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IT Literacy   Literacy is being able to read, write, listen, speak, view and represent while thinking critically and creatively about ideas and information. Literacy enables us 10 understand ourselves and the world around us, to interact with others and to share thinking. Now days, IT Literacy programmed are initiated by the Central Govt. and State Govt. and made it compulsory to create IT skilled professionals in their recruitment policies. IT literacy is also known as computer Literacy.   Computer Literacy Computer literacy is the ability to use computers and related technology efficiently, with a range of skills covering levels from elementary use to programming and advanced problem solving. By another measure, computer literacy requires some understanding of computer programming and how computers work.   10 things we have to know to be computer literate:  

Search Engines

Using a search engine is more than more...

Electric Circuits and Field   BASIC CONCEPTS An electric circuit is a path in which electrons from a voltage or current source flow. The point where those electrons enter an electrical circuit is called the "source" of electrons. The point where the electrons leave an electrical circuit is called the "return" or "earth ground". The exit point is called the "return" because electrons always end up at the source when they complete the path of an electrical circuit. The part of an electrical circuit that is between the electrons' starting point and the point where they return to the source is called an electrical circuit's "load". The load of an electrical circuit may be as simple as those that power home appliances like refrigerators, televisions, or lamps or more complicated, such as the load on the output of a hydroelectic power generating station. At the heart more...

Electrical Machine   SINGLE PHASE TRANSFORMER

• A transformer is a static device through which electrical power from one circuit is transferred to the other circuit at the same frequency.
• It can raise or lower the voltage in a circuit with a corresponding decrease or increase in the current.

  EMF Equation of a Transformer \[{{E}_{1}}=4.44f{{\phi }_{m}}{{N}_{1}},\] where,\[{{E}_{1}}\]= RMS value of induced emf in primary winding f= frequency \[{{\phi }_{m}}\]= maximum flux in core \[{{N}_{1}}\]= number of turns in primary winding. Similarly, \[{{E}_{2}}=4.44f{{\phi }_{m}}{{N}_{2}},\] where,\[{{E}_{2}}\]= RMS value of induced emf in secondary winding \[{{N}_{2}}\]= Number of turns in secondary winding Thus,           \[\frac{{{E}_{2}}}{{{E}_{1}}}=\frac{{{N}_{2}}}{{{N}_{1}}}=\frac{{{V}_{2}}}{{{V}_{1}}}=\frac{{{I}_{1}}}{{{I}_{2}}}=K\]   Losses in Transformer

Core loss or Iron loss

• It includes both hysteresis and eddy current loss.
• The core losses are almost constant at all loads.

Copper loss

• This loss is due to the ohmic resistance of the transformer more...

Power System   BASIC POWER GENERATIONS CONCEPT Energy exists in various forms like mechanical energy, electrical energy, thermal energy and so on. One form of energy can be converted into another form by suitable arrangements. Out of these forms, electrical energy is preferred due to the following reasons.

• It can be easily transported from one form to another
• Losses in energy transportation are minimum
• It can be easily controlled and regulated to suit requirements
• It can be easily converted into other forms of energy particularly mechanical and thermal
• It can be easily sub-divided.

In all power stations, electric energy is generated from other forms of energy e.g.

• Chemical energy of fuel (thermal energy)
• Energy of falling water (hydraulic energy)
• Atomic energy (nuclear energy).

Accordingly power stations are classified as:   (A) Thermal Power Stations Those power stations which convert chemical more...

Control System   CONTROL SYSTEM It is an arrangement of different physical components in such a way that we get the desired output from the input.   Classification of Control System

• Open Loop Control System: It is a system which has no feedback & its output has no effect on control action, as shown in fig.

    For example: traffic light, tap of water etc. Advantages: These systems are simple in construction & design; economic in nature; easy from the maintenance point of view, have high stability & are convenient to use when the output is difficult to measure. Disadvantages: These systems are not accurate & reliable as the accuracy depends on the calibration of the inputs & their operation is affected due to the presence of non-linearities in the elements.

