30+ Electrical Technician Interview Questions and Answers for Freshers

Electrical parts replacement involves choosing the right spare parts, removing the old parts correctly, making connections, and testing observations.

• Choose the correct spare parts before starting the replacement process

• Remove the old parts carefully and correctly to avoid damage to other components

• Make connections according to the manufacturer's instructions and double-check for accuracy

• Test the new parts thoroughly to ensure they are functioning properly

• Take notes or photos ...read more

Cable continuity can be checked using a multimeter or a cable tester.

• Use a multimeter to measure the resistance between the two ends of the cable. A low resistance value indicates continuity.

• Connect one end of the cable to the multimeter's positive lead and the other end to the negative lead.

• If the multimeter shows a high resistance or an open circuit, there is a break in the cable.

• Alternatively, a cable tester can be used to check continuity by sending a signal through the c...read more

There are several types of motor protection relays used in electrical systems.

• Motor overload protection relays

• Motor thermal protection relays

• Motor phase loss protection relays

• Motor short circuit protection relays

• Motor underload protection relays

• Motor earth fault protection relays

• Motor stall protection relays

The company generates 500 MW of energy.

• The company's energy generation capacity is 500 MW.

• The company has a power plant that generates 500 MW of energy.

• The energy output of the company is 500 MW.

• The company's energy generation is sufficient to power a large city.

The number of transformers depends on the specific context and location.

• The number of transformers can vary depending on the size and purpose of the electrical system.

• In a residential area, there may be one transformer serving multiple houses.

• In a commercial or industrial setting, there may be multiple transformers to meet the power demands.

• Transformers can also be found in power substations, where they step up or step down the voltage for transmission and distribution purpos...read more

Diode is a semiconductor device that allows current to flow in one direction. Capacitor stores electrical energy. Motor converts electrical energy into mechanical energy. Multimeter measures voltage, current, and resistance.

• Diode is a semiconductor device with two terminals that allows current to flow in one direction only.

• Capacitor is an electronic component that stores electrical energy and releases it when needed.

• Motor is a device that converts electrical energy into mecha...read more

The voltage in three-phase power systems is typically 208 volts, 240 volts, or 480 volts.

• Three-phase power systems are commonly used in industrial and commercial applications.

• The voltage in a three-phase system depends on the specific application and the power requirements.

• Common voltages in three-phase systems include 208 volts, 240 volts, and 480 volts.

• Higher voltage levels are typically used for larger industrial equipment and machinery.

• Lower voltage levels may be used for...read more

Star delta contactors are used in electrical systems to control the starting and stopping of three-phase motors.

• Star delta contactors are used to reduce the starting current of three-phase motors.

• They are commonly used in industrial applications where large motors are used.

• The contactors switch the motor windings from a star configuration to a delta configuration.

• This reduces the voltage across each winding and limits the inrush current during motor startup.

• Once the motor rea...read more

An electrician is a skilled tradesperson who installs, maintains, and repairs electrical systems and equipment.

• Electricians work with a variety of tools and equipment to install and repair electrical systems in buildings, homes, and other structures.

• They are responsible for reading and interpreting electrical blueprints and diagrams to determine the layout and installation of wiring, circuits, and other electrical components.

• Electricians must adhere to safety protocols and re...read more

Various faults can occur in high-tension (h.t) breakers.

• Short circuit fault

• Overload fault

• Mechanical fault

• Insulation fault

• Arcing fault

AHU stands for Air Handling Unit.

• AHU is a device used to regulate and circulate air as part of a heating, ventilation, and air conditioning (HVAC) system.

• It typically consists of a blower, heating or cooling elements, filters, dampers, and sound attenuators.

• AHUs are commonly found in commercial and industrial buildings to maintain indoor air quality and comfort.

• Examples of AHU manufacturers include Trane, Carrier, and Daikin.

Transformer works on the principle of electromagnetic induction.

• Transformers operate based on the relationship between magnetic fields and electric currents.

• They use two coils, primary and secondary, to transfer electrical energy from one circuit to another.

• The primary coil is connected to an alternating current (AC) source, creating a changing magnetic field.

• This changing magnetic field induces a voltage in the secondary coil, allowing energy transfer.

• Transformers are used i...read more

Transformers work by transferring electrical energy from one circuit to another through electromagnetic induction.

• Transformers consist of two coils of wire, a primary coil and a secondary coil, wrapped around a magnetic core.

• When an alternating current flows through the primary coil, it creates a magnetic field that induces a voltage in the secondary coil.

• The voltage in the secondary coil can be either higher or lower than the voltage in the primary coil, depending on the num...read more

The frequency in India is 50 Hz.

• The frequency of electrical power in India is standardized at 50 Hz.

• This frequency is used for both residential and commercial electricity supply.

• It is important for electrical technicians to be familiar with this frequency when working with electrical systems in India.

Electricity can be generated through various methods such as chemical reactions, electromagnetic induction, and photovoltaic effect.

• Chemical reactions, such as in batteries, can produce electricity.

• Electromagnetic induction, as in generators, converts mechanical energy into electrical energy.

• The photovoltaic effect in solar panels converts sunlight directly into electricity.

MCB stands for Miniature Circuit Breaker. Types of MCB include single pole, double pole, triple pole, and four pole.

• MCB stands for Miniature Circuit Breaker

• Types of MCB include single pole, double pole, triple pole, and four pole

A starter is an electrical device used to start a motor. There are various types of starters used in different applications.

• A starter is used to control the starting current of a motor.

