900+ Electrical Engineer Interview Questions and Answers

The two types of winding in electrical engineering are lap winding and wave winding.

• Lap winding is used in DC machines and is characterized by multiple parallel paths for current flow.

• Wave winding is used in AC machines and is characterized by a single path for current flow.

• Lap winding provides high current capacity and low voltage output, while wave winding provides low current capacity and high voltage output.

• In lap winding, the number of parallel paths is equal to the numb...read more

The current unit is the ampere (A), which measures the flow of electric charge.

• The unit of electric current is the ampere (A).

• Current is the rate of flow of electric charge.

• It is measured using an ammeter.

• One ampere is equal to one coulomb of charge passing through a point in one second.

A sensor is a device that detects and responds to some type of input from the physical environment.

• Sensors can be classified into various types such as temperature sensors, pressure sensors, proximity sensors, etc.

• They can be analog or digital, active or passive, and can use different sensing principles such as resistive, capacitive, inductive, etc.

• Sensors are widely used in various applications such as automotive, aerospace, medical, industrial, etc.

• Examples of sensors inclu...read more

My current payment is $80,000 annually before taxes and $65,000 after taxes.

• My current annual salary is $80,000 before taxes

• After taxes, my take-home pay is $65,000

• I receive a monthly salary of $6,666.67 before taxes

The P.I test in transformers is performed to determine the insulation condition and losses in the transformer.

• P.I test stands for Polarization Index test.

• It is a type of insulation resistance test.

• The test measures the ratio of insulation resistance at 10 minutes to the insulation resistance at 1 minute.

• The test helps in assessing the insulation condition and detecting any moisture or contamination in the transformer.

• A high P.I value indicates good insulation, while a low val...read more

DTR structure consists of transformer, rectifier, and filter components.

• Transformer: used to step down the voltage from the power source

• Rectifier: used to convert AC to DC

• Filter: used to smooth out the DC output

• Components may include diodes, capacitors, resistors, and inductors

• Example: DTR structure is commonly used in power supplies for electronic devices

VFD stands for Variable Frequency Drive. It is an electronic device that controls the speed of an AC motor.

• VFD is used to save energy by controlling the speed of the motor according to the load.

• It can also improve the lifespan of the motor by reducing wear and tear.

• VFD can be used in various applications such as pumps, fans, conveyors, and compressors.

• It works by converting the incoming AC power to DC and then back to AC at a variable frequency.

• VFD can provide precise control...read more

Safety instructions in previous plant included wearing appropriate PPE, following lockout/tagout procedures, and attending regular safety training.

• Wearing appropriate PPE (Personal Protective Equipment) such as safety glasses, gloves, and hard hats

• Following lockout/tagout procedures when working on electrical equipment to prevent accidental startup

• Attending regular safety training sessions to stay updated on safety protocols and procedures

C is a low-level programming language while Java is a high-level object-oriented language.

• C is a procedural language while Java is an object-oriented language.

• C has manual memory management while Java has automatic garbage collection.

• C is platform-dependent while Java is platform-independent.

• C supports pointers while Java does not.

• C is typically used for system-level programming while Java is used for application development.

The installation procedure of a new transformer involves testing the BDV of oil and filtering the oil.

• Inspect the site and ensure it meets safety requirements

• Transport the transformer to the site and position it correctly

• Connect the transformer to the electrical system

• Test the BDV of the oil to ensure it meets specifications

• Filter the oil to remove any impurities

• Fill the transformer with oil

• Test the transformer to ensure it is functioning properly

MCB stands for Miniature Circuit Breaker. It is an electrical switch that automatically shuts off the electrical circuit during an overload or short circuit.

• MCB is a type of circuit breaker that is commonly used in residential and commercial buildings.

• It is designed to protect electrical circuits from damage caused by overloading or short circuits.

• MCBs are available in different current ratings and can be easily replaced if they trip.

• They are more reliable and faster in tripp...read more

Different types of sources of electricity include fossil fuels, nuclear power, renewable energy sources, and batteries.

• Fossil fuels (coal, oil, natural gas)

• Nuclear power

• Renewable energy sources (solar, wind, hydro, geothermal)

• Batteries (lithium-ion, lead-acid)

Equipment required in HT and LT lines include transformers, circuit breakers, insulators, conductors, and lightning arresters.

