# DC Motor

A DC motor is an electrical machine which converts electrical energy into mechanical energy. The working of DC motor is based on the principle that when a current carrying conductor is placed in a magnetic field, it experiences a mechanical force. Learn everything related to DC Motor from this page.

### Working Principle of DC Motor

A DC motor is an electrical machine that converts electrical energy into mechanical energy.  The working of DC motor is based on the principle that when a current carrying conductor

### Why Electric Motors are Rated in kW and not in kVA?

Unlike Generators and Transformers, Electric Motors are rated in kW instead of kVA. We have already discussed why electric transformers are rated in kVA. This article explains why electric motors

### Voltage and Power Equations of DC Motor | Condition of Maximum Power

In this post, we will look at the voltage and power equation of a dc motor and the condition for maximum power in a dc motor. Voltage Equation of a

### Testing of DC Machines (DC Motor and DC Generator)

There are several tests that are conducted for testing a dc machine (generator or motor) to judge its performance. The most important performance tests to be conducted on the dc

### Swinburne’s Test of DC Machine (Generator and Motor)

Swinburne’s test is the simplest indirect method of testing dc machines. In this method, the dc machine (generator or motor) is run as a motor at no-load and losses of

### Split Phase Induction Motor – Operation and Characteristics

Before going to the operation and characteristics of split-phase induction motor we should first understand why single phase induction motor is not self-starting. To make a single-phase induction motor self-starting,

### Speed Control of DC Shunt Motors

The different methods of speed control in DC shunt motors are explained below, Flux Control Method Armature Control Method Voltage Control Method Multiple Voltage Control Ward Leonard System Related Topic

### Speed Control Of DC Series Motors

Although a far greater percentage of electric motors in service are ac motors, the dc motor is of considerable industrial importance. The principal advantage of a dc motor is that its speed

### Speed Control of DC Motor (Shunt, Series and Compound)

Speed control of dc motor is achieved using different methods. There are three types of dc motors. For each of them, there are different methods of speed control.  Each of

### Slip Rings and Their Connection to Modern Engineering

Slip rings are small devices that have a very important role in all types of devices, equipment, and machinery that come in all sizes, from the smallest to the largest

### Single Phase Induction Motor – Working Principle and Construction

Single-phase motors are the most familiar of all-electric motors because they are extensively used in home appliances, shops, offices etc. It is true that single-phase motors are a less efficient

### Need of a Starter (3 & 4 Point) in DC Motors

We use 3 and 4 point starters in DC motors. What happens if a DC motor is started without a starter? Let’s check it. Consider a dc motor at standstill. When

### Losses in DC Machine ( DC Generator and Motor )

The losses in a dc machine (generator or motor) may be divided into three classes viz  Copper losses  Iron or core losses and Mechanical losses.  All these losses appear as heat

### Insulation Resistance Test (IR Test) or Megger Test

Insulation Resistance or IR Test is carried out by maintenance engineers to ensure the healthiness of the overall insulation system of electrical equipment.  It reflects the presence or absence of

### How to Make a DC Motor at Home?

DC Motors works on the principle that they convert electrical energy (from a battery or voltage source) into mechanical energy (used to cause rotation). Are you thinking of making a

### How to Change the Direction of Rotation of a DC Motor?

There are two types of DC motors – Brushed DC motor and Brushless DC motor. The direction of rotation of these motors is controlled by different methods. Brushed DC Motor

### How Star Delta Starter Works?

Star-Delta starting is frequently referred to as “Soft-starting” a motor. But what is soft about his starting method? Why is it used? What are the advantages? What are the disadvantages? In

### Gramme Ring and Drum Wound Armature in DC Motors

A DC motor can be made using different types of armatures based on its application. There are 2 types of armatures. Gramme Ring Armature Drum Wound Armature Gramme Ring Armature

### EMF Equation of DC Generator: Derivation with Examples

A DC generator is a machine which converts mechanical energy (or power) into electrical energy (or power). The energy conversion is based on the principle of the production of dynamically

### Electrical and Mechanical Noise in Motors

Two types of noises occur in an electric motor, one is electrical noise and the other is mechanical noise. The causes of remedial treatments for both are discussed in this

### Electric Motor Maintenance : Preventive, Predictive and Reactive Maintenance

Electric Motors need maintenance regularly in order to avoid failure and prolong their lifespan. Generally, motors and motor parts should be maintained and tested at least every 6 months.  Then

### Construction of DC Machine (Generator & Motor)

The dc generators and dc motors have the same general construction. In fact, when the machine is being assembled, the workmen usually do not know whether it is a dc

### Compensating Windings and Interpoles in DC Machines

Compensating Windings and Interpoles are one of the important step taken to minimize the undesirable effect of armature reaction in dc machines. Armature reaction causes many undesirable effects on a

### Characteristics of DC Series Motor

In this post, we will look into the characteristics of a DC series motor. A DC series motor is one type of DC motor in which field winding is connected

### Back EMF and Its Significance in DC Motor

What is Back EMF? When the armature of a DC motor rotates under the influence of the driving torque, the armature conductors move through the magnetic field and hence emf is induced

### Armature Reaction in DC Motors

Armature reaction also occurs in a DC motor just like armature reaction in DC Generator. This is expected because when current flows through the armature conductors of a DC motor,

### Armature Reaction in DC Generator

To understand the concept of armature reaction in DC generator, please go through the previous articles describing the construction of a DC generator. The concept of armature reaction is well explained