Basic Electrical Engineering MCQs Part 1

Basic Electrical Engineering MCQs Part 1 No current flows between two charged bodies when they have same No current flows between two charged bodies when they have same Charge Capacity Potential None of the above Correct answer: 3. Potential Electric current is due to the flow of Electric current is due to the flow of … Read more

Induction Motor MCQs Part 7

Induction Motor MCQs Part 7 The speed of the rotating flux of a 3-phase, 4 pole induction motor having 50 Hz supply will be The speed of the rotating flux of a 3-phase, 4 pole induction motor having 50 Hz supply will be: 1500 RPM 1000 RPM 750 RPM 3000 RPM Correct answer: 1. 1500 … Read more

Induction Motor MCQs Part 6

Induction motor MCQs Part 6 The outer cage winding in the double squirrel cage induction motor has The outer cage winding in double squirrel cage induction motor has: Low resistance High resistance High inductance None of these Correct answer: 2. High resistance For a 3-phase induction motor, the mechanical power developed in terms of air … Read more

Switchgear and Protection MCQ Questions

Switchgear and Protection MCQ Questions The fuse is best defined as a The fuse is best defined as a: Current Control device Current Limiting device Protection device None of these Correct answer: 3. Protection device You might want to see: Power System Protection MCQ Questions The circuit breaker must be able to perform the function … Read more

Directional Overcurrent Protection Relay

A direction overcurrent protection relay is a type of relay that is able to discriminate between current in one direction versus current in the other direction. It is used for power system protection where alongside magnitude, the direction of line current is also important. In this article you’ll learn working of directional overcurrent protection relay. … Read more

Induction Motor MCQs part 5

Induction Motor MCQs part 5 For induction motor the relation among synchronous speed (Ns), rotor speed (N) and slip (s) is given by For induction motor the relation among synchronous speed (Ns), rotor speed (N) and slip (s) is given by: N = (s – I) Ns N = ( I +s) N N = … Read more

DC Motor Speed Control using PWM from VSD

One of the very simple method for controlling the speed and torque characteristics of a wound-field DC motor is by varying current through the field winding. In this article, you’ll learn the DC motor speed control using PWM from a variable-speed drive or VSD. The solution employs a electronic power control circuit very rapidly switch … Read more

DC Motor Speed Control by Variation of Current through the Field Winding

In this article you’ll learn DC motor speed control by varying current through field winding. A very simple method for controlling the speed and torque characteristics of a wound-field (nonpermanent magnet) DC motor is to control the amount of current through the field winding. Decreasing the field control resistor’s resistance allows more current through the … Read more

Thermocouple – Basic Construction and Working of Thermocouple

When two dissimilar metal wires are joined together at one end, a voltage is produced at the other end that is approximately proportional to temperature. That is to say, the junction of two different metals behaves like a temperature-sensitive battery. This form of electrical temperature sensor is called a thermocouple: This phenomenon provides us with … Read more

Difference between Instantaneous and Time Overcurrent Relay Protection

A protective relay is an electrical device that detects the electrical fault and initiates the operation of the circuit breaker to isolate the defective components from the power system. In this article you’ll learn the difference between Instantaneous and Time Overcurrent Relay Protection. Perhaps the most basic and necessary protective relay function is overcurrent: commanding a circuit breaker to trip … Read more