• Transformers are used to step up or step down voltage levels in HT and LT lines.

• Circuit breakers are essential for protecting the lines from overloads and short circuits.

• Insulators are used to support and separate conductors to prevent electrical leakage.

• Conductors are used to carry the electrical current from one point to another.

• Lightning arresters p...read more

Handing over taking over certificate is a document used in engineering projects to officially transfer responsibility from one party to another.

• It is a formal document that signifies the transfer of responsibility from one party to another in engineering projects.

• It includes details such as the scope of work, completion status, quality standards, and any outstanding issues.

• The certificate is signed by both parties to acknowledge the handover and acceptance of the project.

• It i...read more

Feeder bifurcation is the process of dividing a main electrical feeder into multiple branches to distribute power to different areas.

• Feeder bifurcation involves splitting a main feeder into smaller branches to supply power to different sections of a building or facility.

• This process helps in balancing the load and preventing overloading of the main feeder.

• Feeder bifurcation can be done using distribution panels, circuit breakers, and switches.

• Examples of feeder bifurcation in...read more

Railway crossings are intersections where roads and railway tracks meet, requiring vehicles to stop when trains are passing.

• Railway crossings are equipped with warning signs, lights, and barriers to alert drivers of approaching trains.

• Drivers must stop behind the barriers when they are down and wait for the train to pass before proceeding.

• Some railway crossings also have bells or horns to further warn drivers of an approaching train.

• It is important for drivers to always be ca...read more

Sensors in a turbine are located at various points to monitor temperature, pressure, vibration, and speed.

• Sensors are typically located at the inlet and outlet of the turbine to monitor temperature and pressure.

• Vibration sensors are placed on the turbine shaft to detect any abnormal vibrations that could indicate potential issues.

• Speed sensors are used to monitor the rotational speed of the turbine blades.

• Examples of sensors used in turbines include thermocouples, pressure tr...read more

The number of wires that can be pulled through a 25mm conduit pipe depends on the size and type of the wires.

• The number of wires that can be pulled through a conduit pipe depends on the size of the wires and the size of the conduit pipe.

• Thinner wires will allow for more wires to be pulled through compared to thicker wires.

• For example, if using standard 2.5mm² wires, you may be able to pull around 4-6 wires through a 25mm conduit pipe.

The neutral wire and grounding serve different purposes in electrical systems.

• The neutral wire carries current back to the source in a balanced electrical circuit.

• Grounding provides a path for electrical faults to safely discharge into the ground.

• Neutral wire is typically connected to the center tap of a transformer, while grounding is connected to the earth.

• Neutral wire is part of the normal current-carrying circuit, while grounding is a safety measure to prevent electric sh...read more

The ohmic value of PT-100 is 100 ohms at 0°C.

• PT-100 is a type of platinum resistance thermometer.

• It has a resistance of 100 ohms at 0°C.

• The resistance increases with temperature at a rate of 0.385 ohms/°C.

• PT-100 is commonly used in industrial temperature measurement applications.

A transformer is an electrical device that transfers electrical energy from one circuit to another through electromagnetic induction. Protection of transformer involves measures to prevent damage to the transformer due to various factors.

• Transformers are used to step up or step down voltage levels in power transmission and distribution systems.

• They consist of two coils, primary and secondary, wound around a common magnetic core.

• Protection of transformer involves measures such...read more

A substance has resistance due to the opposition it offers to the flow of electric current.

• Resistance is caused by collisions between electrons and atoms in the substance.

• The resistance of a substance depends on its physical properties such as length, cross-sectional area, and temperature.

• Some substances have higher resistance than others, such as insulators compared to conductors.

• Resistance can be measured in ohms using Ohm's law.

VBD test is conducted in transformers to ensure insulation integrity and detect any potential faults.

• VBD test helps in identifying any weak spots in the insulation of the transformer

• It helps in preventing breakdowns and ensuring the safety and reliability of the transformer

• By conducting VBD test, any potential faults can be detected early and necessary maintenance can be carried out

• It is a standard procedure in transformer testing to ensure optimal performance

The output voltage of an AAAC Rabbit conductor is typically around 600 volts.

