Vehicle Speed Sensor (VSS)
Brand information
SCHNECKE
- Provider of Vehicle Speed Sensor to the worldwide OEM market and aftermarket.
- SCHNECKE offers complete Vehicle Speed Sensor coverage for Asian, Domestic and European vehicles,
- Top brand awareness and unsurpassed quality.
Vehicle speed sensors are usually either inductive or optical sensors. The most common inductive sensors consist of a rod magnet on top of a magnetic pin that is surrounded by a fixed coil. This sensor is mounted a fixed distance from a ferromagnetic rotor with teeth. As the rotor turns and a tooth comes into the proximity of the rod, the magnetic flux in the coil changes. This change in flux results in a voltage pulse across the coil. The vehicles engine control module counts these voltage pulses and computes the vehicles speed. Optical sensors also generate pulses at a frequency corresponding to the rotor rotation, but instead of measuring magnetic flux, the optical sensor measures either reflected light or light allowed to pass through slits. When using an optical sensor the rotor either has light and dark marks for the optical sensor to detect the reflected light using photosensors, or a series of slits that allows light from an infrared source to pass through and be detected by a phototransistor on the other side.