10+ Electrical Design Engineer Interview Questions and Answers for Freshers

Load list preparation involves identifying all electrical loads in a system and determining their power requirements to size transformers.

• Identify all electrical loads in the system, including lighting, equipment, HVAC, etc.

• Determine the power requirements of each load in terms of voltage, current, and power factor.

• Sum up the power requirements of all loads to calculate the total load on the system.

• Select an appropriate transformer size based on the total load and any future ...read more

Softwares used in Electrical Engineering include CAD, simulation, and analysis tools.

• CAD software like AutoCAD and SolidWorks are used for designing electrical systems and components

• Simulation software like MATLAB and Simulink are used to model and simulate electrical systems

• Analysis software like ETAP and PSCAD are used to analyze and optimize electrical systems

• Other software like LabVIEW and Altium Designer are also used in Electrical Engineering

Current can be calculated using the formula: Current (A) = Power (kW) / (sqrt(3) x Voltage (V) x Power Factor)

• Use the formula: Current (A) = Power (kW) / (sqrt(3) x Voltage (V) x Power Factor)

• Make sure to convert kW to W if necessary (1 kW = 1000 W)

• Ensure the power factor is a decimal value, not a percentage (e.g. 0.85 instead of 85%)

Power and control wiring of star delta starter involves connecting the motor to the power supply and control circuit using a specific wiring diagram.

• Power wiring involves connecting the three-phase power supply to the motor through the main contactor.

• Control wiring involves connecting the control circuit to the motor through the timer and the star-delta contactor.

• During starting, the motor is connected in star configuration to reduce the starting current and then switched to ...read more

Microgrid is a localized group of electricity sources and loads that normally operates connected to and synchronous with the traditional centralized grid.

• Microgrid is a small-scale power grid that can operate independently or in conjunction with the main power grid.

• It can include distributed energy resources like solar panels, wind turbines, and batteries.

• Microgrids are often used to increase energy reliability, reduce costs, and integrate renewable energy sources.

• As an elect...read more

The order of cable sizes from 4 sqmm is 6 sqmm, 10 sqmm, 16 sqmm, 25 sqmm, 35 sqmm, 50 sqmm, 70 sqmm, 95 sqmm, 120 sqmm, 150 sqmm, 185 sqmm, 240 sqmm, 300 sqmm, 400 sqmm, 500 sqmm, 630 sqmm, 800 sqmm, 1000 sqmm.

• 6 sqmm

• 10 sqmm

• 16 sqmm

• 25 sqmm

• 35 sqmm

• 50 sqmm

• 70 sqmm

• 95 sqmm

• 120 sqmm

• 150 sqmm

• 185 sqmm

• 240 sqmm

• 300 sqmm

• 400 sqmm

• 500 sqmm

• 630 sqmm

• 800 sqmm

• 1000 sqmm

A,B,C & D type switchgears are different classifications based on their design and application in electrical systems.

• A type switchgears are suitable for low voltage applications

• B type switchgears are designed for medium voltage applications

• C type switchgears are used for high voltage applications

• D type switchgears are specifically designed for extra high voltage applications

Revit and AutoCAD are computer-aided design software used in architecture, engineering, and construction industries.

• Revit is a BIM (Building Information Modeling) software used for 3D modeling, design, and documentation of building projects.

• AutoCAD is a CAD (Computer-Aided Design) software used for 2D and 3D drafting, modeling, and visualization of various designs.

• Both software are widely used in the AEC (Architecture, Engineering, and Construction) industries for designing a...read more

Electricity is the flow of electrons through a conductor.

• Electricity is a form of energy that powers most of our modern devices.

• It is created by the movement of electrons from one atom to another.

• Electricity can be generated from various sources such as coal, wind, solar, and hydro power.

• It can be dangerous if not handled properly and can cause electric shock or fire.

• Electricity is measured in units of volts, amps, and watts.

Voltage drop calculation parameters include conductor material, length, cross-sectional area, current, and temperature.

• Conductor material affects resistance and therefore voltage drop.

• Length of the conductor directly impacts voltage drop.

• Cross-sectional area of the conductor affects resistance and voltage drop.

• Current flowing through the conductor influences voltage drop.

• Temperature can also affect the resistance of the conductor and subsequently voltage drop.

Eplan is a software used for electrical design engineering to create project reports.

• Eplan allows for efficient creation of electrical schematics and documentation

• It helps in automating repetitive tasks and ensuring consistency in designs

• Eplan can generate reports for bill of materials, wiring diagrams, and panel layouts

• The software also facilitates collaboration among team members working on the same project

Earthing calculation steps involve determining the resistance of the earthing system to ensure safety and proper functioning of electrical equipment.

• Determine the soil resistivity of the area where the earthing system will be installed.

• Calculate the required earth resistance based on the type of installation and equipment being used.

• Select the appropriate type and size of earthing electrodes based on the calculated resistance.

• Design the layout of the earthing system to ensure...read more

Lightning calculation steps involve determining the distance of a lightning strike based on the time delay between seeing the flash and hearing the thunder.

• Measure the time delay between seeing the lightning flash and hearing the thunder.

• Divide the time delay by 5 to get the distance in miles.

• For example, if the time delay is 10 seconds, the lightning struck 2 miles away.

• Remember that sound travels at approximately 1 mile every 5 seconds.

Different types of starters include DOL starter, star-delta starter, auto transformer starter, and soft starter.

• Direct Online (DOL) starter: provides full voltage to the motor at start

• Star-delta starter: reduces the starting current by initially connecting the motor in star configuration and then switching to delta

• Auto transformer starter: uses an auto transformer to reduce the voltage during starting

• Soft starter: gradually increases the voltage to the motor to reduce the sta...read more

LSIG protection refers to Long-Time, Short-Time, Instantaneous, and Ground fault protection settings in circuit breakers.

• LSIG protection is commonly used in circuit breakers to provide comprehensive protection against various types of faults.

• Long-Time setting protects against overloads by allowing the circuit breaker to trip after a specified time delay.

• Short-Time setting protects against short circuits by tripping the circuit breaker faster than the Long-Time setting.

• Instant...read more