• The output voltage of an AAAC Rabbit conductor is usually around 600 volts.

• The exact output voltage may vary depending on the specific application and conditions.

• It is important to consult the manufacturer's specifications for accurate information.

Current is the flow of electric charge, while voltage is the force that drives the current.

• Current is the rate of flow of electric charge through a conductor.

• Voltage is the difference in electric potential between two points in a circuit.

• Current is measured in Amperes (A), while voltage is measured in Volts (V).

• Ohm's Law relates current, voltage, and resistance in a circuit: V = I * R.

• In a simple analogy, current is like the flow of water in a pipe, while voltage is like the ...read more

I have worked with synchronous alternators and have experience in transformer maintenance.

• Worked with synchronous alternators in power generation applications

• Performed maintenance on transformers to ensure proper functioning

• Experience in troubleshooting and repairing electrical equipment

• Knowledge of safety protocols and regulations in electrical engineering

• Collaborated with team members to complete projects efficiently

The natural role of my work as an Electrical Engineer is to design, develop, and maintain electrical systems and equipment.

• Designing electrical systems for buildings, power plants, or industrial facilities

• Developing electrical schematics and blueprints

• Testing and troubleshooting electrical equipment

• Ensuring compliance with safety standards and regulations

• Collaborating with other engineers and professionals on projects

• Providing technical support and guidance to clients or coll...read more

The heat producing components in this room include computers, servers, lighting fixtures, and HVAC systems.

• Computers

• Servers

• Lighting fixtures

• HVAC systems

Diesel generator is a backup power source using diesel fuel, transformer is a device that transfers electrical energy between circuits, and HVAC is a system for heating, ventilation, and air conditioning.

• Diesel generator: provides backup power using diesel fuel, commonly used in areas with frequent power outages

• Transformer: transfers electrical energy between circuits, stepping up or down voltage levels as needed

• HVAC: system for heating, ventilation, and air conditioning, use...read more

Pulse width modulation (PWM) is a technique used in VFD to control the speed of the motor by adjusting the width of the pulses of voltage supplied to the motor.

• PWM is a method of controlling the amount of power delivered to a load without changing the voltage level.

• In VFD, PWM is used to control the speed of the motor by varying the width of the pulses of voltage supplied to the motor.

• The width of the pulses is controlled by a microprocessor that adjusts the frequency of the ...read more

Resistance is the opposition to the flow of electric current, capacitor stores electrical energy, star delta connection is a method of connecting three-phase electrical motors.

• Resistance is measured in ohms and is used to limit the flow of current in a circuit.

• Capacitors are used to store electrical energy and release it when needed. They are commonly used in electronic circuits to filter out unwanted frequencies.

• Star delta connection is a method of connecting three-phase ele...read more

Voltage is the unit of measurement for electric potential difference.

• Voltage is the force that pushes electric charges through a circuit.

• It is measured in volts (V).

• Voltage is essential for the operation of electrical devices.

• Examples of voltage units include millivolts (mV), kilovolts (kV), and megavolts (MV).

DG Automation refers to the automation of Diesel Generator systems.

• DG Automation involves the use of control systems and software to monitor and control the operation of Diesel Generator sets.

• It helps in optimizing the performance and efficiency of the DG sets.

• DG Automation can include features like remote monitoring, automatic start/stop, load sharing, fault detection, and protection.

• It can also involve integration with other systems like power management systems or building...read more

Incoming voltage high tension supply refers to the voltage level of the electrical power supply.

• The incoming voltage high tension supply is typically between 11 kV and 33 kV for industrial and commercial applications.

• It is important to ensure that electrical equipment is rated for the incoming voltage high tension supply to prevent damage or safety hazards.

• Transformers are often used to step down the incoming voltage high tension supply to a lower voltage level for use in bui...read more

Yes, I have experience with electrical simulation software.

• I have used software like MATLAB/Simulink for circuit analysis and simulation

• I have experience with PSpice for simulating electronic circuits

• I have utilized LTspice for designing and testing analog and digital circuits

To reduce load on a cable/conductor without introducing a capacitor, increase the conductor size, reduce the length of the cable, or use a higher voltage.

