Distributor: Description and Operation

Hall Effect Distributor:

PURPOSE

The distributor houses the distributor pick-up assembly, and distributes high voltage secondary output through the rotor and distributor cap and spark plug wires to the spark plugs.


OPERATION

The distributor pick-up is a Hall Effect device. The pick-up supplies engine position and rpm information to the engine controller.

A shutter (sometimes referred to as an interrupter) is attached to the distributor shaft. The shutter contains one blade per engine cylinder. A switch plate is mounted to the distributor housing above the shutter. The switch plate contains the distributor pick-up (a Hall Effect device and magnet) through which the shutter blades rotate. As the shutter blades pass through the pick-up, they interrupt the magnetic field. The Hall effect device in the pick-up senses the change in the magnetic field and switches on and off (which creates pulses). This generates the input signal to the engine controller. The engine controller calculates engine speed through the number of pulses generated.