ideal.

Fig 1: Oxygen Sensor Catalytic Converter Graph
G09909315Courtesy of BMW OF NORTH AMERICA, INC.
Item Explanation
1 Voltage to measuring cell
2 Signal path
3 Lambda

Observe the following setpoint values for the monitoring sensor:

Variable Value
Lower voltage range of oxygen sensor heating 10.7 to 16.5 V
Voltage of oxygen sensor heating in warm-up phase 4 V
Operating temperature ≥ 350 °C
Heating resistance at 20 °C 9 Ω ±2 Ω
Maximum pump current 2.2 to 2.6 Ω