Electricals

                                  GENERATORS

A generator is a machine that converts kinetic energy into electricity. The generator works as the reverse of an electric motor. Generators are of two types:

1.       AC Generators

2.       DC Generators

                                                AC Generator

                AC generators produce alternating current electricity and they are of two structures. The two structures are: The slip ring AC generators and the alternators.

The common difference between the slip ring generators and the alternators is that in a slip ring AC  generator, a coil of wire moves in a magnetic field while in an alternator, a magnetic field is made to rotate in a coil of wire.

                            TRANSFORMERS

A transformer is a device that increases or decreases an AC voltage and it has no moving parts. It works on the principle of electromagnetic induction. It is made up of an iron with a soft core and two coils of wire. Transformers are used to prevent energy loss. As electricity flows in a wire heat is given off and as heat is given off energy is lost. In order not to lose energy, the voltage is increased and the current is reduced. The voltage in a wire is inversely proportional to the current and that is why wattage [power] doesn’t increase or decrease. The amount of turns of input coil in a transformer and the amount of turns of output coil shows the type of transformer shown. A step-up transformer has more turns of input coil than the output coil and reverse for a step-down transformer.

A STEP DOWN TRANSFORMER

INDUCTION COIL

          An induction coil is an instrument for producing high voltage from a low one. The first principles of the induction coil were discovered by Michael faraday. The instruments comprises of two coils. A primary coil ' a winding of a few hundred turns of thick insulated wire and a secondary coil of a winding of several thousand turns of thin insulated wire wrapped around the primary.

          A low voltage DC source provides current for the primary, and is switched rapidly on and off by means of an iron armature similar to that of an electric bell. Current passes through an adjustable screw on which the flat steel spring supporting the armature rests, and into the primary coil. This magnetizes the soft iron core of the coil, which attracts the iron armature towards it. As the armature moves it breaks the electrical contact at the screw, cutting off the current flow, and the cycle of operations begins again and is repeated many times a second.