What is function of auto transformer?

Answer 1

A transformer is a device that changes an electrical voltage or current from one level to another. (In radio frequency applications, it is used to couple the RF electronic circuits.)

Transformers are used to:

• Convert high voltage alternating current (AC) to desired low voltage alternating current (AC). Such transformers are called step down transformers.

• Convert low voltage alternating current (AC) to desired high voltage alternating current (AC). Such transformers are called step up transformers.

• Electrically separate one part of the circuit (or any other electrical system) from the other part, termed as 'electrical isolation'. Such transformers are called isolation transformers.

The transformation may involve the loss of some power as waste heat.

(see related question)

Answer 2

In computer power supplies, the transformers serve to lower the voltage coming in from the 120 volts (or 240 in some cases) coming from the outlet to 12v, 5v or 3.3v. Differrent components in the PC use one of these three voltages.

Answer 3

Autotransformers can be used as buck/boost transformers, increasing or decreasing a supply voltage by a small amount. They can also be used in place of a full transformer if the voltage ratio between the primary and secondary is fairly small (less than ~4). This can save cost in both physical equipment cost and area equipment takes up.

The supply voltage can only be decreased, but can not be increased using auto transformers.

Answer 4

Interconnecting transfomers are used to connect two EHV line at different voltages i.e. 220KV to 400KV. The interconnecting transformer are auto transformer which can step up & step down the voltages for synchronization of two grid voltages.

Answer 5

The primary winding is connected to the supply, and its function is to circulate a current that will magnetise the core. The secondary winding will supply the load, and its function to have the secondary voltage induced into it.

Answer 6

the use of transformer in electrical engg is to step up or step down the electrical quantities . they are used in substations to power supply. current , potential transformers are also used for measuring high current and voltages respectively.

small transformers are widely used in electronics circuits to step down the 230v supply voltage to 9,5v etc.

Answer 7

In home electronics, it changes 120volt AC electricity into (usually) 12volt or less DC electricity for use in small electronic items that do not need high voltage to operate.

Answer 8

to change voltage'