23-02-2013, 02:16 PM
BATTERY ELIMINATOR
[attachment=51631]
INTRODUCTION
Battery Eliminator is a device used to convert high voltage alternating current (AC) into low voltage direct current (DC). A circuit arrangement is employed with which 220 volt alternating current is converted into 4½ volt direct current. Since with the help of this appliance, the use of the battery is eliminated, therefore it is known as a battery eliminator.
A battery eliminator is a device that provides an alternate source of power to a piece of equipment normally powered by batteries. Such devices can replace batteries for radios and other portable appliances. Electronics stores often carry them, along with accessories. It may also be possible to build one for a specific application, for people who are comfortable working with circuits and electrical components. Guides for custom-built devices are often available online, particularly through hobbyist and enthusiast pages for various types of battery-powered equipment.
Connecting with a source of power like a wall outlet or a solar panel, a battery eliminator processes the power, and provides a connection for the battery-powered device. It is important to use an appropriate eliminator, as the voltages such devices are designed to use can be quite variable. Simply plugging battery-powered appliances directly into an outlet can be dangerous, as can using the wrong battery eliminator to convert voltage to a usable form.
1) TRANSFORMER:
It is a device used to convert small alternating current at high voltage into low voltage alternating current or low voltage alternating current into high voltage alternating current. In our project we have used step-down transformer.
2) RECTIFIER:
It is a device used to convert alternating current into direct current. Rectifiers are of two types.
(i) Half wave rectifier
(ii) Full wave rectifier.
In our project we have used full wave rectifier to convert a full wave alternating current into full wave direct current.
TRANSFORMER...
The transformer is a device used for converting a low alternating voltage to a high alternating voltage or vice versa.
PRINCIPLE:
It is based on the principle of mutual induction that is if a varying current is set-up in a circuit, induced e.m.f. is produced in the neighbouring circuit. The varying current in a circuit produce varying magnetic flux which induces an e.m.f. in the neighbouring circuit.
STEP-DOWN TRANSFORMER:
In our project step-down transformer is used. This transformer converts high voltage alternating current into low voltage alternating current. In step-down transformer the number of turns in the primary coil is larger than the secondary coil.
CONSTRUCTION:
The transformer consists of two coils. They are insulated with each other by insulated material and wound on a common core. For operation at low frequency, we may have a soft iron. The soft iron core is insulated by joining thin iron strips coated with varnish to insulate them to reduce energy losses by eddy currents.
PRINCIPLE
It is based on the principle that a crystal diode conduct only in forward bias and then an output current flows in the circuit. When D1 is forward biased, D2 is reverse biased and vice-versa. The diode D1 and D2 send current through the load resistance in the same direction during both halves of the time period. This causes full wave rectification of the input power.
CONSTRUCTION
The full wave rectifier consists of two p-n junctions diodes connected to secondary part of the transformer. The input AC is applied across the primary coil (P) of a transformer. One terminal of the secondary coil (S) of the transformer is connected to the positive terminal of the junction diode D2. In the secondary part of the transformer a load resistance R1 is connected. The output is drawn across the two terminals of the load resistance.
WORKING
In case of a crystal diode as full-wave rectifier the two diodes D1 and D2 are used in such a way that during half cycle from 0 to II, crystal diode D1 becomes forward-bias and an output current I1 flows, similarly during next half cycle from II to 2II, crystal diode D2 becomes forward bias and an output current I2 flows in the circuit. In this way a crystal diode converts full wave alternating current into a full wave direct current.
[attachment=51631]
INTRODUCTION
Battery Eliminator is a device used to convert high voltage alternating current (AC) into low voltage direct current (DC). A circuit arrangement is employed with which 220 volt alternating current is converted into 4½ volt direct current. Since with the help of this appliance, the use of the battery is eliminated, therefore it is known as a battery eliminator.
A battery eliminator is a device that provides an alternate source of power to a piece of equipment normally powered by batteries. Such devices can replace batteries for radios and other portable appliances. Electronics stores often carry them, along with accessories. It may also be possible to build one for a specific application, for people who are comfortable working with circuits and electrical components. Guides for custom-built devices are often available online, particularly through hobbyist and enthusiast pages for various types of battery-powered equipment.
Connecting with a source of power like a wall outlet or a solar panel, a battery eliminator processes the power, and provides a connection for the battery-powered device. It is important to use an appropriate eliminator, as the voltages such devices are designed to use can be quite variable. Simply plugging battery-powered appliances directly into an outlet can be dangerous, as can using the wrong battery eliminator to convert voltage to a usable form.
1) TRANSFORMER:
It is a device used to convert small alternating current at high voltage into low voltage alternating current or low voltage alternating current into high voltage alternating current. In our project we have used step-down transformer.
2) RECTIFIER:
It is a device used to convert alternating current into direct current. Rectifiers are of two types.
(i) Half wave rectifier
(ii) Full wave rectifier.
In our project we have used full wave rectifier to convert a full wave alternating current into full wave direct current.
TRANSFORMER...
The transformer is a device used for converting a low alternating voltage to a high alternating voltage or vice versa.
PRINCIPLE:
It is based on the principle of mutual induction that is if a varying current is set-up in a circuit, induced e.m.f. is produced in the neighbouring circuit. The varying current in a circuit produce varying magnetic flux which induces an e.m.f. in the neighbouring circuit.
STEP-DOWN TRANSFORMER:
In our project step-down transformer is used. This transformer converts high voltage alternating current into low voltage alternating current. In step-down transformer the number of turns in the primary coil is larger than the secondary coil.
CONSTRUCTION:
The transformer consists of two coils. They are insulated with each other by insulated material and wound on a common core. For operation at low frequency, we may have a soft iron. The soft iron core is insulated by joining thin iron strips coated with varnish to insulate them to reduce energy losses by eddy currents.
PRINCIPLE
It is based on the principle that a crystal diode conduct only in forward bias and then an output current flows in the circuit. When D1 is forward biased, D2 is reverse biased and vice-versa. The diode D1 and D2 send current through the load resistance in the same direction during both halves of the time period. This causes full wave rectification of the input power.
CONSTRUCTION
The full wave rectifier consists of two p-n junctions diodes connected to secondary part of the transformer. The input AC is applied across the primary coil (P) of a transformer. One terminal of the secondary coil (S) of the transformer is connected to the positive terminal of the junction diode D2. In the secondary part of the transformer a load resistance R1 is connected. The output is drawn across the two terminals of the load resistance.
WORKING
In case of a crystal diode as full-wave rectifier the two diodes D1 and D2 are used in such a way that during half cycle from 0 to II, crystal diode D1 becomes forward-bias and an output current I1 flows, similarly during next half cycle from II to 2II, crystal diode D2 becomes forward bias and an output current I2 flows in the circuit. In this way a crystal diode converts full wave alternating current into a full wave direct current.