• Increase the conductor size to reduce resistance and therefore reduce load

• Reduce the length of the cable to decrease the amount of resistance

• Use a higher voltage to reduce the current flowing through the cable

A transformer is a device that transfers electrical energy between two or more circuits through electromagnetic induction.

• Transformers are used to increase or decrease voltage levels in electrical circuits.

• Mixer grinders typically use universal motors, which can run on both AC and DC power.

• AC current periodically changes direction, while DC current flows in one direction only.

• In India, the standard frequency is 50 Hz, while in the USA it is 60 Hz.

• Different types of motors inc...read more

Erection of transformer involves several steps including site preparation, foundation construction, assembly of transformer components, and testing.

• Site preparation involves clearing the area and ensuring proper drainage

• Foundation construction involves excavation, pouring concrete, and curing

• Assembly of transformer components includes positioning the core, winding the coils, and connecting the bushings

• Testing involves checking the insulation resistance, oil level, and other p...read more

The single line diagram of the plant I am working at shows the electrical connections and components in a simplified manner.

• The single line diagram typically includes power sources, distribution lines, transformers, circuit breakers, and loads.

• It provides a high-level overview of the electrical system without showing the physical location of each component.

• Symbols are used to represent different electrical components and their connections.

• The diagram helps in understanding th...read more

Battery sizing calculation involves determining the capacity and voltage required for a specific application.

• Determine the power requirements of the application

• Calculate the energy required by multiplying power and time

• Select a battery with sufficient capacity and voltage to meet energy requirements

• Consider factors such as temperature, discharge rate, and cycle life

• Perform testing and validation to ensure the selected battery meets the application's needs

Cable construction involves multiple layers for insulation and protection.

• Cables are typically constructed with multiple layers for insulation and protection.

• The innermost layer is the conductor, usually made of copper or aluminum.

• The next layer is the insulation, which can be made of materials like PVC, polyethylene, or rubber.

• Additional layers may include shielding to protect against electromagnetic interference.

• The outermost layer is the jacket, which provides mechanical p...read more

CEA guidelines, IS 3043, and OISD standards are important for ensuring safety in hazardous oil & gas installations.

• CEA guidelines provide recommendations for electrical installations in hazardous areas.

• IS 3043 specifies earthing standards to prevent electrical hazards.

• OISD standards focus on safety measures for oil & gas electrical systems.

• Compliance with these standards is crucial to prevent accidents and ensure worker safety.

• Examples of hazardous installations include oil r...read more

There are typically three levels of voltage used in industry: low voltage, medium voltage, and high voltage.

• Low voltage is typically used for lighting and small appliances

• Medium voltage is used for larger equipment and machinery

• High voltage is used for power transmission and distribution

• The specific voltage levels may vary depending on the industry and location

• Safety measures must be taken when working with high voltage systems

A transformer is a device that transfers electrical energy between two or more circuits through electromagnetic induction.

• Transformers consist of two coils of wire, known as the primary and secondary coils.

• The primary coil is connected to a power source, creating a magnetic field when current flows through it.

• This magnetic field induces a voltage in the secondary coil, transferring energy from the primary to the secondary circuit.

• Transformers are used to step up or step down ...read more

Drive components in CCM department are the parts that enable the motor to function properly.

• Drive components include motors, gears, belts, and pulleys.

• They work together to transfer power from the motor to the machine.

• The components must be properly sized and aligned to ensure efficient operation.

• Examples of machines that use drive components include conveyor belts, pumps, and fans.

The calculation to select electrical cable involves considering factors such as current rating, voltage drop, and environmental conditions.

• Determine the maximum current the cable will carry based on the load requirements

• Calculate the voltage drop to ensure it is within acceptable limits

• Consider the environmental conditions like temperature, moisture, and chemical exposure

• Select a cable with appropriate conductor size, insulation type, and voltage rating

• Refer to national and i...read more

Different types of conductors used for transmission systems include overhead lines, underground cables, and subsea cables.

• Overhead lines: commonly used for long-distance transmission, made of aluminum or copper conductors supported by towers or poles

• Underground cables: used in urban areas or sensitive environments, made of insulated conductors buried underground

• Subsea cables: used for underwater transmission, made of specially designed materials to withstand harsh marine cond...read more