CHAPTER ONE

A transformer is a magnetically coupled coil used in transmission of an electric power.
This coil may be electrically link, but not electrically linked as in two winding transformer.
It consists of primary winding and secondary winding which the number of turns varies depending on the type of transformer. Transformers are operated by the principle of mutual inductance between two separate coils wound on the same core.

There is also the step – up and step – down transformer. This work looks into the construction of a step – up auto transformer.

auto – transformer is the transformer that consists of only one is winding port of the being common to both primary winding and secondary winding.

That theory of an auto transformer and it operation is similar to that of the two winding transformer, it has high efficiency where cheap (because it used less copper) it is applicable where transformer ratio is little differs from unity.

1.2 PURPOSE
This transformer is a step – up transformer, it help in stepping up voltage, because of the primary winding function and the secondary winding function from the voltage rating to the normal rating is to step – up voltage in the transformer.   
1.3 OBJECTIVE
This transformer consists of only one winding part of the common to both primary and secondary winding. It had high efficiency and uses less copper, it is applicable where transformer ratio is differ from unity. The primary winding is connected to the power source and the other winding are secondary winding it help the transformer in increase the voltage to the normal voltage rate.
1.4 SIGNIFICANCE
The R. Fienberg in “MODERN POWER TRANSFORMER PRACTICE” stated that a transformer has a significance rate that transformer machine in bringing down the voltage rate it’s the desire amount.
Transformer initially raises the generated voltage for efficient transmission over long distance and there after decrease the system voltage for local destruction and utilization.
1.5 LAMINATION
The transformer comprises of ‘E’ and ‘I’ laminated cores which was obtained from a scrub transformer and recycled. the process of recycling involve washing of core with fuel to removed the unwanted grease and then dry up and grease with new oil so as to prevent air gap. it also comprise of coil which bought fresh one in the market, switches, connector former and insulator to isolate the output and input wires from touching each others.
1.6 DEFINITIONS OF TERMS
a transformer is a magnetically coupled with coil as in show in fig.1.1, a transformer rescues input current and send output voltage, be it step – up or step – down transformer it used in transmission of an electric power.
1.6.1 STANDARD WIRE GUAGE: 
These are specific number of a wine (coil) it is used in this project to gauge on 17 which has a diagram of 1.422m.
1.6.2 TRANSFORMER:
It is a cutout shape rubber material with a hollow in the center and with grove around is to avoid electric link between the core and the coil.
1.6.3 VOLTMETER: 
This is the instrument used to measure the voltage across the circuit. It is connected in parallel to the winding.
1.6.4 INSULATOR: 
These are the material used to isolate two conductors from touching each other.
1.6.5 CASING:
The outer cover of the transformer this serve is from external hazard was made of metal as earlier stated in our previous chapter.
1.6.6 THE SWITCH:
This is a mechanical advice used to open and close a complete electric circuit. The multipurpose low voltage (AC) transformers are connected via switch to the power supply.
The primary winding is connected to the power source and the other winding are secondary winding
We have step – up transformer and step – down transformer. But in this context emphasis will be lay on the step – up auto transformer.