Commutators

A commutator is a device used in an electric generator for converting the alternating current produced in the generator into direct current before sending the the current into an external circuit. It can also be defined as an electrical switch that periodically reverses the current in an electric motor or electrical generator.

Functions of Commutators

• Automotive Commutator can be used to convert between direct and alternating current.
• Commutator is used in electric motors to switch currents so that it can maintain magnetic polarities required to keep the shafts of the motors turning.

Characteristics of Electrical Commutator

• It consists of a set of copper contacts, fixed around the circumference of the rotating part the rotor.
• It has a set of spring-loaded carbon brushes fixed to the stationary part of the machine.
• Each segment of the commutator is separated from the adjacent segments.

Maintenance of Commutators

• The commutators should be checked for signs of discoloration.
• Use of sandpaper on the commutator bars will make them rough and it will wear out the starter brushes.
• For a longer life of the commutator, the brush, which wear faster because of its softer material component, should be replaced before they are completely worn out because a rough brush will caused sparks will damage the commutator.