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Showing posts from April, 2018

CIRCUIT ELEMENTS

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What are the network elements ? Why we need these ?      Well, simple questions with explanatory answers !  Not exactly if you keep up the reading. As we know the ,An Electrical network is an interconnection of electrical components. So there will be a closed path  for current flow through various circuit components to produce the desired function.The electrical components can be broadly classified  to two as follows, 1. Active Components  In general terms it could be defined as the components with an ability to amplify or process the electrical signal or components having some energy levels to impart. examples are diode,transistors, scr, opamps etc. 2. Passive Components    from the concept about the active components its easy to understand whats are passive ones. ie, The components doesn't having any capability to amplify or process electrical signal its own, but these could support these processes while active components ...

Insulators

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We know electricity as the most dangerous and powerful source of energy existing in nature. So to protect humans from it's contact, we need some material. A kind of material which opposes the flow of heat, light, sound and electricity is known as an insulator. In other words, these are the material which have a high value of resistance beyond few, 100 mega Ohms. So practically no flow of current occurs through these types of materials. Stephen Gray was the one to introduce conduction of electrons to the world. he also stated the different materials have different property towards conduction. When he used the metal as conductor, on the other side used silk as an insulator because it showed high resistance towards electric conduction. Later it was David Brook who altered the old style of insulator and used it for his telegraph lines during 1864 to 1867.  His insulator had a thick metal casing around blown glass, the assembly was held together with molten sulfur. Out of the tube ex...

A Glance at protective devices

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A protective device is an equipment that can protect machinery,components and man in operation. Or in electrical aspects, a protective device can act against short circuit, over current and such abnormalities in a system.           There are many types of protective devices employed in the modern era though a major part includes the former. The main types among them are: 1) Fuses 2) Circuit breaker 3) Relays 4) Earthing devices FUSE: A fuse is a small crosection conducting path or wire and it is enclosed by a insulating non combustible cartridge. It allows only a rated value of current passing through it say the 'rated amps" And also it sacrifices it's life when an increased or abnormal current flows through it.! Principle of operation of a fuse is obviously the melting of wire when it us heated Up while caring more than rated value in prior to eqn i2rt. And there by breaks the circuit. A main drawback of a c...

Safety and Protection

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Are you excited about Electricity ? You may have to know much about the enormous behavior of  current. No, it wont bite you unless you are not cared about it.      Here we bring some safety and protection aspects in electrical power handling. As we know the current is the flow of charges, which exists if and only if  there is potential difference and a closed loop(otherwise ideally we could say infinite resistance in the path, resulting in zero current).    When we are focusing on our safety its better to consider the after effects as there is a potential and closed path, when we make some contacts.It's all that matters is the threat of electrical shock . It depends on the power level of the source, that it could circulate a certain amount of charge per second through your body. The different current levels and effects are as follows  1mA - some threshold of sensation 10mA - effect may vary from Mild sensation to painful shock ...