Kent plc Electrical Commissioning Technician Interview Questions and Answers for Experienced

An electrical system is a network of interconnected components that work together to generate, transmit, and distribute electrical power.

• An electrical system includes power generation sources such as power plants or renewable energy sources.

• It also includes transmission lines that carry electricity over long distances.

• Distribution networks deliver electricity to homes, businesses, and other end-users.

• Electrical systems...read more

Star-Delta starter is used to start 3-phase motors. It reduces the starting current and torque.

• Star-Delta starter connects the motor in star configuration during starting to reduce the starting current and torque.

• After a few seconds, the starter switches the motor to delta configuration for normal operation.

• This method is used for motors with high starting current and torque requirements.

• It is commonly used in industri...read more

DOL starter is a direct-on-line starter used to start 3-phase motors by connecting them directly to the power supply.

• DOL starter provides full voltage to the motor at the start

• It consists of a contactor, overload relay, and start/stop push buttons

• The contactor connects the motor to the power supply

• The overload relay protects the motor from overloading

• The start/stop push buttons control the on/off function of the motor

LEL and UEL of natural gas indicate the flammability range, crucial for safety in handling and usage.

• LEL (Lower Explosive Limit) of natural gas is approximately 5% by volume in air.

• UEL (Upper Explosive Limit) of natural gas is about 15% by volume in air.

• Concentration below LEL means the mixture is too lean to ignite.

• Concentration above UEL means the mixture is too rich to ignite.

• Example: A natural gas leak with 6% conc

Process safety focuses on preventing industrial accidents, while personal safety emphasizes individual protection from harm.

• Process safety involves managing risks associated with industrial processes, such as chemical reactions.

• Personal safety is concerned with protecting individuals from accidents and injuries in the workplace.

• Example of process safety: Implementing safety protocols in a chemical plant to prevent expl...read more

Flash point is the lowest temperature at which vapors ignite; fire point is the temperature at which sustained combustion occurs.

• Flash point is crucial for assessing flammability of liquids.

• Fire point is typically a few degrees higher than the flash point.

• Example: Gasoline has a flash point of around -45°C, while its fire point is about -40°C.

• Used in safety regulations and material handling guidelines.