Steag Energy Services Interview Questions, Process, and Tips

Onan and ONAF are two cooling methods used in transformers.

• ONAN stands for Oil Natural Air Natural, while ONAF stands for Oil Natural Air Forced.

• ONAN is a self-cooling method where the transformer is cooled by natural convection of oil and air, while ONAF uses fans to force air over the transformer.

• ONAF is more efficient than ONAN, but also more expensive.

• ONAF is used in transformers where the ONAN method is not suffic...read more

PRV is used in transformers to regulate the voltage and protect the equipment from overvoltage.

• PRV stands for Pressure Relief Valve.

• It regulates the voltage and maintains it within safe limits.

• It protects the transformer from overvoltage and prevents damage to the equipment.

• PRV is installed on the transformer tank and is designed to release excess pressure in case of an overvoltage event.

• It is a safety feature that ens...read more

Transformer simulation test is conducted to ensure the proper functioning of the transformer under different conditions.

• To verify the transformer's ability to withstand overloads and short circuits

• To determine the transformer's efficiency and voltage regulation

• To identify any potential issues with the transformer's insulation or winding

• To ensure the transformer meets industry standards and specifications

• Examples of tes...read more

Dominant frequencies of 1×, 2×, and 3× RPM in the spectrum indicate faults in rotating equipment.

• 1× RPM indicates misalignment or unbalance

• 2× RPM indicates gear or bearing faults

• 3× RPM indicates resonance or coupling issues

Diagnosing abnormal sound from mill motor without vibration analyzer

• Check for any visible signs of damage or wear on the motor and surrounding components

• Listen for any changes in the sound when the motor is turned off and on again

• Check the lubrication system and oil levels

• Inspect the belts and pulleys for any signs of wear or damage

• Consult with experts or manufacturers for further guidance

Centrifugal pump performance characteristics refer to the relationship between flow rate, head, power, and efficiency.

• Flow rate is the volume of fluid that passes through the pump per unit time.

• Head is the energy added to the fluid by the pump and is proportional to the pressure increase.

• Power is the energy required to operate the pump and is proportional to the flow rate and head.

• Efficiency is the ratio of the energy ...read more

HP and KW are units of power measurement, with HP being the imperial unit and KW being the metric unit.

• HP stands for horsepower and is commonly used in the United States and other countries that use the imperial system of measurement.

• KW stands for kilowatt and is commonly used in countries that use the metric system of measurement.

• 1 horsepower is equal to 0.7457 kilowatts.

• The relationship between HP and KW is important...read more