40+ Testing & Commissioning Engineer Interview Questions and Answers

Tan delta test is used to measure insulation quality of transformer. GST and GSTg modes differ in the type of voltage applied.

• Tan delta test measures the power loss in transformer insulation.

• It helps to identify the presence of moisture, oil, or other contaminants in the insulation.

• GST mode applies AC voltage to the transformer while GSTg mode applies DC voltage.

• GSTg mode is more sensitive to insulation defects than GST mode.

• The test is important for ensuring the reliability ...read more

An Electrical Engineer is a professional who designs, develops, and maintains electrical systems and equipment.

• Electrical engineers work on various projects such as power generation, transmission, and distribution systems.

• They design and analyze electrical circuits and systems to ensure their efficiency and safety.

• They may specialize in areas such as power electronics, control systems, or telecommunications.

• Electrical engineers often collaborate with other professionals, such...read more

The first step would be to investigate the cause of the secondary core of ct being open while the feeder is still working on very less load.

• Check for any loose connections in the secondary core of ct

• Inspect for any damage or faults in the secondary core of ct

• Verify the load on the feeder to ensure it is within normal operating range

• Consult with colleagues or experts for further troubleshooting steps

SFRA stands for Sweep Frequency Response Analysis. It is a test used to analyze the frequency response of transformers.

• SFRA is a non-invasive test used to detect winding deformation, core movement, and other mechanical issues in transformers.

• The test involves sweeping a frequency range and measuring the response of the transformer.

• The results are plotted on a graph, which can be used to identify any abnormalities in the transformer's frequency response.

• The graph is read by an...read more

LIBBP and HIBBP stability and sensitivity refer to protection schemes for electrical systems. Implementing logic for one incomer and three outgoing feeders involves setting up coordination and communication between devices. BBP protection testing ensures the system operates correctly under fault conditions.

• LIBBP and HIBBP stability and sensitivity are important for ensuring reliable protection of electrical systems.

• Implementing logic for one incomer and three outgoing feeders...read more

Close block is a device used to short circuit the secondary of a current transformer (CT) during testing to prevent damage to the CT. No fuse or MCB is used on the CT circuit to avoid any interruption during testing.

• Close block is used to short circuit the secondary of a CT during testing to prevent damage.

• It ensures that the CT is not overloaded with excessive current during testing.

• No fuse or MCB is used on the CT circuit during testing to avoid any interruption in the curr...read more

Yes, as a Testing & Commissioning Engineer, I am aware of the works being done on site by an electrical engineer.

• As a Testing & Commissioning Engineer, I am responsible for ensuring that electrical systems are installed correctly and functioning properly.

• I work closely with electrical engineers to test and commission various electrical systems, such as power distribution, lighting, and control systems.

• I am familiar with the design, installation, and operation of electrical sy...read more

It depends on various factors such as location, cost, efficiency, and environmental impact.

• Solar energy is renewable and environmentally friendly, but it can be intermittent depending on weather conditions.

• Thermal energy production can be more reliable and consistent, but it may have higher initial costs and environmental impacts.

• The choice between solar and thermal energy production should be based on specific project requirements and goals.

• Factors to consider include locati...read more

I have 5 years of experience in substation network.

• I have worked on various substation projects, including design, testing, and commissioning.

• I have experience with different types of substation equipment and systems.

• I have successfully completed multiple substation network projects on time and within budget.

The relay types used in Indian railways include electro-mechanical relays, solid-state relays, and microprocessor-based relays.

• Electro-mechanical relays are commonly used in Indian railways for various applications.

• Solid-state relays are used for their reliability and faster response times.

• Microprocessor-based relays are used for advanced protection and control functions.

• Examples of relay types used in Indian railways include the Westinghouse Type 'K' relay and the ABB RET670...read more

Swapping two numbers without using inbuilt functions can be achieved using arithmetic operations.

• Create a temporary variable to store one of the numbers.

• Assign the value of the first number to the second number.

• Assign the value of the temporary variable to the first number.

Electrical engineering deals with the generation, transmission, and distribution of electrical power, while electronics engineering focuses on electronic devices and circuits.

• Electrical engineering primarily deals with large-scale power generation, transmission, and distribution systems.

• Electronics engineering focuses on small-scale electronic devices, circuits, and systems.

• Electrical engineering involves working with power generation plants, substations, and power lines.

• Elec...read more

Protection devices are devices used to protect electrical systems from faults and overloads.

• Overcurrent relays

• Differential relays

• Distance relays

• Earth fault relays

• Under voltage relays

alfanar Saudi Arabia is a leading electrical engineering company in the Middle East.

• alfanar Saudi Arabia specializes in electrical engineering solutions.

• They offer a wide range of products and services including power distribution, control panels, and lighting solutions.

• The company has a strong presence in the Middle East and has completed numerous projects in the region.

• alfanar Saudi Arabia is known for its quality and reliability in the field of electrical engineering.

