40+ Electrical Designer Interview Questions and Answers

Cable tray layout involves designing and arranging cable trays for efficient cable management.

• Input requirements include cable type, size, weight, and routing

• Trench layout input requirements include trench dimensions and depth

• Design should consider cable spacing, support, and accessibility

• Proper grounding and bonding should also be considered

A panel is an enclosure that houses electrical components and controls. Yes, I have worked in panel layout.

• Panels are used to protect electrical equipment from damage and to prevent electrical hazards.

• Panel layout involves designing the arrangement of components within the panel.

• Factors to consider in panel layout include ease of access, cable routing, and heat dissipation.

• Examples of components that may be included in a panel are circuit breakers, relays, and switches.

To create a block in electrical design, follow these steps for block editing.

• Open the schematic editor and draw the desired shape for the block

• Select the shape and right-click to access the 'Create Block' option

• Name the block and add any necessary attributes

• Save the block to the library for future use

• To edit the block, select it and right-click to access the 'Edit Block' option

• Make the desired changes and save the updated block to the library

To shift a drawing from one window to another, use the MOVE command.

• Type MOVE in the command line

• Select the drawing to be moved

• Specify the base point of the drawing

• Select the destination window

• Specify the insertion point in the destination window

Amperage and kilowatt ratings can be calculated using Ohm's Law and power formulas, essential for electrical design.

• Ohm's Law: Amperage (I) can be calculated using the formula I = V/R, where V is voltage and R is resistance. Example: For 120V and 60Ω, I = 120/60 = 2A.

• Power Formula: Kilowatt rating (P) can be calculated using P = VI, where V is voltage and I is current. Example: For 240V and 10A, P = 240 * 10 = 2400W or 2.4kW.

• Three-Phase Power: For three-phase systems, P = √3 ...read more

To convert kilowatts to amps, use the formula: Amps = Kilowatts / Voltage, considering the power factor for AC circuits.

• Formula: Amps = kW / Voltage. For example, 10 kW at 240V equals 10 / 240 = 0.0417 A.

• For AC circuits, consider the power factor: Amps = kW / (Voltage x Power Factor). Example: 10 kW at 240V with a power factor of 0.9 equals 10 / (240 x 0.9) = 0.0463 A.

• In DC circuits, the formula simplifies to Amps = kW / Voltage since the power factor is 1.

• Always ensure volta...read more

First angle and third angle projection are two methods used in technical drawing to represent a 3D object on a 2D surface.

• First angle projection is commonly used in Europe and Asia, where the object is imagined to be in the first quadrant of a Cartesian coordinate system.

• Third angle projection is commonly used in North America, where the object is imagined to be in the third quadrant of a Cartesian coordinate system.

• In first angle projection, the top view is placed above the ...read more

Standard size and length of cable tray varies depending on the application and requirements.

• Standard sizes for cable trays are typically 4, 6, 8, 12, 18, and 24 inches wide.

• Standard lengths for cable trays are usually 10 or 12 feet long.

• The size and length of cable tray needed will depend on the amount and type of cables being supported.

• Consider factors such as weight capacity, corrosion resistance, and environmental conditions when selecting cable tray size and length.

Transformers and generator alternators are devices that convert electrical energy from one form to another.

• Transformers work on the principle of electromagnetic induction, where a changing current in one coil induces a voltage in another coil.

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

• Generator alternators, also known as synchronous generators, convert mechanical energy into electrical energy through the prin...read more

Different types of earthing gistrips include plate earthing, pipe earthing, and rod earthing.

• Plate earthing involves burying a copper plate in the ground.

• Pipe earthing uses a galvanized iron pipe filled with charcoal and salt to improve conductivity.

• Rod earthing utilizes a copper rod driven into the ground to provide a low-resistance path for fault currents.

The National Electrical Code (NEC) is used in the USA.

• The NEC is updated every three years.

• It is published by the National Fire Protection Association (NFPA).

• The NEC covers electrical wiring and installations in buildings and structures.

• It is adopted by most states and local jurisdictions in the USA.

• The current version of the NEC is the 2020 edition.

UPS provides instant backup power during outages, while inverter converts DC power to AC power.

• UPS stands for Uninterruptible Power Supply and provides instant backup power during outages.

• Inverter converts DC power from batteries or solar panels to AC power for household appliances.

• UPS typically has a battery backup to provide continuous power, while inverters rely on external power sources.

• UPS is commonly used for critical equipment like computers and servers, while inverter...read more

CSD stands for Current Source Density.

• CSD is a technique used in neuroscience to analyze the distribution of electrical currents in the brain.

• It helps in understanding the flow of electrical activity and identifying regions of neural activity.

• CSD is often used in conjunction with techniques like electroencephalography (EEG) or electrocorticography (ECoG).

