What is a transformer? Everything you need to know

Do you know what is a transformer? We got you!

A transformer is an electronic device that transfers electricity between two or more circuits. Transformers are used to increase or decrease the voltage of an AC (alternating current) signal.

But that is not all. Let’s take a closer look at these amazing devices!

what is a transformer

History of transformer

The transformer was invented by a Hungarian-born American engineer named Ottó Bláthy in 1884.

It is believed that he was inspired to create the device after seeing a failed experiment that involved sending electric currents through a metal sheet.


Working Principle of Transformer

The working principle of a transformer is based on the concept of induction. When power is applied to one coil, this generates an electromotive force in the other coil which causes it to magnetically polarize.

The end result is that currents are induced into one circuit which creates voltage that then changes their polarity.

What is the use of a transformer?

Transformers are typically used to reduce the voltage in an electrical circuit. This makes it safer for low-voltage equipment that are near sensitive electronic devices, as well as prevents damage to household wiring.

Transformers can also be used for distribution of power that is overloaded or lacks stability by taking the load off the supply line during peak times.

A transformer can be placed on different circuits depending on their needs which ensures that no overloads occur even if one circuit has a problem with its voltage requirements.

It also lets you adjust how much power you need at any given time so an electrical system doesn’t have to work too hard and wear out prematurely because all the transformers always have some load placed upon them.

Transformers parts

A transformer consists of a primary, secondary coil and a magnetic core. When power is applied to the primary circuit, the magnetic flux from this phase effects the secondary phase by deflecting some of these currents back into it.

This creates a voltage that is induced into the second coil which then changes its polarity. This happens because magnetic flux has been cut off from one coil and applied to another. The end result is that there is now an induced current in the secondary circuit as well as an alternation of voltage levels.

The primary and secondary coil can be connected in either series or parallel with each other, which will create different effects on the power transfer depending on the needs of that particular circuit

This construction allows for us to use one circuit for multiple purposes. If there is no need of the energy levels at a particular time, it can be transferred over to another circuit that might have a greater need for it.

transformer parts

How does a transformer work?

The basics of how a transformer works is that electricity flows through one coil of wire, which creates a magnetic field that then induces current into the others. This means that the primary gives power to the secondary coil in order to make it produce voltage.

The process starts when there is alternating current (AC) in the primary coil, which creates magnetism with a change in polarity back and forth between north and south. The magnetic field then moves outwards toward the secondary coil and eventually enters the first coil of wire.

The magnetic field moves through the first wire and has a change in polarity or direction, this then induces an electric current. This process repeats as many times as there are coils on the transformer. The strength of the voltage is affected by how many coils both on the primary and secondary circuit.

The magnetic field continues to move through the secondary coil of wire until it reaches the end, this then goes back into the first coil of wire. This makes it so there is mostly electricity in one direction rather than two different directions which would create an alternating current (AC).

Since energy is stored within the magnetic field of the transformer, there is no need for a second power supply.

In order for the transfer of energy from the primary to the secondary coil to work, they must be linked together in a closed circuit. This means that there is a continuous path so electricity can flow through them both.

The efficiency of a transformer depends on how many coils are on each side and also what type of metal they are made of.

An iron core increases the magnetic field strength, so this makes it easier for the magnetic field to go through each wire rather than pushing against it and getting stuck.

On top of that, transformers can be manufactured to increase the voltage while decreasing amperage. For example, an ammeter is used in order to measure the number of amperes that are flowing through a wire.

A voltmeter is used to measure how much voltage is present in an electric circuit. For this reason, they must be manufactured together in order to work correctly.

Just like any other electronic device, transformers can break down or short sometimes due to overload. When this happens, it might create a spark and burn the device out.

It is important to make sure that there is no electricity running through a transformer if you are performing any maintenance on it. This means that the power source should be cut off, for example with a circuit breaker to keep everyone safe.

Transformers types

  • Step up and Stepdown Transformer
  • Power Transformer
  • Distribution Transformer
  • Uses of Distribution Transformer
  • Instrument Transformer
  • Current Transformer
  • Potential Transformer
  • Single Phase Transformer
  • Three Phase Transformer

Step up and Stepdown Transformer

A step-up transformer is designed to produce an output voltage that is higher than the electric input voltage. They are used when you need a large amount of efficient power for a short time, but not all the time.

One example of this would be for people traveling in an airplane or working with electronic devices that use a lot of currents. These transformers are also used to power homes that have wind turbines or solar panels.

Step-down transformers are designed to reduce the voltage on an electric input so it can provide power at a lower voltage output.

This type of transformer is often used in households or computers where there is the constant use of energy or simple machineries being powered, such as lamps or lights.

Power Transformer

A power transformer transfers power, usually in large amounts. They are mainly used to send electricity over long distances through the electric grid. The power transformer takes low voltage electricity and converts it into high voltage electricity so it can travel long distances.

The transformer then changes back to a low voltage near the person or business who needs the power.

Distribution Transformer

The distribution transformer is designed to create a safe distribution system for electric current. They are primarily used for homes, offices, factories, and other facilities where energy needs are at different levels that require an even flow of power.

They reduce surging by regulating the flow of electricity that enters into homes and buildings.

The distribution transformer is not actually a transformer in the sense that it outputs a higher voltage than the input, however, it does allow for a safer and more efficient distribution of electricity.

This is made possible due to its primary function of transforming power from an electric grid down to a lower voltage so it can be used safely at homes and businesses.

Instrument Transformer

The instrument transformer is considered a special type of transformer device. It has the same functionality as a distribution transformer, but it is designed to handle an even lower load.

They are smaller in size and cheaper than other types of transformers, which makes them ideal for use with small appliances such as handheld power tools or microwaves.

Current Transformer

A current transformer is an instrument that allows for high-voltage measurements. It is called a current transformer because it inputs alternating current into the device and measures the amount of direct current coming out as a result.

Current transformers measure currents that are 10 to 100 times lower than voltage power, which makes them perfect instruments to use in measuring certain electrical equipment or devices.

Potential Transformer

A potential transformer is an instrument that transforms electrical voltage down to a more measuring-friendly level. The device inputs HV electricity and measures the amount of lower voltage electricity as a result.

Like current transformers, potential transformers allow for measurements on voltage levels 10 to 100 times smaller than those used by distribution transformers.

Single Phase Transformer

A single-phase transformer is a type of distribution transformer that distributes power at 120 volts. They are found in residential areas, commercial buildings, and giant power plants.

Single-phase transformers work with three-phase circuits where the input voltage is distributed through two or more conductors that are 120 degrees apart to reach the customer’s premises. The input voltage that enters into the kite is usually between 120 and 240 volts in North America.

Three Phase Transformer

A three-phase transformer is a type of transmission or distribution transformer that distributes power at 240 volts. In North American countries, the input voltage ranges from 208 to 230 volts.

The transformers are used to service large areas where many customers need electric power. The area serviced by a three-phase transformer will have three sets of wires coming from it, which are 120 degrees apart from one another, and each set supplies a different voltage.

The three-phase transformer has six secondary windings. These are used in various combinations to produce the desired voltage for each customer’s specific area.

The six secondary windings are split up into two types: high and low voltage. An example of this would be if there were three customers in an area supplied by a three-phase distribution transformer


We believe you now understand what is a transformer and why we cant live without them.