A starter lets you turn an electric motor (or motor-controlled electrical equipment) on or off, while providing overload protection. It represents another evolution in control. Now, there is a power control device that offers more than just a manual on/off control, such as a knife blade switch. The manual starter also provides a means to protect the motor from burnout: overload protection.
There are two main types of
motor starters: the manual starter and the magnetic motor starter.
Manual Starter
As the name implies, a manual starter is operated manually. Operating a manual starter is fairly simple and straightforward: you press a button or toggle (mounted directly on the starter) to start or stop the connected electrical equipment. Mechanical linkages from the buttons or toggle force the contacts to open and close, starting and stopping the motor.
The other main type of starter is the AC magnetic motor starter. These are so commonly used, that when we use the term “motor starter,” we mean “AC magnetic motor starter” unless specifically stated otherwise.
We will begin with a look into what they are and how they work, and finish up with an overview of specific types of motor starters.
Motor starters offer some additional capabilities not available in a manual starter, most importantly, remote and automatic operation. In other words, the magnetic motor starter did for manual starters what the magnetic contactor did for manual controllers: it removed the operator from the immediate area.
Like the magnetic contactor, the motor starter depends on magnets and magnetism for its operation. These additional capabilities are due, for the most part, to the motor starter’s electromagnetic operation and the control circuit.