• Closed more...

Electrical Measurement and Instrumentation   The measurement methods can be analog or digital methods, deflection or null methods, active or passive methods, direct or indirect methods and absolute or secondary methods. Measurement generally involves an instruments as a physical means of determining an unknown quantity or a variable called the parameter. The instrument is a means for determining the value or magnitude of the measured. The instruments can also be divided into separate classes according to several criteria as, analog or digital instrument, deflection or null type instruments, power operated (active) or self generating (passive) instruments, contacting or non contacting instruments, mechanical or electrical instruments and  or control instruments.   CLASSIFICATION OF INSTRUMENTS   Permanent Magnet Moving Coil Instrument

• PMMC instruments are used only to measure DC quantities and not AC quantities. This is because permanent magnets are used for creating magnetic fields.
• Torque equation
more...

Utlization of Electrical Energy   In electrical engineering, utilization factor, is the ratio of the maximum load which could be drawn to the rated capacity of the system, this is closely related to the concept of Load factor The Load factor is the ratio of the load that a piece of equipment actually draws (time averaged) when it is in operation to the load it could draw (which we call full load).   ELECTRICAL DRIVE Electrical drive system is widely used in large number of industrial and domestic applications like factories, transportation systems, textile mills, fans, pumps, motors, robots etc. The main advantage of this concept is, the motion control is easily optimized with the help of drive. In very simple words, the systems which control the motion of the electrical machines, are known as electrical drives. A typical drive system is assembled with a electric more...

Basic Electronics   Electronics is considered to be a branch of Physics and Electrical engineering, Electronics is the science of controlling electrical energy electrically, in which the electrons have a fundamental role. Electronics deals with electrical circuits that involve active Electrical components such as vacuum tubes, transistors, diodes, migrated circuits, associated passive electrical components, and interconnection technologies. Commonly, electronic devices contain circuitry consisting primarily or exclusively of active semiconductors supplemented with passive elements; such a circuit is described as an electronic circuit.   Industrial Electronics Insustrial electronics is a branch of electronics that deals with power electronic devices such as thyristors, SCRs, AC/DC drives, meters, sensors, analyzers, load cells automatic test equipment, multi-meters, data recorders, relays, resistors, semiconductors, transistors, waveguides, scopes, amplifiers, radio frequency (RF) circuit boards, timers, counters, etc. It covers all of the methods And facets of: control systems, instrumentation, mechanism and more...

Communication System   MODULATION The process of impressing low-frequency information to be transmitted on to a high-frequency wave, called the carrier wave, by changing the characteristics of either its amplitude, frequency, or phase angle is called modulation. The main function of the carrier wave is to carry the audio or video signal from the transmitter to the receiver. The wave that is resulted due to superimposition of audio signal and carrier wave is called the modulated wave.   Types of Modulation   AMPLITUDE MODULATION (AM) The method of varying amplitude of a high frequency carrier wave in accordance with the information to be transmitted, keeping the frequency and phase of the carrier wave unchanged is called Amplitude Modulation. The information is considered as the modulating signal and it is superimposed on the carrier wave by applying both of more...

Radio Communication and Radar   Systems   ROBOTIC RADIO COMMUNICATIONS SYSTEMS The System "Wireless Technology or Radio Based Robot Communication System" is developed for the purpose of achieving tasks that are almost impossible for the humans and for using them in hazard prone areas. The system consists of a master robot slave robot, voice module and the communication takes place with the help of a voice module. The signal is transmitted and received by the zigbee networks installed on every wireless module. The commands are given only to the master robot using the voice module and this is transmitted to the master robot via zigbee. The master robot performs the actions commanded to it, transfers the same commands to the slave robot(s) and hence performs the same actions as the master robot does. Here the zigbee in voice module acts as a transmitter, in master robot both more...