Design Engineer - Electrical Interview Questions and Answers in 2025 (100+ Q&A)

Ques:- What is Electrical Engineering?

Asked In :- Lennox,

Right Answer:
Electrical Engineering is a branch of engineering that deals with the study, design, and application of electrical systems, devices, and technologies, including circuits, power generation, electronics, and electromagnetism.

Design Engineer - Electrical Electrical

Ques:- What is the difference between effective earthing and resistive earthing?

Asked In :- ve commercial vehicles limited (a volvo group and eicher motors joint venture), murugappa group, croma, carl zeiss ab,

Right Answer:
Effective earthing refers to a grounding system that provides a low-resistance path for fault currents to safely dissipate into the earth, ensuring safety and equipment protection. Resistive earthing, on the other hand, intentionally introduces a resistance in the grounding path to limit fault currents, which can help in controlling overvoltages but may not provide the same level of safety as effective earthing.

Design Engineer - Electrical Electrical

Ques:- How does electrical train works and what type of motors are used to drive the train?which level of supply voltage is used?

Asked In :- Trane Technologies,

Right Answer:
An electric train works by using electricity to power electric motors that drive the wheels. The most common type of motor used is the three-phase induction motor or the DC motor. The supply voltage typically used for electric trains ranges from 600 to 25,000 volts, depending on the system and region.

Design Engineer - Electrical Electrical

Ques:- WHY POLARITY TEST OF CT IS VERY IMPORTANT IN SWITCHGEAR

Asked In :- E-T-A,

Right Answer:
Polarity testing of current transformers (CTs) is crucial in switchgear to ensure that the CTs are connected correctly in the circuit. Correct polarity ensures that the phase relationship between the primary and secondary sides is maintained, which is essential for accurate measurement and protection operation. Incorrect polarity can lead to malfunctions, false readings, and potential damage to equipment.

Design Engineer - Electrical Personal Questions round

Ques:- What is your achivment?

Asked In :- Cummins India, Sanmina Corporation, Kepler Communications, Recaero,

Right Answer:
One of my key achievements was leading a team to design and implement a new energy-efficient circuit that reduced power consumption by 30%, resulting in significant cost savings for the company.

Design Engineer - Electrical Electrical

Ques:- What is the function of RVT

Asked In :- rashmi group,

Right Answer:
RVT (Reactor Vessel Temperature) is used to monitor and control the temperature within a nuclear reactor's pressure vessel to ensure safe and efficient operation.

Design Engineer - Electrical Electrical

Ques:- Why we define potections of Tourbo generator in Class A & B.

Asked In :- L&T Metro Rail (Hyderabad), VECV, iacs,

Right Answer:
We define protections for turbo generators in Class A and B to ensure their safe operation and reliability. Class A protections are for immediate fault detection and isolation to prevent damage, while Class B protections are for monitoring and alarm functions to enhance operational safety and maintenance.

Design Engineer - Electrical Electrical

Ques:- WHICH TYPE OF TRANSFORMER USED IN SWITCHYARD IN POWER PLANT?

Asked In :- powerlink queensland, jtag technologies,

Right Answer:
The type of transformer used in a switchyard in a power plant is typically a **power transformer**.

Design Engineer - Electrical Electrical

Ques:- What do you mean by boost voltage in case of battery charger?

Asked In :- Teekay,

Right Answer:
Boost voltage in a battery charger refers to the increased voltage applied to the battery during the charging process to quickly raise its state of charge, especially when the battery is deeply discharged. This higher voltage helps to overcome the internal resistance of the battery and facilitates faster charging.

Design Engineer - Electrical Electrical

Ques:- What is the use of impulse line in AFBC boiler , WHY WECONNECT IMPULSE LINE TO TRANSMITTER , DRFT GAUGE ETC ????????

Asked In :- sna,

Right Answer:
The impulse line in an AFBC (Atmospheric Fluidized Bed Combustion) boiler is used to transmit pressure or flow measurements from the boiler to instruments like transmitters and draft gauges. It helps in accurately measuring the pressure drop across the fluidized bed, which is essential for monitoring and controlling the combustion process.

Design Engineer - Electrical Electrical

Ques:- Why usually in all electrical equipment taking more current in Y pahse like pumps,compressor,or any other applications

Asked In :- L&W Construction,

Right Answer:
In three-phase systems, the Y (or Wye) phase can draw more current due to unbalanced loads, phase angle differences, or specific design characteristics of the equipment, which may lead to higher current draw in that phase.

Design Engineer - Electrical Electrical

Ques:- What are the two types of noise of MOSFET, how to eliminatethem?(Thermal and Flicker).

