Hussmann Electrical Design Engineer Interview Questions and Answers

The percentage of carbon presence in cast iron varies from 2.1% to 6.67% depending on the type of cast iron.

• Cast iron is classified into four types based on its carbon content: white, gray, ductile, and malleable.

• White cast iron has the highest carbon content, ranging from 2.1% to 6.67%.

• Gray cast iron has a lower carbon content, ranging from 2.5% to 4%.

• Ductile cast iron has a carbon content of 3.2% to 4.1%.

• Malleable ca...read more

Addendum is the height of the tooth above the pitch circle in a gear.

• Addendum is the distance between the pitch circle and the top of the gear tooth.

• It is an important parameter in gear design as it affects the strength and durability of the gear.

• The addendum can be calculated using the formula addendum = module or diametral pitch.

• For example, in a gear with a module of 2mm, the addendum would be 2mm.

• Addendum is the op...read more

The least count of vernier calipers is the smallest measurement that can be accurately read on the scale.

• The least count is determined by the number of divisions on the main scale and the vernier scale.

• It is calculated by dividing the smallest division on the main scale by the number of divisions on the vernier scale.

• For example, if the smallest division on the main scale is 0.1 mm and the vernier scale has 10 division

I work for a leading engineering firm specializing in designing and manufacturing industrial machinery.

• We have a team of experienced mechanical engineers who work on various projects

• Our company focuses on innovation and cutting-edge technology in our designs

• We have successfully completed projects for clients in the automotive and aerospace industries

I come from a close-knit family with a strong emphasis on education and hard work.

• My parents are both engineers, so I grew up with a passion for problem-solving and innovation.

• I have two siblings, one of whom is also pursuing a career in engineering.

• Family gatherings often involve discussions about new technologies and projects we are working on.

• My family has always been supportive of my academic and career pursuits.

I am a passionate mechanical engineer with a strong background in designing and implementing innovative solutions.

• Graduated with a degree in Mechanical Engineering from XYZ University

• Completed internships at ABC Company and gained hands-on experience in CAD software

• Led a team project to design and build a prototype for a new cooling system

• Continuously learning and staying updated on the latest industry trends and techn

I am joining this company because of its reputation for innovation and commitment to employee growth.

• Opportunity to work on cutting-edge projects

• Strong focus on professional development

• Positive company culture and values

• Potential for career advancement

• Desire to contribute to a successful team

I have a strong background in mechanical engineering with hands-on experience in designing and implementing innovative solutions.

• Extensive knowledge in mechanical engineering principles and practices

• Proven track record of successfully completing projects on time and within budget

• Strong problem-solving skills and ability to think creatively

• Experience in using CAD software for design and analysis

• Excellent communication a...read more

Composite error and ratio error are two types of errors in current transformers.

• Composite error is the combination of ratio error and phase angle error in a current transformer.

• Ratio error is the difference between the actual turns ratio and the specified turns ratio of a current transformer.

• Phase angle error is the angular difference between the primary and secondary currents of a current transformer.

• Composite error a...read more

An AC drive circuit diagram controls the speed of an AC motor by varying the frequency and voltage of the power supplied to it.

• An AC drive consists of a rectifier, DC link, inverter, and control circuitry.

• The rectifier converts AC power to DC power, which is stored in the DC link.

• The inverter converts the DC power back to AC power with variable frequency and voltage.

• The control circuitry adjusts the frequency and volta...read more

A single line diagram of a distribution system is required with proper specifications.

• The diagram should show the flow of power from the source to the load

• It should include all components such as transformers, switchgear, and cables

• The specifications should include voltage levels, power ratings, and protection devices

• The diagram should follow standard symbols and conventions

• Example: A 11 kV distribution system with a 5

Dewpoint test is done in transformer to check the moisture content in the insulation oil.

• Moisture in insulation oil can cause breakdown of transformer insulation

• Dewpoint test helps to determine the moisture content in the oil

• It is a preventive maintenance measure to avoid transformer failure

• The test involves cooling a mirror until dew forms on it, and measuring the temperature at which dew forms

Power transformers are used in transmission systems to step up or down voltage, while distribution transformers are used in distribution systems to step down voltage.

• Power transformers are used in high voltage transmission systems to step up or down voltage for long distance transmission.

• Distribution transformers are used in low voltage distribution systems to step down voltage for local distribution.

• Power transformers...read more

Buchholz relay is used to protect transformers from faults by detecting gas and oil flow abnormalities.

• Buchholz relay is installed in the pipe connecting the transformer tank and conservator tank.

• It operates based on the principle that faults in the transformer generate gases and cause oil flow disturbances.

• When gas or oil flow abnormalities occur, the relay trips and sends a signal to the control panel to isolate the ...read more

A circuit breaker is an electrical switch that automatically interrupts the flow of current when it exceeds a certain limit.

• It is used to protect electrical circuits from damage caused by overloading or short circuits.

• It works by detecting the excess current and tripping the switch to break the circuit.

• It can be reset manually or automatically depending on the type of circuit breaker.

• Examples include thermal circuit br...read more

A contactor is an electrical switch used for switching an electrical circuit on or off.

• It is used to control electric motors, lighting, heating, and other electrical loads.

• It consists of a coil, contacts, and an enclosure.

• The coil generates a magnetic field that pulls the contacts together to close the circuit.

• Examples include HVAC systems, elevators, and industrial machinery.

• Contactor ratings are based on the amount o...read more

MCB stands for Miniature Circuit Breaker. It is an electrical switch that automatically shuts off the electrical circuit during an overload or short circuit.

• MCB is a type of circuit breaker that is commonly used in residential and commercial buildings.

• It is designed to protect electrical circuits from damage caused by overloading or short circuits.

• MCBs are available in different current ratings and can be easily replac...read more

A motor is a device that converts electrical energy into mechanical energy to produce motion.

• Motors are used in various applications such as electric vehicles, industrial machinery, and household appliances.

• There are different types of motors such as DC motors, AC motors, stepper motors, and servo motors.

• The basic principle of a motor is the interaction between a magnetic field and an electric current.

• Examples of motor...read more

A current transformer is a device that measures the current flowing in a circuit by producing a proportional current in its secondary winding.

• Consists of a primary winding and a secondary winding

• Primary winding is connected in series with the circuit carrying the current to be measured

• Secondary winding is connected to a measuring instrument or protective relay

• Produces a current in the secondary winding that is proporti...read more

Measuring equipment used in mechanical engineering.

• Calipers for measuring distance between two opposite sides of an object

• Micrometers for measuring small distances

• Dial indicators for measuring small distances and angles

• Gauge blocks for calibrating measuring equipment

• Height gauges for measuring vertical distances

• Surface plates for measuring flatness and parallelism

• Coordinate measuring machines for precise measurements i