Understanding the brake test of dc motor: Imagine trying to find out how well a DC motor is working—how much of the electrical power it uses turns into useful mechanical work. One easy and direct way to check this in a lab is by do something called a Brake Test. Let’s break it down in … Read more
Two-Point Starter A two-point starter is used for starting DC series motors. It is a simple device that helps control the starting current to prevent damage to the motor. A Two-Point Starter is a simple device used FOR safely starting a DC series motor. When a motor starts, it can draw a large amount of … Read more
Three-Point Starter A three-point starter is commonly used to safely start DC shunt motors. Just like the two-point starter, it controls the high inrush of current when the motor is switched on. But this one comes with an added feature—overload and no-voltage protection, making it more reliable. What is a Three-Point Starter? The name “three-point” … Read more
DC Motor Starter: DC motors, especially those below 1 HP (0.746 kW), can often be directly connected to a power supply. This is possible because smaller motors have a relatively high armature resistance (Ra), which naturally limits the starting current. Some examples include: However, this direct online starting method cannot be used with larger motors … Read more
What Is Speed Regulation? Think about riding a bicycle. When you’re going downhill with no backpack, it’s super fast and smooth. But going uphill with a heavy bag? How to calculate the speed regulation of DC motors? DC motors act the same way. When there’s no load, they run fast. When there’s a heavy load, … Read more
Complete Guide to Swinburne Test DC Machine The Swinburne Test is a simple and useful method to check the performance of DC motors. It helps us know how much energy the motor uses and how efficient it is. This guide will explain everything in a very simple way. Let’s learn step by step! 1. Step-by-Step … Read more
How to Speed Control of DC Shunt Motors: While controlling the speed of a DC shunt motor may seem like a daunting task, with a little bit of guidance, it can be very simple. This tutorial will break this down step by step with simple language and relevant illustrations. 🔌 A DC Shunt Motor: A … Read more
What is DC Motor Speed Control? Every electric motor has a fixed speed written on its nameplate. This is called the rated speed. It tells us how fast the motor is supposed to run when it’s working normally. But in real life, things keep changing. When the load on the motor changes — like if … Read more
Compensating Winding When a motor or generator is working, the current inside the armature (the rotating part) keeps changing, especially when the load changes suddenly or becomes too heavy. These changes in current create something called a cross magnetizing effect, which means the magnetic field gets pushed to one side. Now imagine this — every … Read more
Armature Reaction – Definition When a motor or generator is running, there are two types of magnetic fields inside it. One magnetic field comes from the main field winding (which is supposed to be there), and the second one comes from the armature winding (the rotating part). Now, when the armature winding carries current, it … Read more
Commutation in dc machine Let’s imagine the heart of a DC generator — the armature — is always spinning. As it spins, the current in its wires keeps changing direction. That means it actually creates alternating current (AC), not direct current (DC) at first. But we call it a DC generator — why? That’s because … Read more
Types of Armature Winding When we talk about armature winding in electric machines (like motors or generators), we’re simply talking about how the wires are arranged inside the machine to carry current. These wires connect at a part called the commutator. Now, depending on how these wires are connected at the ends, armature winding is … Read more
What is a DC Generator? A DC Generator is a machine that makes electricity. But not just any electricity — it makes DC electricity, which means Direct Current. Let’s make it super easy to understand. Imagine you have a toy fan that runs on batteries. The batteries give it power in one single direction — … Read more
Introduction Single phase power system is widely used as compared to three phase system for domesticpurpose, commercial purpose and to some extent in industrial purpose. As the single phase system ismore economical and the power requirement in most of the houses, shops, offices are small, this can beeasily met by single phase motor. The single … Read more
Basic Alternator Working Principle: WHAT IS ALTERNATOR? Alternating current generators are usually called alternators. They operate on the principle ofFaraday’s laws of electromagnetic induction. This law states that whenever a conductor cuts the magneticflux an emf is induced in it. This emf causes a current to flow if the circuit is closed. Fig 1.1 shows … Read more
INTRODUCTION In the year 1821 British scientist Michael Faraday explained the conversion of electrical energyinto mechanical energy by placing a current carrying conductor in a magnetic field which resulted in therotation of the conductor due to torque produced by the mutual action of electrical current and magneticfield. Based on his principle the most primitive of … Read more
