JSW Group Electrical Engineer Interview Questions and Answers

A step up transformer is a type of transformer that increases the voltage level from the input side to the output side.

• Consists of more turns on the secondary coil than the primary coil

• Used to increase voltage levels for long distance power transmission

• Commonly found in power distribution systems and electrical grids

A distribution transformer is a device used to step down high voltage electricity to a lower voltage suitable for use in homes and businesses.

• Converts high voltage electricity from power lines to lower voltage for distribution

• Commonly used in electrical distribution systems

• Helps reduce voltage for safe use in homes and businesses

• Can be mounted on poles or placed on the ground

• Examples: pole-mounted distribution transfor

An alternator is a device that converts mechanical energy into electrical energy in the form of alternating current.

• An alternator is commonly used in vehicles to charge the battery and power the electrical system.

• It consists of a rotor, stator, diode rectifier, and voltage regulator.

• Alternators produce alternating current (AC) which is then converted to direct current (DC) for use in the vehicle.

• They are more efficient...read more

A synonyms machine is a tool or software that helps find alternative words with similar meanings for a given word.

• A synonyms machine can be a thesaurus or a feature in word processing software.

• It helps writers and speakers find the right word to convey their message effectively.

• Examples include online thesauruses like Thesaurus.com or built-in thesaurus in Microsoft Word.

A hysteresis motor is a type of synchronous motor that operates based on the hysteresis effect in magnetic materials.

• Hysteresis motors have a rotor made of a magnetic material with high hysteresis, such as cobalt steel.

• They do not require a separate DC excitation like other synchronous motors.

• Hysteresis motors are known for their smooth operation and low noise levels.

• They are commonly used in applications where precise...read more

Improving power factor helps in reducing energy losses, increasing system efficiency, and reducing electricity costs.

• Improving power factor reduces the amount of reactive power flowing in the system, which in turn reduces energy losses.

• Higher power factor means more efficient use of electricity and less strain on the electrical system.

• Improving power factor can lead to reduced electricity costs for consumers and utilit...read more

Buccholz relay is a protective device used in oil-filled transformers to detect faults such as internal arcing or overheating.

• Buccholz relay is installed in the oil pipe connecting the transformer tank and conservator tank.

• It works based on the principle that gas is generated when a fault occurs in the transformer, causing oil level to drop and gas to accumulate in the relay.

• The relay consists of two float switches - o...read more

DP in Siemens communication stands for Distributed Peripherals.

• DP is a communication protocol used by Siemens for connecting distributed peripherals to a central control system.

• It allows for real-time data exchange between the peripherals and the control system.

• DP is commonly used in industrial automation applications.

• Examples of DP communication modules include DP/DP couplers and DP slaves.

To communicate S7 PLC and ABB drive using Profibus, you need to configure the Profibus network, set up the communication parameters, and establish the communication link.

• Configure the Profibus network by setting the correct baud rate, address, and other network parameters.

• Set up the communication parameters on both the S7 PLC and ABB drive to ensure they are compatible with each other.

• Establish the communication link b...read more

Starters are used to control the starting and stopping of motors. Different types of starters are used based on the motor's power rating and application.

• Direct On-Line (DOL) Starter

• Star-Delta Starter

• Auto Transformer Starter

• Soft Starter

• Variable Frequency Drive (VFD) Starter

Parallel operation of transformers refers to connecting two or more transformers with the same voltage ratio and frequency to supply a common load.

• Parallel operation increases the capacity of the system and provides redundancy.

• The transformers must have the same voltage ratio, impedance, and phase angle.

• Proper synchronization is necessary to avoid circulating currents.

• Parallel operation can be achieved by using a commo...read more

A thyristor is a semiconductor device that acts as a switch and can handle high voltages and currents.

• It has three terminals: anode, cathode, and gate

• It can be turned on by applying a small current to the gate terminal

• It can handle high power and is commonly used in power control applications

• Examples include AC motor speed control, lighting dimming, and power supplies