• Direct-On-Line (DOL) starter is the simplest type of starter used for small motors.

• Star-Delta starter is used for larger motors to reduce the starting current.

• Soft starter is used to gradually increase the voltage to the motor to reduce the starting current.

• Variable Frequency Drive (VFD) starte...read more

APFC panel is used in industries to improve power factor and reduce energy consumption.

• APFC panel helps in maintaining a high power factor which reduces energy consumption and saves money.

• It also helps in reducing voltage drops and improves the efficiency of electrical equipment.

• APFC panel is commonly used in industries with high power consumption such as steel plants, cement factories, and chemical plants.

• It can also help in avoiding penalties from electricity boards for low...read more

Electricity is the flow of electric charge through a conductor.

• Electricity is a form of energy resulting from the movement of charged particles.

• It is commonly generated by power plants and used for various purposes such as lighting, heating, and powering electronic devices.

• Electricity can be categorized into two types: direct current (DC) and alternating current (AC).

• DC flows in one direction, while AC alternates its direction periodically.

• Voltage, current, and resistance are...read more

Mcb is a miniature circuit breaker used for overcurrent protection, while Rcb is a residual current breaker used for earth fault protection.

• Mcb protects against overcurrents by automatically switching off the circuit when a fault is detected.

• Rcb protects against earth faults by detecting imbalances in the electrical current flowing through the circuit.

• Mcb is commonly used in homes and buildings to protect against short circuits and overloads, while Rcb is used to prevent elec...read more

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

• Current is measured in amperes (A) while voltage is measured in volts (V)

• Current flows from high potential to low potential while voltage is the difference in electric potential between two points

• Ohm's law relates current, voltage, and resistance: I = V/R

• Examples of voltage sources include batteries and power supplies while examples of current sources include generators a...read more

Air Handling Unit

• AHU stands for Air Handling Unit

• AHUs are used to regulate and circulate air as part of HVAC systems

• They typically consist of a blower, heating or cooling elements, filters, and dampers

• AHUs are commonly found in commercial and industrial buildings

There are two main types of motors: AC motors and DC motors.

• AC motors: synchronous and asynchronous

• DC motors: brushed and brushless

• Other types: stepper motors, servo motors, linear motors

• Motors can also be classified by their power source, size, and application

Ohm's law states that the current through a conductor between two points is directly proportional to the voltage across the two points.

• Ohm's law is represented by the equation I = V/R, where I is the current, V is the voltage, and R is the resistance.

• It applies to conductors that are linear and have a constant temperature.

• It is named after Georg Simon Ohm, a German physicist.

• Ohm's law is used extensively in electrical engineering and is fundamental to the design of electrical...read more

Current is the flow of electric charge while voltage is the measure of electric potential difference.

• Current is measured in amperes (A) while voltage is measured in volts (V).

• Current flows from high potential to low potential while voltage is the difference in electric potential between two points.

• Ohm's law relates current, voltage, and resistance: I = V/R.

• Examples of current and voltage include the current flowing through a light bulb and the voltage of a battery.

Transformers are electrical devices that transfer energy between two or more circuits through electromagnetic induction.

• Transformers are used to increase or decrease the voltage of an alternating current (AC) power supply.

• They consist of two coils of wire, known as the primary and secondary coils, which are wrapped around a magnetic core.

• When an AC voltage is applied to the primary coil, it creates a magnetic field that induces a voltage in the secondary coil.

• Transformers are...read more

A motor is an electrical machine that converts electrical energy into mechanical energy.

• Motors are used in various applications such as fans, pumps, compressors, and conveyor systems.

• They work on the principle of electromagnetic induction.

• There are different types of motors such as AC motors, DC motors, stepper motors, and servo motors.

• Motors have a rotor and a stator, and the interaction between the two produces the mechanical energy.

• The speed and torque of a motor can be co...read more

The principle of induction motor is based on the interaction between the magnetic field of the stator and the rotor.

• Induction motor works on the principle of electromagnetic induction

• The stator winding produces a rotating magnetic field

• The rotor winding is short-circuited and the magnetic field induces a current in it, which in turn produces a magnetic field

• The interaction between the two magnetic fields causes the rotor to rotate

• The speed of the rotor is slightly less than t...read more

A cable fault locator is a device used to locate faults in underground cables.

• Cable fault locators use various methods such as time domain reflectometry (TDR) to pinpoint the exact location of a fault.

• They are essential tools for electrical technicians to quickly identify and repair faults in cables.

• Examples of cable fault locators include the Megger EZ-Thump and the Fluke CableIQ Qualification Tester.

Induction motor works on the principle of electromagnetic induction to convert electrical energy into mechanical energy.

• The stator of the motor produces a rotating magnetic field

• The rotor is made up of conductive bars which are short-circuited at both ends

• The rotating magnetic field induces a current in the rotor bars, which in turn produces a magnetic field

• The interaction between the stator and rotor magnetic fields causes the rotor to rotate

• Induction motors are widely used ...read more

A machine is a combination of electrical components that work together to perform a specific function.

• Machines can range from simple devices like a toaster to complex systems like a computer.

• They typically consist of power sources, input/output components, control systems, and mechanical parts.

• Examples include washing machines, refrigerators, and electric motors.

To work a crane, one must be trained in operating the controls, understanding load capacities, and following safety protocols.

• Receive proper training on operating the crane controls

• Understand the load capacities and limitations of the crane

• Follow all safety protocols and guidelines while operating the crane

• Regularly inspect the crane for any maintenance issues

• Communicate effectively with other team members during crane operations