ELECTRO-MECHANICAL RELAYS
This section will cover the use of relays that are sometimes needed to control special device loads such as Generators, Air Conditioners and other high demand equipment. The content is explained through industrial controls but the principles can be easily adapted to residential wiring applications as well.
Introduction:
A relay contactor is a large relay, usually used to switch current to an electric motor or other high-power load. Large electric motors can be protected from overcurrent damage through the use of overload heaters and overload contacts. If the series-connected heaters get too hot from excessive current, the normally-closed overload contact will open, de-energizing the contactor sending power to the motor.
This and more is covered in in five parts as listed below:
