When is a motor starter required

But this is not end of our story. Starters as the name suggest are not used to start the motors specially when the motors are self starting e. They are primarily used to reduce voltage or current at the starting, thereby protecting the. We know that as load increases on the motor current drawn.

Back emf create critical role in governing the operation of dc motor.

Back emf is generated as the motor armature start to rotate in presence of magnetic field and It is counter to the supply voltage.

The back emf at the starting is zero and develops as the motor gradually speed up.

The National Electrical Manufacturers Association (NEMA) and International Electro-Technical Commission (IEC), two . Manual Starter Manual Starters, like the one pictured above have key switching elements that require manual operation. Notice the green switch on the Manual Starter above. The other main type of starter is the AC magnetic motor starter. These starters are commonly used and often, the term Motor . Full-voltage, non-reversing starters. The vast majority of motor applications require this type of starter.

It delivers fast starting of the motor , and because of its circuit simplicity, it is one of the most reliable . Sizing an IEC starter of the same type . Thus, a starter is needed in order to limit the starting current. Specifying engineers have several types of motor starters to choose from, ranging from sophisticated to bare-bones units. After the motor has started at reduced . How does the engineer decide which to choose?

There are many factors involve and different types of units are available depending on the requirements of the application. Branch-circuit short-circuit protective device. Safety switches can also be employed in the low-voltage circuit that controls the power to the AC motor starter.

Motor overload protective devices. A direct on line starter can be used if the high inrush current of the motor does not cause excessive voltage drop in the supply circuit. For example, a utility may require rural . It can be used for: - current . What Does the Application Require ? Not every motor -control application requires expensive drives or electronic controllers.

Article 4provides the requirements for electric motors while Art.