Power Systems Operation and Control Interview questions
What is load curve? The curve drawn between the variations of load on the power station with reference to time is known as load curve. There are three types, Daily…
How Integral Controller Reduces offset error ?
First we have to know how offset error appears in Proportional controller. Click here to read the article on proportional controller offset error. Automatic reset or integral action corrects for…
Why Offset in Proportional Controller ?
Proportional controller: With proportional band, the controller output changes in "proportion" to the error between process variable and set point. The amplitude of the change is adjustable from 1% to…
Basics of Fire Extinguisher
Fire Extinguishers are more popular, compared to the remaining Fire Protection Systems. You may identify them as red colour cylinders, seen generally at the doors. Fire Extinguishers come of a…
Thermistors and Resistance Temperature Detectors (RTDs)
One of the simplest classes of temperature sensor is one where temperature effects a change in electrical resistance. With this type of primary sensing element, a simple ohmmeter is able…
What is a Network ?
What is a Network ? A network consists of two or more computers that are linked in order to share resources (such as Internet, Data, printers and CD-ROMs), exchange files,…
Control Valve Positioner Working Principle
A Control Valve Positioner is a device used to increase or decrease the air load pressure driving the actuator until the valve's stem reaches a “POSITION” balanced to the output SIGNAL from…
Bubble Tube Level Measurement Principle
In the bubble type level system, liquid level is determined by measuring the pressure required to force a gas into a liquid at a point beneath the surface. This method…
How to test SCR using Multimeter
This post will discuss about testing SCR - Silicon Controlled Rectifier with thte help of Ohmmeter. The thyristor pin assignment diagram of TO-220 package is given for ready reference. Identify the…
Difference between Permanent Magnet BLDC and DC Motor
What are the main Difference between Permanent Magnet BLDC and DC Motor ?
