World Of Electrical

What is Instrumentation? And Modes of Measurement Definition of Instrumentation The technology of using instruments to measure and control the physical and chemical properties of materials is called “ instrumentation ". What is Instrumentation? And Modes of Measurement When the instruments are used for the measurement and control of industrial manufacturing , conversion or treatment processes, the term process instrumentation is applied. When the measuring and controlling instruments are combined so that measurements provide impulses for remote automatic action, the result is called a control system. Modes of Measurement There are the three modes of measurement: 1. Primary Measurement 2. Secondary Measurement 3. Tertiary Measurement All the three modes are described below: (1) Primary Measurements In the primary measurement sought value of a parameter is determined by comparing it directly with reference standar...

Variable Inductance Transducer | Classification Of Variable Inductance Transducer Variable Inductance Transducer | Classification Of Variable Inductance Transducer These are based on a change in the magnetic characteristic of an electrical circuit in response to a measurand which may be displacement, velocity, acceleration etc. Variable inductive transducer may be classified as follows: 1.Self-generating type In this type voltage is generated because of the relative motion between a conductor and a magnetic field. These may be further classified as follows: (A)Electromagnetic type (B)Electrodynamic type (C)Eddy current type 2.Passive type In this type the motion of an object results in change in the inductance of the coils of the transducer. These may be further classified as follows: (A)Variable reluctance (B)Mutual inductance (C)Differential transfer type 1.Self-generating Type (A)Eleotromagnetic t...

Cathode Ray Oscilloscope ( C. R. O. ) | Working and Application of C. R. O Cathode Ray Oscilloscope ( C. R. O. ) | Working and Application of C. R. O Definition and Basic Details of C. R. O. A cathode-ray oscilloscope is an instrument which presents signal wave-forms visually. It is also useful for comparing two signals in phase,frequency or amplitude. A  C.R.O.can operate upto 50 MHz, can allow viewing of signals within a time span of a few nanoseconds and can provide a number of waveform displays simultaneously on the screen. It also has the ability to hold the displays for a short or long time (of many hours)so that original signal may be compared with one coming on later. A block diagram of cathode-ray oscilloscope is shown in below figure Block Diagram of cathode Ray Oscilloscope Cathode Ray Tube(C.R.T.) A cathode ray tube is the 'heart of an oscilloscope and is very similar to the pic...

Measurement of Resistance | Different Methods to Measure Resistance | Measurement of Resistance by MEGGAR Measurement of resistance by Different ways which all the methods are described in this article. Methods Of Measuring A Resistance The resistance may be measured by the following methods which all the methods are mentioned below: (1) Ammeter voltmeter method This method is mainly applicable to medium resistances and the accuracy is moderate or around 1%. (2) Ohmmeter This is an instrument used for directly indicating the value of the unknown resistance connected across its terminals. It provides a very quick but moderately accurate means of resistance measurement. (3) Meggar This is an instrument for measuring very high resistances such as insulation resistance of the cable. (4) Wheatstone Bridge This is the best and the commonest method of measuring medium resistances and measures resistance with a good degree of accur...

What is the Wattmeter ? | Types of Wattmeter | Electrical Measurement Theory Definition A wattmeter is a combination of an ammeter and a voltmeter and, therefore consists of two coils known as current coil and pressure coil. What is the Wattmeter ? | Types of Wattmeter | Electrical Measurement Theory The operating torque is produced due to interaction of fluxes on account of currents in current and pressure coils. There are following three types of wattmeters: 1.Dynamometer type wattmeter 2.Induction wattmeter 3.Electrostatic wattmeter. Dynamometer type Wattmeter Let consider V= supply voltage I = load current R = Resistance of the moving coil circuit. Current through fixed coils, If = I Current through the moving coil, Im = V / R Deflecting torque, Td ∝ If × Im = IV / R For a D.C.circuit the deflecting torque is thus proportional to the power. The figure of dynamometer type wattmeter is shown in below image 👇 👇 Dynamometer ...

Strain Gauge | Different Types of strain Gauge | Electrical Measurement Theory Strain Gauge | Different Types of strain Gauge | Electrical Measurement Theory There are mainly two types of strain Gauge: Semiconductor Strain Gauge Capacitive Strain Gauge These two types of strain gauges are described below in detail: Semi-conductor Strain Gauges Semi-conductor strain gauges depend for their action upon piezo- resistive effect, such that the change in value of the resistance due to change in resistivity. These gauges are used where a uery high gauge factor and small enuelope are required. For semi-conductor strain gauges semiconducting materials such as silicon and germanium are used. A typical strain gauge consists of a strain sensitive crystal material and leads that are sandwiched in a protective matrix. The production of these gauges employs conventional semi-conductor technology using semi-conducting wafers or filaments whi...

Moving Iron Instruments and Moving Coil Instruments | Electrical Measurement Theory Moving Iron Instruments Moving Iron Instruments and Moving Coil Instruments | Electrical Measurement Theory Moving-iron instruments are commonly used in laboratories and switch boards at commercial frequencies because they are very cheap and can be manufactured with required accuracy. Moving-iron instruments can be divided into two types: (1)Attraction type In this type a sheet of soft iron is attracted towards a solenoid. (2)Repulsion type In which two parallel rods or strips of soft iron, magnetised inside a solenoid are regarded as repelling each other. Moving Coil Instruments The moving-coil instruments have a following two types: (1)Permanent-magnet type It can be used for D.C.only. (2)Dynamometer type It can be used both for A.C.and D.C. PMMC - Permanent-magnet Moving-Coil Type Instruments Figure of Permanent Magnet Moving Co...

Working Of Transducer and Classification of Transducer Definition A transducer is a device which converts the energy from one form to another. Working Of Transducer and Classification of Transducer Most of the transducers either convert electrical energy into mechanical displacement or convert some non-electrical physical quantity such that force, sound, temperature etc. to an electrical signal. A transducer performs the following functions in an electronic instrumentation system: ✓Detects or senses the presence,magnitude and changes in physical quantity being measured. ✓Provides a proportional electrical output signal. Classification Of Transducer Transducers are mainly classified into two groups as shown below: (1)Active transducers They are also known as self-generating type transducers. These transducers develop their own voltage or current. The energy required for production of an output signal is obtained from the physical phenomenon ...

What are the Measuring Instruments? And Classification of Measuring Instruments Definition The instruments used for all electrical measurements are called measuring instruments.  What are the Measuring Instruments? And Classification of Measuring Instruments They include ammeters, voltmeters, wattmeters, energy meters etc. The various electrical instruments may mainly classified into two groups 1. Absolute instruments 2. Secondary instruments 1.Absolute instruments Those are the instruments which indicate the quantity to be measured in terms of the constants of the instrument and in order to find out the quantity in the practical units it is necessary to multiply such deflections with an instrument constant. No previous calibration or comparison is necessary in this case. The most common absolute instrument is tangent galvanometer which gives the measured current in terms of tangent of the deflected angle, the radius ...