Why is a starter required for a DC motor?

Answer 1

Large DC motors with field windings instead of permanent magnets present a very heavy load when starting. To prevent fuses blowing, a series of ever smaller resistors are sequentially switched in series with the motor. As the motor picks up speed, a back EMF in opposition to the applied voltage limits the maximum current. When the motor reaches it's running speed the 'starter' is out of circuit.

Answer 2

When a DC motor is initially energized, there is no back emf because the rotor is not turning. That means that the motor will draw very high current. If the motor is larger, the high current can damage the commutator, the windings or the power supply equipment. Therefore, a starter is needed to insert a current limiting resistor or sequence of resistors until the motor gets up to speed.

Answer 3

Usually if you have full field the armature rpm is dependent on the armature voltage. If the power source can supply current enough for full load torque or stall torque, the motor endeavors to take all the power it needs to be at full speed. In short, if there is inertia in the load, you may break the motor's output drive couplings and gears if you don't limit the starting current by using a resistor.

Answer 4

starters are used in dc motor to minimize the high starting current and also protect the motor.

Answer 5

to over come the back emf

Answer 6

To reduce the high starting current