Khaitan Chemicals & Fertilizers Electrical Engineer Interview Questions and Answers

Starters are used to control the starting and stopping of motors. Types include DOL, star-delta, soft starters, and VFDs.

• Direct-On-Line (DOL) starters provide full voltage to the motor at start-up

• Star-Delta starters reduce the voltage during start-up to reduce inrush current

• Soft starters gradually increase the voltage to the motor to reduce inrush current and mechanical stress

• Variable Frequency Drives (VFDs) control th...read more

Transformers work on the principle of electromagnetic induction to transfer electrical energy between two or more circuits.

• Transformers have two coils of wire, known as primary and secondary coils, which are wound around a core made of ferromagnetic material.

• When an alternating current flows through the primary coil, it creates a changing magnetic field around the coil.

• This changing magnetic field induces a voltage in ...read more

Transformers are cooled using methods such as oil cooling, air cooling, and water cooling.

• Oil cooling: Transformers are immersed in oil to dissipate heat generated during operation.

• Air cooling: Fans are used to circulate air around the transformer to cool it down.

• Water cooling: Water is circulated around the transformer to absorb heat and cool it.

• Forced oil cooling: Oil is circulated through a heat exchanger to remove