Tuesday, February 24, 2015

What is UPS ?

UPS : Uninterruptible power supply .

UPS 
  In general , a UPS contains a rechargeable battery and DC to AC convert circuitry . The battery charging circuitry in the UPS will maintain the battery at a full charge during normal operation . If the AC  power supply falls low or goes off for any reason , the inverter automatically turns on to maintain the 230 volt AC power supply  instantly , no any change UPS output power . Its called UPS .You can continue to work on the computer , either until the UPS battery discharges ,or until the AC power comes back . At the very least ,this will give you enough time to save files and shut down your computer system normally .

HOW TO MAKE A UPS ...........Coming soon .


UPS BLOCK DIAGRAM 


Sunday, February 22, 2015

What is inductors ?

Inductors : Basically , inductors are coils that have large inductance . They oppose the change of current flowing through them , and are used in power supplies for filtering out ripples .

Their principle of working is explained below .
 We know that  the flow of current through a conductor is accompanied by magnetic effects . The transfer of electrical energy to the magnetic field represents work done by the source of emf . power is required for doing work , and since power is equal to current multiplied by voltage ,there must be a voltage drop in the circuit during the time which energy is being stored in the field .This voltage '' drop'' (which has nothing to do with the voltage drop in any resistance in the circuit ) is the result of an opposing voltage value .When the field becomes constant the induced emf or back emf disappears,since no further energy is being stored . Since the induced emf opposes the emf of the source , it tends to prevent the current from rising rapidly when the circuits is closed .The amplitude of the induced emf is proportional to the rate at which the current is changing and to a constant associated with the circuit itself , called the inductance of the circuit .

Thursday, February 19, 2015

Rectifiers

Introduction : As most of the electronic equipment need a DC supply , the stepped-up or stepped down AC available from the transformer has to be converted first into a unidirectional voltage by rectification and then ripples removed by adding a filter circuit to get a smooth DC voltage . Every AC to convert DC circuit need rectifiers .
definition : A rectifier is a device which allows current to flow in one direction only .

Transformer and Transformer winding

Introduction : Transformer is AC device .It is work AC supply only .
Definition : Transformer is a device which is Chang AC voltage .