A transformer is a passive maker that counter the voltage level either from high to low or low to high. The transformer that converts the high voltage power to low voltage power is referred to as a step-down transformer and the one the converts short to high voltage is called a step-up transformer.

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A transformer functions on the shared induction principle, additionally known as Faraday’s law of Electromagnetic Induction, which says that the magnitude of voltage is directly proportional come the price of change of magnetic flux.

To gain a deeper view into the power of a transformer, let’s understand its basics.

Mutual Induction

It method that a present gets induced in a coil when it come in proximity that a current-carrying coil having varying magnetic flux. This induced existing is directly proportional to the price of change in current.

Faraday’s Law

According come the Faraday’s Law, any change in the magnetic ar near the coil or conductor leads to the manufacturing of one electromotive force (EMF) that is induced inside the coil due to a adjust in magnetic flux.


A transformer consists of the adhering to main parts:


The coils that space winded up on a specific material collectively type a transformer core. This cores room made of really high permeable product that is may be to bring the flux. The main point of a transformer acts together a route or channel for the easy flow of magnetic flux. These cores are built using ferromagnetic materials that have actually high permeability such together iron.

In transformers, we usage thin metallic stole sheets rather of a solitary solid core since the single solid core causes a greater generation the eddy currents and this reduce the performance of a transformer.


The transformers are winded v wires dubbed coils. Here, we use wires with much less resistance and great conductivity, i m sorry is forced to get an excellent efficiency indigenous the transformer. Generally, copper is provided in transformer winding together it has good electrical conductivity and an extremely low resistance in comparison to others. That is additionally not expensive choose gold, silver and platinum.


A transformer functions on the rule of shared induction. So, when there is a change in the existing of one coil, an electric existing is also induced in the various other coil in that is proximity.

Every transformer is composed of two coils or winding: primary and also secondary. The main winding is associated to the AC power source and the second to the load. As soon as AC existing is listed to the primary winding of the coil, a magnetic flux it s okay generated. V the transformer core, the magnetic field completes its path. As the second winding comes in call with this magnetic flux, one EMF is induced on it. The stamin of the generated EMF depends on the number of turns in winding of the second coil.


where, N1 = number of turns in the 1st coil

N2 = variety of turns in the second coil

The relation in between voltage and number of turns in a coil is:

Vp/ Vs = Np/Ns

where, Vp = Voltage in primary coil

Vs = Voltage in an additional coil

Np = variety of turns in major coil

Ns = variety of turns in an additional coil

Step under Transformer

What is a Step-Down Transformer?

The transformer that has a larger number of turns in the main winding and also a smaller sized number for second winding is called a action down transformer. So together we have the right to see from the previous equation for the relation in between the number of turns in winding and voltage, if the variety of turns in main is greater than the variety of turns in second then the EMF created in the secondary is less than the major input.

Hence, we obtain a lower voltage in the second coil the a action down transformer. Together the name indicates, the action down transformer is used for converting greater voltage power into lower voltage power.

Now let’s understand the above process with an example. Mean we have actually an AC source that can produce 210 V. If we use a transformer having actually Np (number of turns in the primary coil) = 20000 and also Ns (number of turns in secondary) = 100, then Vs (voltage at the second coil) is given by

Vs = (Vp * Ns)/Np

Put the over values in this equation to calculate the voltage in ~ the second coil. I have actually left this occupational for you. Point out the right value in the comments.

Step under Transformer Types

single phase action Down TransformersCenter phase action Down TransformersMulti tapped step Down Transformers

Application of Step-Down Transformer

Step under transformers are used in strength adaptors and rectifiers to effectively decrease the voltage. Castle are additionally used in digital SMPS.

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Other applications include:

Power infection linesWelding machinesVoltage stabilizers and also inverters

Advantages that Step-Down Transformers

Step-down transformers are really efficient and can offer the desired output through an effectiveness of as much as 99 every cent.We can obtain the preferred output voltage quickly without lose of lot power.They are much less expensive and much more reliable.They can be supplied to provide high currents and low voltages.