Digital Voltmeter – Circuit & Working

A digital voltmeter (DVM) is truly a voltage measuring unit where unknown analog DC voltage is to be measured i.e. first converted to digital form and then displayed on seven segment display. The accuracy, versatility, precision, robustness of Digital electronic devices cannot be matched with that of Analog devices as the former ones are far more … Read more

Photoelectric Cell – Types & Applications

Photoelectric cell is the device which converts light energy into electrical energy. Depending upon the different photoelectric effects employed, the photoelectric cells are of following 3 types. Photoemissive cell Photoconductive cell Photovoltaic cell Photoemissive cell This cell is based on the fact that electrons are emitted from a photo-sensitive surface by the action of light. … Read more

Digital Frequency Meter – Block Diagram & Working

Functional Block diagram of Digital Frequency Meter Working principle of Digital frequency meter 1. The unknown frequency signal is fed to the Schmitt trigger. The signal may be amplified before being applied to Schmitt trigger. 2. In a Schmitt trigger, the signal is converted into a square wave with very fast rise and fall times, then … Read more

Virtual Instrumentation | Advantages

Virtual instrumentation combines thought industrial Technologies, like the personal computer with versatile software and a large variety of measurement and control hardware. Engineers use virtual instrumentation to bring the facility of flexible software and personal computer technology to test, control, and design applications making accurate analog and digital measurements. Virtual instrumentation is a pc software … Read more

Power Quality and Related Issues

Power quality refers to maintaining the near sinusoidal waveform of power distribution bus voltages and currents at rated magnitude and frequency. Power quality describes the extent of variation of the voltage, current, harmonics, and frequency of the power system. The poor power quality effects industrial competitiveness drastically and thereby impedes our efforts to turn into … Read more

Analog to Digital Converter (ADC) | Advantages & Disadvantages

What is an analog-to-digital converter? An analog-to-digital converter (ADC) is a system that converts an analog signal to a digital signal. For example, a sound picked up by a microphone into a digital signal. The output of a microphone, the voltage at a photodiode or the signal of an accelerometer are the examples of the … Read more

Difference between Analog & Digital Instrument

The basic difference between Analog & Digital Instrument is given below. S.No. Aspects Analog Instrument Digital Instrument  1.  Information form  As the position of pointer on a dial/scale  As a number 2.   Possibility of human error  Exists Does not exist  3.   Best possible accuracy  0.25%  +0.005% or greater 4.   Resolution  one in several hundreds  one part in … Read more

Sensors | Classification & Characteristics

A sensor is basically a device that converts the physical parameter (for example, viscosity, temperature, blood pressure, light intensity, humidity, speed, etc.) into a signal(may be electrical or non-electrical quantity) which can be easily measured. For example, let us consider an electrical resistance temperature element. Here the measurand is the temperature which is being sensed … Read more

Smart Sensors – Block Diagram, Architecture & Applications

A sensor producing an electrical output, when combined with some interfacing hardware is termed to be an intelligent sensor. Intelligent sensors are also called smart sensors, which is a more acceptable term now. Sensors + Interfacing hardwares = Smart sensors This type of sensor is different from other types of sensors because it carries out … Read more