Characteristic curve and setpoint values
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The knock sensor shows linear characteristics in the frequency range up to around 20 kHz. The resonance frequency of the sensor itself lies at a significantly higher frequency (greater than 30 kHz). The knocking noises that usually occur in the engine have frequencies of around 7 kHz.
| Index | Explanation |
|---|---|
| 1 | Voltage |
| 2 | Signal without knocking |
| 3 | Signal with knocking |
| 4 | Frequency |
Observe the following setpoint values for the crankshaft sensor:
| Size | Value |
|---|---|
| Voltage range | 4.5 to 5.5 volts |
| Frequency range | 7 to 25 kHz |
| Maximum output current | 20 mA |
| Ambient temperature | -40 °C to 140 °C |