Sona Comstar Maintenance Engineer Interview Questions and Answers

There are several types of valves in instrumentation.

• Gate valve

• Ball valve

• Butterfly valve

• Globe valve

• Check valve

• Diaphragm valve

• Needle valve

• Plug valve

• Pressure relief valve

• Safety valve

PT, LT and LVDT are types of sensors used in engineering for measuring pressure, temperature and displacement respectively.

• PT stands for Pressure Transducer and is used to measure pressure in various applications such as hydraulic systems, engines, and pipelines.

• LT stands for Linear Transducer and is used to measure temperature in various applications such as engines, HVAC systems, and industrial processes.

• LVDT stands ...read more

Calibration of I/P converter involves adjusting the output pressure to match the input signal.

• Connect the I/P converter to a pressure source and a signal generator

• Adjust the input signal to the desired value

• Measure the output pressure and adjust it to match the input signal

• Repeat the process at different input signal levels to ensure accuracy

• Document the calibration results for future reference

A load cell is a transducer that converts force into an electrical signal. Calibration involves applying known loads and adjusting the output signal.

• Load cell measures force or weight

• It converts the force into an electrical signal

• Calibration involves applying known loads and adjusting the output signal

• Calibration can be done using a calibration machine or weights

• Calibration should be done regularly to ensure accurate r

The types of lacquer used on lens and housing include acrylic lacquer, polyurethane lacquer, and epoxy lacquer.

• Acrylic lacquer is commonly used on lens and housing due to its high transparency and UV resistance.

• Polyurethane lacquer provides excellent durability and chemical resistance, making it suitable for lens and housing.

• Epoxy lacquer offers superior adhesion and impact resistance, making it a preferred choice for

A size fine filter is a type of filter used to remove small particles or impurities from a fluid or gas.

• Size fine filters are commonly used in industries such as manufacturing, pharmaceuticals, and food processing.

• They are designed to capture particles that are smaller than what can be filtered by regular filters.

• These filters can be made of various materials such as paper, fabric, or synthetic fibers.

• Examples of size ...read more

Direct metalizing is applicable on materials that can conduct electricity.

• Direct metalizing is a process of coating a non-metallic surface with a thin layer of metal.

• The material should be able to conduct electricity for direct metalizing to be applicable.

• Materials like plastic, glass, and ceramics can be direct metalized.

• Direct metalizing is commonly used in the automotive, aerospace, and electronics industries.

The amount of UV energy required for curing depends on the type of material being cured and the intensity of the UV light.

• UV energy required for curing varies depending on the material being cured

• Intensity of the UV light also affects the amount of energy required

• UV energy is typically measured in Joules per square centimeter (J/cm²)

• Examples of materials that require UV curing include adhesives, coatings, and inks

The amount of DFT required as per standard varies depending on the specific industry and project requirements.

• The required amount of DFT (Design for Testability) is determined by industry standards and project specifications.

• Different industries may have different standards for DFT.

• The complexity and size of the project also influence the amount of DFT required.

• DFT techniques include scan chains, built-in self-test (BI...read more