Protection from high temperature

Protection from moisture entering in oil

Protection from pressure loading in tank

Protection from both overloading and short circuit

To offer high inductance

To obtain required voltage ratio

To regulate the primary current

To stabilise input and output voltage

To avoid over loading

To maintain constant voltage

To reduce transformer losses

To easy distribution of 3 phase 4 wire system

Self induced emf

Mutually induced emf

Statically induced emf

Dynamically induced emf

Ratio test

Impulse test

Short circuit test

Open circuit test