Page 319 - Electronic Mechanic - TP - Volume - 2

ELECTRONICS MECHANIC - CITS

EXERCISE 215: Familiarize with different types of DC motor
and demonstrate the different parts

Objectives

At the end of this exercise you shall be able to:
• to demonstrate and study different parts of DC motor.

Note: A nameplate contains a large amount of useful information relating to the motor including the type
RPM frame size and power of the motor. By the template we can easily recognize which type motor we
are using.

Procedure

1 DC Motor: A DC motor is an electrical motor that uses direct current to produce mechanical force; the most
common types rely on magnetic forces produced by currents in the coils. Nearly all types of DC motors
have some internal mechanism, either electromechanical or electronic; to periodically change the direction of
current in part of the motor. DC motors were the first form of motors widely used, as they could be powered
from existing direct current lighting.
2 Working Principle: A DC motor is an electrical machine which converts electrical energy in to mechanical
energy. The basic working principle of the DC motor is that whenever a current carrying conductor places in
the magnetic field, it experiences a mechanical force. Its works on Fleming’s left-hand rule and its magnitude
decide the direction of this force.

Types of DC motor:

DC motor

Separately excited Self excited Permanent magnet

Shunt excited Series excited Compound excited

Cumulative compound motor

Long Shunt

Short Shunt
Differential compound motor

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