Electricity & Megnetism

# What is difference between step up and step down transformer?

Transformer is an electrical device which is used to step up or step down ac voltage.There are two types of transformer,step up and step down.The difference between step up and step down transformer is that step up transformer increases the input voltage and step down transformer decreases the input voltage.

### Step up transformer

If (Ngreater than NP) and (Vis greater Vp) such a transformer in which voltage across secondary is greater than the primary voltage is called a step up transformer.A step up transformer has more turns in its secondary winding than its primary winding and is used to increase the ac voltage.

The turns ratio for a step up transformer is always greater than 1 because the number of turns in the secondary winding is always greater than the number of turns in the primary winding.

### Step down transformer

If (Ns is less then NP) the number of turns in the secondary is less than the number in primary,and (Vis less then Vp) ,such transformer in which voltage across secondary is less than the primary voltage is called a step down transformer.The turns ratio for a step down transformer is always less than 1 because the number of turns in the secondary winding is always fewer than the number of turns in the primary winding.