NTPC Interview Questions and Answers

Theory of machine is a branch of engineering that deals with the study of machines and their mechanisms.

• Theory of machine focuses on understanding the principles behind the operation of machines.

• It involves studying the design, construction, and operation of machines.

• Examples include studying the movement of gears in a gearbox or the operation of a piston in an engine.

PA fan stands for Primary Air fan, which is used in power plants to supply air for combustion in the boiler.

• Supplies primary air for combustion in the boiler

• Helps in maintaining proper air-fuel ratio for efficient combustion

• Assists in controlling the temperature and pressure inside the boiler

• Improves the overall efficiency of the boiler

• Examples: FD fan in a power plant

ID fan is used to control the draft in the furnace while PA fan is used to supply combustion air to the furnace.

• ID fan is located at the outlet of the furnace while PA fan is located at the inlet of the furnace.

• ID fan helps in maintaining negative pressure inside the furnace while PA fan helps in supplying air for combustion.

• ID fan is used to extract flue gases from the furnace while PA fan is used to supply primary an...read more

I admire this company's commitment to innovation and its strong values, which align with my professional goals and personal beliefs.

• The company's reputation for innovation in the industry, such as its recent product launch that revolutionized patient care.

• Alignment with the company's core values, particularly its focus on sustainability and community engagement, which resonates with my personal beliefs.

• Opportunities fo...read more

I believe my skills and values align well with your company's mission and culture, fostering collaboration and innovation.

• Strong alignment with company values: I resonate with your commitment to integrity and excellence, as demonstrated in my previous role where I led a team to achieve a 20% increase in customer satisfaction.

• Proven leadership experience: In my last position, I managed a diverse team, promoting a cultur...read more

Heat exchangers are devices used to transfer heat between two or more fluids, without mixing them together.

• Shell and tube heat exchanger

• Plate heat exchanger

• Double pipe heat exchanger

• Finned tube heat exchanger

• Spiral heat exchanger

Preeming is called grooming in the fire service.

• Preeming is the act of cleaning and maintaining equipment in the fire service.

• Grooming ensures that all equipment is in proper working order and ready for use during emergencies.

• Examples of grooming tasks include cleaning and inspecting hoses, nozzles, and other firefighting gear.

Different types of hydrants include wet barrel hydrants, dry barrel hydrants, and post hydrants.

• Wet barrel hydrants are commonly used in warmer climates and have the valve at the top of the hydrant.

• Dry barrel hydrants are typically used in colder climates and have the valve at the bottom of the hydrant to prevent freezing.

• Post hydrants are mounted on a post above ground level and are often used in rural areas or parks.

Different types of couplings include rigid, flexible, sleeve, and clamp couplings.

• Rigid couplings do not allow for any misalignment between shafts

• Flexible couplings can accommodate slight misalignments and vibrations

• Sleeve couplings are simple and inexpensive, but not suitable for high torque applications

• Clamp couplings use screws or clamps to secure the connection between shafts

Different types of hoses used in firefighting include attack hoses, supply hoses, and booster hoses.

• Attack hoses are used to deliver water or foam to extinguish fires.

• Supply hoses are used to bring water from a water source to the fire scene.

• Booster hoses are smaller in diameter and used for small fires or for mop-up operations.

AC, or alternating current, is an electric current that reverses direction periodically, commonly used in power systems.

• AC voltage varies sinusoidally over time, typically represented as a sine wave.

• Commonly used in household power supply, e.g., 120V or 240V AC.

• AC is more efficient for long-distance power transmission compared to DC.

• Transformers can easily step up or step down AC voltage levels.

• Examples of AC sources i...read more

A motor is a device that converts electrical energy into mechanical energy to perform work.

• Types of motors include AC motors, DC motors, and stepper motors.

• AC motors are commonly used in household appliances like fans and refrigerators.

• DC motors are often found in toys and small gadgets due to their simplicity.

• Stepper motors are used in precision applications like 3D printers and CNC machines.

• Motors operate based on el...read more

A relay is an electromechanical switch that opens or closes circuits based on an electrical signal.

• Relays are used to control high voltage devices with low voltage signals.

• Common applications include automotive systems, home appliances, and industrial machinery.

• A typical relay consists of an electromagnet, armature, and contacts.

• For example, a relay can turn on a motor when a button is pressed.

• Relays can be found in sa...read more

A transformer is an electrical device that transfers electrical energy between circuits through electromagnetic induction.

• Transformers are used to increase (step-up) or decrease (step-down) voltage levels.

• Commonly found in power distribution systems to manage voltage levels.

• Example: A step-down transformer reduces high voltage from power lines to a safer level for homes.

• They consist of primary and secondary coils wound...read more

Switchgear refers to electrical devices that control, protect, and isolate electrical equipment in power systems.

• Switchgear includes circuit breakers, fuses, and disconnect switches.

• It is used in substations, industrial plants, and commercial buildings.

• Examples include air-insulated switchgear (AIS) and gas-insulated switchgear (GIS).

• Switchgear ensures safety by interrupting fault currents and isolating faulty equipmen...read more

Store management involves overseeing daily operations, staff management, inventory control, and customer service.

• Daily operations include opening and closing procedures, ensuring cleanliness and organization, and monitoring sales.

• Staff management involves hiring, training, scheduling, and performance evaluations.

• Inventory control includes ordering products, managing stock levels, and conducting regular audits.

• Customer ...read more