Dispatch signals are signals sent to initiate a specific action or task, while receiving signals are signals received to acknowledge or respond to a dispatched signal.

• Dispatch signals are used to trigger a process or task.

• Receiving signals are used to acknowledge or respond to a dispatched signal.

• Dispatch signals can be in the form of electrical, digital, or wireless signals.

• Receiving signals can be in the form of confirmation messages, acknowledgments, or feedback.

• Dispatch s...read more

I am a Testing & Commissioning Engineer with experience in various industries.

• I have a degree in Electrical Engineering

• I have worked on projects in the power generation industry

• I have experience in testing and commissioning of electrical systems

• I am familiar with various testing equipment and software

• I have worked on projects in the oil and gas industry

Access control system, Fire alarm system, HVAC, VESDA are all essential components of building infrastructure.

• Access control system: regulates who can enter or exit a building or specific areas within a building.

• Fire alarm system: detects and alerts occupants of a building in case of fire or smoke.

• HVAC (Heating, Ventilation, and Air Conditioning): controls the temperature, humidity, and air quality within a building.

• VESDA (Very Early Smoke Detection Apparatus): provides early...read more

Relays and timers are electrical devices used to control the flow of electricity in a circuit. They work by opening or closing contacts based on specific conditions.

• Relays are electromechanical devices that use an electromagnet to open or close electrical contacts. They are used to control high voltage circuits with low voltage signals.

• Timers are devices that control the timing of events in a circuit. They can be digital or analog and are used to delay or sequence actions.

• Int...read more

The scope of work in a chiller plant includes installation, maintenance, troubleshooting, and optimization of chiller systems.

• Installation of chiller units and associated equipment

• Regular maintenance to ensure optimal performance

• Troubleshooting issues such as leaks, malfunctions, or inefficiencies

• Optimizing chiller plant operations for energy efficiency

• Ensuring compliance with safety and environmental regulations

• Monitoring and controlling chiller plant parameters

• Training staf...read more

Various types of electrical equipment include transformers, generators, circuit breakers, relays, and switchgear.

• Transformers

• Generators

• Circuit breakers

• Relays

• Switchgear

Real power is the actual power consumed by a circuit, while apparent power is the combination of real power and reactive power.

• Real power is the power actually consumed by a circuit to perform work.

• Apparent power is the combination of real power and reactive power in a circuit.

• Real power is measured in watts (W), while apparent power is measured in volt-amperes (VA).

• The relationship between real power, apparent power, and power factor is given by the equation: Real Power = Ap...read more

Yes, I am willing and able to go to remote locations for testing and commissioning work.

• I have experience working in remote locations and am comfortable with the challenges that come with it.

• I am willing to travel and stay on site for extended periods of time if necessary.

• I understand the importance of thorough testing and commissioning and am committed to ensuring that the work is done properly, regardless of location.

• I am familiar with the necessary safety protocols and pro...read more

E-mobility refers to the use of electric vehicles and related infrastructure for transportation.

• E-mobility is a growing trend in the automotive industry.

• It involves the use of electric vehicles (EVs) powered by batteries or fuel cells.

• E-mobility aims to reduce carbon emissions and dependence on fossil fuels.

• It requires the development of charging infrastructure, such as charging stations.

• E-mobility also includes the integration of renewable energy sources for charging EVs.

• Exa...read more

The principles of testing involve thorough planning, clear objectives, systematic approach, documentation, and validation.

• Thorough planning is essential to identify test objectives, scope, resources, and timelines.

• Clear objectives help in defining what needs to be tested and the expected outcomes.

• A systematic approach ensures that tests are conducted in a structured manner to achieve reliable results.

• Documentation of test plans, procedures, and results is crucial for traceabi...read more

Electronics manufacturers card assembly for card

• The question is asking about the process of assembling electronic cards

• The focus is on the manufacturing aspect of electronics

• The term 'card' refers to a specific electronic component or circuit board

• The answer should provide details about the steps involved in card assembly

• Examples of card assembly processes may include soldering components, testing functionality, and quality control

Improving knowledge requires continuous learning and seeking new experiences.

• Read books and articles on relevant topics

• Attend workshops, seminars, and conferences

• Take online courses and tutorials

• Join professional organizations and networking groups

• Seek mentorship and guidance from experienced professionals

• Engage in hands-on learning and experimentation

• Reflect on past experiences and learn from mistakes

• Stay up-to-date with industry trends and advancements

Logic gates are fundamental building blocks of digital circuits that perform logical operations based on input signals.

• Logic gates include AND, OR, NOT, NAND, NOR, XOR, and XNOR gates.

• Truth table shows the output of a logic gate for all possible input combinations.

• Example: Truth table for an AND gate - Input A, Input B, Output; 0, 0, 0; 0, 1, 0; 1, 0, 0; 1, 1, 1.

Transformers are used to change the voltage of electricity for transmission and distribution purposes.

