Sona Comstar Interview Questions, Process, and Tips

The heat generating component in a motor is the stator winding and rotor core.

• Stator winding and rotor core are the main sources of heat generation in a motor.

• The heat generated is due to the resistance of the winding and core losses.

• Efficient cooling systems are required to dissipate the heat and prevent damage to the motor.

• Examples of cooling systems include air cooling, liquid cooling, and forced ventilation.

Cooling methods for motors include air cooling, liquid cooling, and oil cooling.

• Air cooling involves using a fan to circulate air over the motor to dissipate heat.

• Liquid cooling uses a coolant, such as water or a mixture of water and glycol, to absorb heat from the motor and transfer it to a radiator.

• Oil cooling involves circulating oil through the motor to absorb heat and then transferring it to a heat exchanger.

• The c...read more

A lathe machine is classified based on its size, design, and functionality.

• Classification based on size: mini lathe, bench lathe, engine lathe, turret lathe, etc.

• Classification based on design: horizontal lathe, vertical lathe, center lathe, etc.

• Classification based on functionality: CNC lathe, manual lathe, automatic lathe, etc.

Drive cycle refers to the pattern of vehicle operation over a specified period of time.

• Drive cycle is used to evaluate vehicle emissions and fuel economy.

• It includes different driving modes such as idling, acceleration, deceleration, and cruising.

• Examples of drive cycles include FTP-75, HWFET, and US06.

• Drive cycle data is used to develop and test new vehicle technologies.

• Drive cycles can vary depending on the type of v

The major heating components in an EV motor are the stator winding and the rotor.

• Stator winding: The stator winding is responsible for generating a rotating magnetic field in the motor. It can experience heating due to electrical resistance.

• Rotor: The rotor is the rotating part of the motor and can also generate heat due to friction and electrical resistance.

• Cooling system: EV motors often have a cooling system to diss...read more

Different types of hardness include scratch hardness, indentation hardness, and rebound hardness.

• Scratch hardness is the resistance of a material to scratching or abrasion.

• Indentation hardness is the resistance of a material to permanent deformation caused by a constant load.

• Rebound hardness is the ability of a material to absorb energy and return it upon impact.

• Examples include Mohs scale for scratch hardness, Rockwel...read more

The full form of HRC scale is Rockwell Hardness Scale C.

• HRC stands for Rockwell Hardness Scale C.

• It is a measure of the hardness of a material, commonly used in metallurgy.

• The HRC scale is often used to determine the hardness of steel.

• Higher HRC values indicate harder materials.