Amara Raja Energy & Mobility Maintenance Electrician Interview Questions and Answers

Maintenance is the process of ensuring that equipment, machinery, and facilities are in good working condition.

• Regular inspection and repair of equipment

• Preventive maintenance to avoid breakdowns

• Replacing worn-out parts

• Cleaning and lubricating machinery

• Ensuring safety standards are met

• Maintaining records of maintenance activities

• Responding to emergency repairs

• Continuous improvement of maintenance processes

PM stands for Preventive Maintenance, MTTR is Mean Time To Repair, and MTBF is Mean Time Between Failures.

• PM is a proactive maintenance strategy that involves regularly scheduled maintenance to prevent equipment failure.

• MTTR is the average time it takes to repair a piece of equipment after a failure.

• MTBF is the average time between equipment failures.

• These metrics are important for measuring the effectiveness of mainte...read more

Power factor is a measure of how effectively electrical power is being used in a circuit.

• Power factor is the ratio of real power (in watts) to apparent power (in volt-amperes).

• It indicates the efficiency of electrical power consumption in a circuit.

• A power factor of 1 means all the power is being used effectively, while a power factor less than 1 indicates wastage of power.

• Inductive loads like motors and transformers h...read more

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

• Motors are used in a variety of applications, from powering industrial machinery to driving household appliances.

• There are different types of motors, including AC motors, DC motors, and stepper motors.

• Motors can be controlled using various methods, such as variable frequency drives and soft starters.

• Proper maintenance and inspection ...read more

A star delta starter is used to reduce the starting current of a motor.

• The motor is initially connected in star configuration to reduce the voltage across each winding.

• After a set time, the motor is switched to delta configuration for normal operation.

• The control diagram includes a timer, contactors, and overload protection.

• The timer delays the switching from star to delta configuration.

• The contactors are used to switc...read more

DOL starter is used in single-phase induction motors and small three-phase motors.

• DOL starter stands for Direct-On-Line starter.

• It is used to start and stop the motor directly without any intermediate control.

• It is commonly used in single-phase induction motors and small three-phase motors.

• DOL starter provides full voltage to the motor during starting, which can cause high starting current.

• It consists of a contactor, t...read more

The resistive load equation is used to calculate the power consumed by a resistive load.

• The equation is P = V^2/R, where P is power, V is voltage, and R is resistance.

• This equation is used in electrical engineering to determine the power consumption of resistive loads such as heaters and incandescent light bulbs.

• The equation can also be rearranged to solve for voltage or resistance, depending on the information given.

• I...read more

Asynchronous motors are used for various purposes due to their simple design and low cost.

• Asynchronous motors are commonly used in industrial applications such as pumps, fans, and compressors.

• They are also used in household appliances like washing machines and refrigerators.

• Asynchronous motors are preferred for their low maintenance and high reliability.

• They are also used in electric vehicles and hybrid cars.

• Asynchrono...read more

Transformers are classified based on their construction, purpose, and voltage level.

• Based on construction: core type, shell type, and Berry type

• Based on purpose: power transformer, distribution transformer, isolation transformer, autotransformer, etc.

• Based on voltage level: step-up transformer, step-down transformer, and isolation transformer

• Other classifications: single-phase transformer, three-phase transformer, and ...read more

India has a total installed capacity of over 370 GW as of 2021.

• India's power generation capacity has been growing rapidly in recent years

• The country has set a target of achieving 450 GW of renewable energy capacity by 2030

• India is one of the world's largest producers of renewable energy, with a capacity of over 100 GW

• Coal still accounts for a significant portion of India's power generation, but the government is workin

Chopper circuits are used to convert a fixed DC voltage to a variable DC voltage.

• Chopper circuits are also known as DC-DC converters.

• They are used in applications such as battery charging, motor control, and renewable energy systems.

• Chopper circuits use high-frequency switching to control the output voltage.

• Examples of chopper circuits include buck converters, boost converters, and buck-boost converters.

A P-V diagram of a double stage air compressor shows the pressure-volume relationship during compression.

• The diagram consists of two stages of compression.

• The first stage compresses the air from atmospheric pressure to an intermediate pressure.

• The second stage compresses the air from the intermediate pressure to the final pressure.

• The volume decreases as the pressure increases during compression.

• The diagram can be used...read more

A strain gauge is a device used to measure strain or deformation in an object.

• It consists of a thin wire or foil that is attached to the object being measured.

• As the object deforms, the wire or foil also deforms, causing a change in its electrical resistance.

• This change in resistance is measured and used to calculate the amount of strain or deformation in the object.

• Strain gauges are commonly used in engineering and ma...read more

Bearings are used to reduce friction between two moving parts. There are different types of bearings.

• Plain bearings

• Rolling element bearings

• Jewel bearings

• Fluid bearings

• Magnetic bearings

Different types of gears include spur gears, helical gears, bevel gears, worm gears, and rack and pinion gears.

• Spur gears have straight teeth and are the simplest and most common type of gear.

• Helical gears have angled teeth and provide smoother and quieter operation compared to spur gears.

• Bevel gears have cone-shaped teeth and are used to transmit power between intersecting shafts.

• Worm gears consist of a worm and a wor...read more

Pumps are selected based on the required flow rate, head, and fluid properties.

• Determine the required flow rate and head for the application

• Consider the fluid properties such as viscosity, temperature, and corrosiveness

• Select a pump type that is suitable for the application, such as centrifugal, positive displacement, or axial flow

• Choose a pump material that is compatible with the fluid being pumped

• Consider the operati...read more

Boilers are classified based on their design, fuel type, and application.

• Fire-tube boilers

• Water-tube boilers

• Electric boilers

• Gas boilers

• Oil boilers

• Solid fuel boilers

• Combination boilers

• Condensing boilers

• Industrial boilers

• Residential boilers

Threads are helical ridges or grooves on the surface of a cylindrical object. There are different types of threads.

• Unified Thread Standard (UTS)

• Metric Thread Standard

• Pipe Thread Standard

• ACME Thread

• Buttress Thread

• Knuckle Thread

• Square Thread

• Round Thread

Valves are devices used to control the flow of fluids or gases. There are several types of valves used in different applications.

• Gate valve

• Ball valve

• Butterfly valve

• Globe valve

• Check valve

• Diaphragm valve

• Needle valve

• Pressure relief valve

• Safety valve

DCV stands for Directional Control Valve in hydraulics which controls the direction of fluid flow.

• DCV is used to control the direction of fluid flow in hydraulic systems.

• It is a type of valve that directs the flow of fluid to different parts of the system.

• DCV can be manually operated or automated depending on the application.

• Examples of DCV include spool valves, poppet valves, and rotary valves.

• DCV is an important comp...read more