How can CEMF be best described?

CEMF, or Counter Electromotive Force, is a phenomenon that occurs in electrical circuits, particularly in motors and generators. It is generated by the motion of conductive materials within magnetic fields, which induces an opposing voltage. This opposing nature is key to understanding how electrical machines operate.

When a motor runs, the rotation of the armature within the magnetic field generates a voltage that acts in the opposite direction to the current supplied from the power source. This generated voltage opposes the applied voltage, effectively reducing the net voltage available to drive the current through the motor. This is particularly significant in the context of preventing the motor from drawing excessive amounts of current as it accelerates or reaches its operational speed.

This opposing action facilitates the effective regulation of the motor's speed and helps maintain safe operational conditions, which is why the concept of CEMF is crucial in both installation and maintenance of elevator systems and other equipment involving electric motors. Understanding that CEMF opposes applied voltage underscores its role in maintaining the performance and safety of electrical systems.