Crank Cam Speed Sensors

Crank, Cam Speed Sensors, Hall or Mag types, Including Distributor styles

Product Details

These sensors are used for measuring rotational position and speeds, they are most

commonly used to measure crankshafts, camshafts, and wheel speeds. The sensors

come in two main varieties, Magnetic and hall, they can be distinguished from one another

by the number of wires connecting to them, with 2 pin sensors being magnetic, and 3 pin

sensors being hall.

Hall Sensors.

Hall Sensors contain a semiconductor Hall effect IC and a magnet. The IC detects changes

in the field strength as the vane passes through the sensor gap or a tooth passes the sensor tip.

The output voltage changes from low to high when the leading edge of the tooth passes the

centre of the sensor. The vane or tooth material must be magnetically soft (such as mild steel),

do not use stainless steel. There are styles of hall sensor available that can be used with a tooth (gear)

style chopper wheel for crank angle or wheel speed sensor, or types that use a vaned rotor

passing through a hall sensor gap (51121).

Magnetic sensors.

Magnetic sensors must use shielded wire to help eliminate unwanted electrical noise.

The magnetic sensor generates a voltage between the coil wires when the magnetic

field strength changes as the tooth passes by the sensors. The sensormay be wired for 

either a Rising or Falling waveform by reversing the wires. The output voltage amplitude increases

with increased RPM. The output voltage amplitude also depends on the gap between the

sensor and the tooth. The tooth material must be magnetically soft (such as mild steel),

do not use stainless steel. May have a large number of teeth due to the sensor’s small magnetic

pole size, and are often used as crank or wheel speed sensors. The ECU needs to know

whether the wave form is rising or falling must be mounted rigidly as any vibration can

cause false signals. Refer to drawing number T02 for more details.

Ignition Combiner.

The MoTeC ignition combiner takes the ignition output from your ECU, and splits its output into

two, one output for your ignition system, and another to drive your tachometer. This frees up an

Aux output on your ECU, useful for applicationswhere they are limited.