Head of Department Electrical Interview Questions and Answers

Different types of loads include resistive, inductive, and capacitive loads. Motor selection depends on factors like load type, power requirements, speed, and efficiency.

• Resistive loads convert electrical energy into heat, like incandescent light bulbs.

• Inductive loads create magnetic fields, like motors and transformers.

• Capacitive loads store electrical energy, like capacitors.

• Select motor based on load type, power requirements, speed, and efficiency.

• Consider factors like sta...read more

DGA test is a significant diagnostic tool used to analyze the dissolved gases in transformer oil to detect potential faults.

• DGA test helps in identifying potential faults in transformers by analyzing the presence of specific gases such as methane, ethylene, and acetylene.

• The levels of these gases can indicate issues like overheating, partial discharge, or arcing within the transformer.

• Interpretation of DGA results requires knowledge of typical gas ratios and trends associated...read more

Interlocks in the chiller are safety mechanisms that prevent the chiller from operating under unsafe conditions.

• Interlocks can include high pressure, low pressure, and temperature sensors that shut down the chiller if thresholds are exceeded.

• Interlocks may also include flow switches to ensure proper flow of refrigerant or water through the chiller.

• Some chillers have interlocks that prevent the compressor from starting if the oil level is too low.

• Interlocks are essential for p...read more

gd2 is a measure of the inertia of a rotating body, calculated as the product of the mass moment of inertia and the square of the angular velocity.

• gd2 is used in engineering to analyze the rotational motion of objects.

• It is calculated by multiplying the mass moment of inertia by the square of the angular velocity.

• gd2 is important in designing rotating machinery and systems.

• For example, in the design of a flywheel for energy storage, gd2 is a critical parameter.