Asked In :- Bharat Bijlee, E-T-A,

Right Answer:
The two types of noise in MOSFETs are:

1. **Thermal Noise**: This can be reduced by lowering the temperature of the device or using resistors with lower resistance values.

2. **Flicker Noise (1/f Noise)**: This can be minimized by using larger devices, optimizing the manufacturing process, or operating at higher frequencies where the flicker noise is less significant.

Design Engineer - Electrical Electrical

Ques:- How to improve IR value in HT motors?

Asked In :-

Right Answer:
To improve the Insulation Resistance (IR) value in high-tension (HT) motors, you can:

1. Ensure proper insulation materials are used and are in good condition.
2. Maintain optimal operating temperatures to prevent insulation degradation.
3. Regularly perform cleaning and maintenance to remove dust and moisture.
4. Use drying techniques, such as heating or applying a vacuum, to eliminate moisture.
5. Implement regular testing and monitoring of insulation resistance.
6. Avoid overloading the motor to reduce stress on the insulation.

Design Engineer - Electrical Electrical

Ques:- If transformer winding burn on dc supply then why not alternator rotor winding

Asked In :-

Right Answer:
A transformer winding burns on DC supply because it creates continuous current, leading to overheating. In contrast, an alternator rotor winding is designed to operate with AC, and when supplied with DC, it does not generate the same continuous magnetic field or overheating effect as a transformer, allowing it to withstand DC supply without burning out immediately.

Design Engineer - Electrical Electrical

Ques:- Why only three phase power generation are load are used

Asked In :- TC Energy, UOP Honeywell,

Right Answer:
Three-phase power generation is used because it provides a more efficient and stable power supply, allows for smaller and lighter conductors, and enables the use of smaller and more efficient motors compared to single-phase systems.

Design Engineer - Electrical Electrical

Ques:- Why we choose 400kv,220kv,132kv,66kv,33kv transmission voltages for transmitting power. Why not other voltage levels.

Asked In :-

Right Answer:
We choose 400kV, 220kV, 132kV, 66kV, and 33kV transmission voltages because these levels are optimal for minimizing power losses, ensuring efficient transmission over long distances, and balancing insulation requirements and equipment costs. Higher voltages reduce current, which decreases resistive losses, while these specific levels are standardized for compatibility with existing infrastructure and equipment.

Design Engineer - Electrical Electrical

Ques:- Which inert gas is flowing in tube light?

Asked In :- LGB,

Right Answer:
Neon or argon gas.

Design Engineer - Electrical Electrical

Ques:- Give me list of material for wiring of 20hp motor?

Asked In :- newcrest mining, vikram solar,

Right Answer:
1. Copper or aluminum wire (appropriate gauge)
2. Insulation (PVC or XLPE)
3. Conduit (PVC or metal)
4. Connectors (lugs, terminals)
5. Circuit breaker or fuse
6. Motor starter (contactor and overload relay)
7. Grounding wire
8. Junction boxes
9. Cable ties and clamps
10. Electrical tape

Design Engineer - Electrical Electrical

Ques:- Why 11KV/440V distribution supply use for Domestic use?

Asked In :- L&T Metro Rail (Hyderabad), ibi group,

Right Answer:
11kV/440V distribution supply is used for domestic use because it allows for efficient transmission of electricity over long distances with reduced losses, while 440V is suitable for safe and effective distribution to homes and small businesses.

Design Engineer - Electrical Electrical

Ques:- Corona happens more in ac or dc?

Asked In :- rebar design & detail (p) ltd,

Right Answer:
Corona happens more in AC (Alternating Current).

The Design Engineer – Electrical category on takluu.com is tailored for professionals and aspirants aiming to excel in electrical design roles. Electrical design engineers are responsible for planning, developing, and validating electrical systems for various applications, including power distribution, control systems, and electronics.

This section covers essential topics such as electrical circuit design, schematic diagrams, CAD software (like AutoCAD Electrical), wiring layouts, load calculations, and compliance with standards like IEC and NEC. You’ll also find questions related to design optimization, troubleshooting, protective devices, and safety protocols.

Interview questions often explore practical scenarios, for example:

“How do you approach designing a power distribution system?”
“Explain the use of AutoCAD Electrical in schematic design.”
“What factors do you consider for electrical load calculations?”

Our content presents complex design concepts in a clear and concise manner, supported by real-world examples and best practices. Whether you are fresh in the field or an experienced engineer, this category helps you prepare confidently for technical interviews and project discussions.

At Takluu, we keep this category updated with the latest tools, software advancements, and industry trends, ensuring you stay current and competitive in the electrical design domain.

Questions in: Design Engineer - Electrical

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