10+ VaanTech IT Solutions & Services Interview Questions and Answers

A slipring induction motor is a type of AC motor that uses slip rings to transfer power to the rotor.

• Consists of a stator and a rotor

• Uses slip rings to transfer power to the rotor

• Commonly used in applications where variable speed is required

• Examples include cranes, elevators, and conveyor systems

Corona effect is the ionization of air surrounding a conductor due to high voltage gradient.

• Occurs in high voltage transmission lines

• Leads to power loss and radio interference

• Can be reduced by increasing conductor diameter or using bundled conductors

• Can also be reduced by using corona rings or grading rings

• Can be dangerous for people and animals in close proximity

Dol starter is an electrical device used to start and stop motors.

• Dol stands for Direct-On-Line.

• It is used for motors with low to medium power ratings.

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

• When the start button is pressed, the contactor closes and the motor starts.

• When the stop button is pressed, the contactor opens and the motor stops.

My favourite subject is Mathematics.

• I enjoy solving complex problems and equations.

• I find it fascinating how mathematical concepts can be applied in various fields.

• I have excelled in mathematics throughout my academic career.

• I particularly enjoy calculus and statistics.

• Mathematics is a fundamental subject that forms the basis of many other subjects.

Different types of mixes in the field include concrete, mortar, and grout. Types of cement manufactured include Portland cement, white cement, and blended cement. Volumetric mix design ratios vary depending on the specific application.

• Types of mixes in the field: concrete, mortar, grout

• Types of cement manufactured: Portland cement, white cement, blended cement

• Volumetric mix design ratios depend on the specific application

OPC and PPC cement have different IS codes.

• OPC cement has IS code 269:1989 while PPC cement has IS code 1489:1991.

• OPC cement is made by grinding clinker with gypsum while PPC cement is made by adding pozzolanic material like fly ash to clinker.

• OPC cement has higher strength and is used for construction of high-rise buildings while PPC cement is used for mass concrete works like dams and bridges.

Concrete mix design involves determining the proportions of ingredients to achieve desired properties.

• Determine the required strength and durability of the concrete

• Select suitable materials such as cement, aggregates, and water

• Calculate the proportions of each material based on desired properties

• Perform trial mixes and tests to optimize the mix design

• Adjust the mix design as needed to meet specifications

Common issues in concrete structures include cracking, spalling, and corrosion.

• Cracking due to shrinkage, thermal expansion, or overloading

• Spalling caused by freeze-thaw cycles, chemical exposure, or poor curing

• Corrosion of reinforcing steel due to exposure to moisture and chloride ions

• Joint failure due to inadequate design or construction

• Alkali-silica reaction causing expansion and cracking

• Carbonation leading to loss of alkalinity and reduced protection against corrosion

• Abra...read more

Process control is the use of technology to monitor and control industrial processes.

• Process control involves measuring variables such as temperature, pressure, and flow rate.

• Control systems use this data to adjust process parameters and maintain optimal conditions.

• Examples include controlling the temperature in a chemical reactor or the flow rate of water in a pipeline.

• Process control is essential for ensuring product quality, reducing waste, and improving efficiency.

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A strain gauge is a device used to measure the strain or deformation of an object by detecting changes in electrical resistance.

• Strain gauges are often used in engineering applications to monitor the structural integrity of buildings, bridges, and machinery.

• They work on the principle that the electrical resistance of a wire changes when it is stretched or compressed.

• The amount of strain on an object can be calculated by measuring the change in resistance of the strain gauge.

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Speed sensors are devices used to measure the speed of an object or system.

• Hall effect sensor

• Inductive sensor

• Optical sensor

• Magnetic sensor

• Doppler sensor