© 2005-2016 Nira Control AB 17
Example of an inductive CKP sensor signal when a ”2 lost” is detected from a pulse wheel
with a ”60 – 2 lost” pattern
Zero crossing detection and crank polarity
When using an inductive sensor the system uses zero crossing detection to
determine the position of the crankshaft.
Examlpe of zero crossing detection for falling & rising edge.
The picture above shows two types of zero crossing.
The red circle shows zero crossing at the transition from high level to
low level, falling edge
The blue circle shows zero crossing at the transition from low level to
high level, rising edge. In the “lost gap” the zero crossing is widely
spread and can’t be uniquely defined
By swapping the polarity of the inductive sensor the signal will be inverted.
NIRA i7x uses zero crossing detection at falling edge, which means the scope
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