• Step up or step down voltage levels for transmission and distribution

• Isolate electrical circuits

• Reduce energy losses during transmission

• Examples: power distribution, electrical substations

Circuit breaker is used to protect electrical circuits from damage caused by overload or short circuit, while isolator is used to isolate a circuit for maintenance or repair.

• Circuit breaker is designed to automatically open and close the circuit in case of overload or short circuit.

• Isolator is manually operated to disconnect a circuit for maintenance or repair.

• Circuit breaker is a safety device, while isolator is a switching device.

• Examples: MCB (Miniature Circuit Breaker) is...read more

A transformer is a device that transfers electrical energy between two or more circuits through electromagnetic induction.

• Consists of two or more coils of insulated wire wrapped around a core

• Primary coil receives electrical energy and induces a magnetic field in the core

• Secondary coil receives the magnetic field and converts it back into electrical energy

• Used to step up or step down voltage levels in power distribution systems

Various sources of energy production include fossil fuels, renewable energy, nuclear power, and hydroelectric power.

• Fossil fuels such as coal, oil, and natural gas are commonly used for energy production.

• Renewable energy sources like solar, wind, and geothermal power are becoming increasingly popular.

• Nuclear power plants generate electricity through nuclear reactions.

• Hydroelectric power is generated by harnessing the energy of flowing water in dams.

• Other sources include bioma...read more

An induction motor is a type of AC motor where power is supplied to the rotor by electromagnetic induction.

• Induction motors are commonly used in various industrial applications due to their simplicity and reliability.

• They do not require any brushes or commutators for operation.

• The speed of an induction motor is determined by the frequency of the AC power supply and the number of poles in the motor.

• Examples of induction motors include squirrel cage motors and wound rotor motor...read more

A substation is a facility used for transforming voltage levels and distributing electricity to consumers.

• A substation is a part of an electrical generation, transmission, and distribution system.

• It is used to transform voltage levels from high to low or vice versa for efficient power distribution.

• Substations may also include circuit breakers, transformers, and other equipment to control and protect the electrical system.

• Examples of substations include step-up substations nea...read more

AC stands for alternating current, which periodically changes direction, while DC stands for direct current, which flows in one direction.

• AC is commonly used in household appliances and power distribution systems.

• DC is commonly used in batteries and electronic devices.

• AC voltage changes direction periodically, while DC voltage flows in one direction continuously.

• AC is easier to transform between voltage levels using transformers, while DC requires electronic converters for vo...read more

The unit of power is watt (W).

• The unit of power is measured in watts (W).

• Power is the rate at which work is done or energy is transferred.

• 1 watt is equal to 1 joule per second.

• Common examples of power units include kilowatts (kW) and megawatts (MW).

Ohm's law states that the current flowing through a conductor is directly proportional to the voltage applied across it, and inversely proportional to the resistance of the conductor.

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

• It helps in calculating the current, voltage, or resistance in a circuit when the other two values are known.

• For example, if a circuit has a voltage of 12V and a resistance of 4 ohms, the curr...read more

Sampling theorem states that a continuous signal can be perfectly reconstructed from its samples if the sampling rate is greater than twice the highest frequency component of the signal.

• Sampling theorem, also known as Nyquist-Shannon theorem, is essential in digital signal processing.

• It states that in order to accurately reconstruct a continuous signal from its samples, the sampling rate must be at least twice the highest frequency component of the signal.

• If the sampling rate...read more

Impedance is the measure of opposition to the flow of alternating current in a circuit.

• Impedance is a combination of resistance and reactance in a circuit.

• It is measured in ohms (Ω).

• Impedance can be calculated using the formula Z = √(R^2 + X^2), where R is resistance and X is reactance.

• Impedance is important in determining the behavior of circuits in AC systems.

• Examples of components with impedance include resistors, capacitors, and inductors.

A DOL starter, or Direct-On-Line starter, is an electrical device used to start motors by applying full line voltage to the motor terminals.

• DOL starters provide a simple and cost-effective method of starting motors.

• They consist of a contactor, overload relay, and start and stop push buttons.

• When the start button is pressed, the contactor closes and applies full voltage to the motor.

• The overload relay protects the motor from overheating by tripping if the current exceeds a set...read more

Testing of HT LT panel involves various procedures to ensure its functionality and safety.

• Testing of HT LT panel includes visual inspection for any physical damage or loose connections.

• Functional testing is performed to check the operation of various components such as circuit breakers, relays, meters, etc.

• Insulation resistance testing is conducted to verify the insulation integrity of the panel.

• High voltage testing is carried out to assess the panel's ability to withstand hi...read more

KCL and KVL are fundamental laws in electrical engineering used to analyze circuits.

• KCL (Kirchhoff's Current Law) states that the total current entering a node is equal to the total current leaving the node.

• KVL (Kirchhoff's Voltage Law) states that the sum of voltages around a closed loop in a circuit is zero.

• KCL is based on the principle of conservation of charge, while KVL is based on the principle of conservation of energy.

• KCL is used to analyze current flow in a circuit, ...read more