LOP stands for Line of Position.

• LOP is a navigational term used in marine and aviation industries.

• It refers to a line on a chart or map that represents the position of a vessel or aircraft at a specific time.

• LOP is determined by taking bearings or angles to known landmarks or navigational aids.

• By intersecting multiple LOPs, the exact position of the vessel or aircraft can be determined.

• LOP is crucial for navigation and ensuring the safety of the vessel or aircraft.

sed is a command-line text editor used for stream editing and manipulating text.

• sed stands for 'stream editor'

• It is used for performing text transformations on input streams or files

• sed uses regular expressions to match and modify text

• It can be used to search, replace, insert, delete, and transform text

• Example: sed 's/old/new/g' file.txt replaces all occurrences of 'old' with 'new' in file.txt

Designing a 100 kv Single Line Diagram on AutoCAD.

• Create a new drawing in AutoCAD.

• Use appropriate symbols for electrical components.

• Draw the lines and connect the components to create the SLD.

• Label the components and lines with appropriate text.

• Ensure the SLD is accurate and meets all necessary standards.

• Save and submit the final design.

Star-delta starter is a type of reduced voltage starter used in induction motors to reduce starting current.

• Consists of a star contactor for starting and a delta contactor for running

• Reduces starting current by initially connecting the motor windings in star configuration

• Switches to delta configuration once motor reaches desired speed

• Commonly used in applications where high starting current is a concern

OHE stands for Overhead Equipment.

• OHE is a system used in railways for supplying electricity to trains through overhead lines.

• It includes components like catenary wires, droppers, insulators, and feeder pillars.

• OHE is essential for the operation of electric trains, providing power for traction motors.

• Regular maintenance of OHE is crucial to ensure safe and efficient train operations.

To make a group, identify common interests, invite potential members, establish goals and guidelines, and communicate regularly.

• Identify common interests among potential members

• Invite potential members to join the group

• Establish goals and guidelines for the group

• Communicate regularly to ensure everyone is on the same page

SSP stands for System Security Plan, which is a document outlining the security measures and protocols for a specific system or project.

• SSP is a detailed document that includes information on security controls, risk assessments, security policies, and procedures.

• It outlines how sensitive information will be protected, who has access to it, and how incidents will be handled.

• Examples of components in an SSP include access control measures, encryption protocols, and incident res...read more

Types of induction motors include single-phase, three-phase, squirrel cage, and wound rotor motors.

• Single-phase induction motors are commonly used in household appliances.

• Three-phase induction motors are widely used in industrial applications.

• Squirrel cage motors have a simple and rugged construction.

• Wound rotor motors allow for external resistance to be added for speed control.

Tray sizes vary depending on the application and can range from 2 inches to 36 inches in width.

• Tray sizes are determined by the amount and size of cables or wires being carried.

• Common tray sizes include 12 inches, 18 inches, and 24 inches in width.

• Tray depths can range from 1.5 inches to 6 inches.

• Tray materials can include aluminum, steel, or fiberglass.

• Tray types include ladder, solid bottom, wire mesh, and cable tray.

• Tray dimensions should be selected based on the specific ...read more

Software knowledge is essential for an Electrical Designer to effectively design and analyze electrical systems.

• Proficiency in CAD software such as AutoCAD or SolidWorks is crucial for creating detailed electrical drawings

• Knowledge of simulation software like MATLAB or PSpice helps in analyzing and optimizing electrical circuits

• Familiarity with programming languages like C++ or Python can be beneficial for automation and control systems design

To make a block, create a 3D model using CAD software and save it as a block. It can then be inserted into other drawings.

• Create a 3D model using CAD software

• Select the model and save it as a block

• Give the block a name and description

• Insert the block into other drawings as needed

TTC in railway stands for Time to Collision, which is a measure of the time it will take for two objects to collide if they continue on their current path.

• TTC is used in railway signaling systems to prevent collisions between trains.

• It calculates the time it will take for a train to reach a certain point based on its current speed and distance.

• TTC is crucial for ensuring the safety and efficiency of railway operations.

I specialize in designing electrical systems for various applications, focusing on efficiency and safety.

• Expertise in power distribution systems, ensuring optimal load management.

• Experience with lighting design, including energy-efficient solutions.

• Proficient in using CAD software for circuit design and layout.

• Knowledge of industry standards and regulations, such as NEC and IEC.

• Familiar with renewable energy systems, including solar and wind integration.

Star delta starter is used to reduce the starting current of induction motors.

• Reduces starting current by initially connecting the motor windings in a star configuration and then switching to delta configuration.

• Used for large induction motors to prevent damage to the motor and reduce voltage drop in the supply.

• Commonly used in industries where high starting torque is required, such as in conveyor belts or pumps.