40+ Senior Instrument Engineer Interview Questions and Answers

In our plant, we have a wide range of instruments including pressure transmitters, temperature sensors, flow meters, level indicators, control valves, and analyzers.

• Pressure transmitters

• Temperature sensors

• Flow meters

• Level indicators

• Control valves

• Analyzers

The device which generates microwave in radar is called a magnetron.

• Magnetron is a type of vacuum tube that generates microwaves using the interaction of a stream of electrons with a magnetic field.

• It is commonly used in radar systems, microwave ovens, and other electronic devices that require high-frequency electromagnetic waves.

• Examples of radar systems that use magnetrons include weather radar, air traffic control radar, and military radar systems.

The holes in the metal pipe inside the tank for radar gauge are for pressure equalization.

• The holes allow the pressure inside the pipe to equalize with the pressure inside the tank.

• This prevents any false readings due to pressure differences.

• The number and size of the holes are designed based on the tank size and fluid properties.

• The holes also prevent any vacuum formation inside the tank during fluid withdrawal.

• Examples of tanks that use radar gauges with metal pipes and hol...read more

Control valve components, characteristics, and applications

• Control valve components include actuator, positioner, and valve body

• Characteristics include linear, equal percentage, and quick opening

• Linear valves are used for on/off applications, equal percentage for modulating flow, and quick opening for emergency shutdown

• Applications include oil and gas, chemical, and power generation industries

New IOs can be added in existing PLC/DCS system by following these steps:

• Identify the type and number of IOs required

• Check the compatibility of the new IOs with the existing system

• Configure the IOs in the PLC/DCS software

• Install the new IO modules and connect them to the system

• Test the new IOs to ensure proper functioning

Soft tags are assigned in software while hard tags are assigned in hardware.

• Soft tags are used for variables that are not directly connected to hardware.

• Hard tags are used for variables that are directly connected to hardware.

• Soft tags can be assigned through the DCS software.

• Hard tags are assigned through the hardware configuration.

• Examples of soft tags include calculated values and setpoints.

• Examples of hard tags include temperature sensors and valve positions.

Mass flow meter measures the mass flow rate of a fluid in a pipeline.

• Mass flow meter works on the principle of Coriolis effect or thermal dispersion.

• It measures the mass flow rate of a fluid in a pipeline.

• The fluid flows through a vibrating tube and the frequency of vibration is proportional to the mass flow rate.

• It is commonly used in industries such as oil and gas, chemical, and food processing.

• It provides accurate and reliable measurement of fluid flow.

Drum level maintenance differs in 3-element and single element systems.

• In 3-element systems, the drum level is controlled by measuring the water level, steam flow, and feedwater flow.

• In single element systems, only the water level is measured.

• Maintenance in 3-element systems involves checking and calibrating the sensors for each parameter.

• Maintenance in single element systems involves checking and calibrating the water level sensor.

• Regular maintenance is necessary to ensure a...read more

Coriolis mass flowmeter measures mass flow rate by detecting the Coriolis force. Electromagnetic flowmeter measures volumetric flow rate by using Faraday's law of electromagnetic induction.

• Coriolis mass flowmeter measures the mass flow rate directly

• It works on the principle of Coriolis force

• The fluid is forced to oscillate by a vibrating tube and the Coriolis force is measured

• Electromagnetic flowmeter measures the volumetric flow rate

• It works on the principle of Faraday's law...read more

I will ensure smooth start up for plant by conducting thorough testing, creating detailed procedures, and training the operators.

• Conduct thorough testing of all equipment and systems before start up

• Create detailed start up procedures and checklists

• Train operators on the procedures and ensure they understand their roles and responsibilities

• Perform simulations and drills to identify and address any potential issues

• Collaborate with other departments and stakeholders to ensure a ...read more

Emerson transmitters are widely used in industrial instrumentation for measuring and transmitting process variables.

• Emerson transmitters are known for their accuracy, reliability, and advanced features.

• They come in various models, each designed for specific applications and process variables.

• Some popular Emerson transmitter models include Rosemount 3051, 3144, and 644.

• The model number indicates the type of transmitter, its capabilities, and the range of measurements it can ha...read more

Types of valves include gate, globe, ball, butterfly, and check valves. Load cells measure weight, RTDs measure temperature, PTs measure pressure, LTs measure liquid level, FTs measure fluid flow, and TTs measure temperature.

• Valves: gate, globe, ball, butterfly, check

• Load cells: measure weight

• RTDs: measure temperature

• PTs: measure pressure

• LTs: measure liquid level

• FTs: measure fluid flow

• TTs: measure temperature

Yes, I am open to relocating for the Senior Instrument Engineer position.

• I am willing to relocate for the right opportunity.

• I understand that this position may require me to move to a different location.

• I am flexible and adaptable to new environments.

• I have previous experience relocating for work.

• I am excited about the potential opportunities that come with relocation.

Steam drum level transmitter measures the level of water in the steam drum using differential pressure.

• Uses differential pressure to measure the level of water in the steam drum

• Consists of two pressure sensors, one at the bottom and one at the top of the drum

• The difference in pressure between the two sensors is proportional to the level of water in the drum

• Common types include capacitance, ultrasonic, and radar transmitters

Radar level gauge uses electromagnetic waves to measure the level of liquid or solid in a tank or vessel.

• Radar level gauge emits high-frequency electromagnetic waves towards the surface of the liquid or solid in the tank.

• The waves are reflected back to the gauge by the surface of the liquid or solid.

• The time taken for the waves to travel to the surface and back is measured and used to calculate the level of the liquid or solid.

• The gauge can be used for both continuous and poi...read more

Interlocks are safety mechanisms that prevent the turbine from operating under unsafe conditions.

• Interlocks are designed to prevent damage to the turbine and ensure safe operation.

• They can be mechanical, electrical, or software-based.

• Examples include overspeed protection, low oil pressure shutdown, and high exhaust temperature shutdown.

• Interlocks are critical components of turbine control systems and must be properly maintained and tested.

• They are often required by regulatory...read more

Standardizing maintenance procedures involves creating clear guidelines, documentation, and training for consistent and efficient maintenance practices.

• Develop a comprehensive maintenance manual outlining procedures for different equipment and systems

• Implement a system for tracking maintenance activities and scheduling regular inspections

• Provide training to maintenance staff on the standardized procedures and ensure they are followed consistently

• Regularly review and update th...read more

A control valve is a device used to regulate the flow of a fluid in a process system. Loop checking is the process of verifying the functionality of control loops.

• Control valve is used to control the flow rate, pressure, temperature, or level of a fluid in a process system

• Loop checking involves verifying the communication and functionality of control loops in a system

• Loop checking is typically done during commissioning or maintenance of a system

• Examples of loop checking inclu...read more

A VFD gas analyzer system is a system that uses variable frequency drives to control the speed of the gas analyzer pump.

• VFD gas analyzer systems are commonly used in industrial settings to monitor and control gas emissions.

• The system uses a VFD to control the speed of the pump, which in turn controls the flow rate of the gas being analyzed.

• This allows for more accurate and precise measurements of gas concentrations.

• VFD gas analyzer systems can be used for a variety of gases, ...read more

Control valve troubleshooting involves identifying and resolving issues with the valve's performance.

• Check for any leaks or blockages in the valve

• Inspect the valve's positioner and actuator for any faults

• Verify that the valve is receiving the correct signals from the control system

• Check the valve's calibration and adjust if necessary

• Perform a functional test to ensure proper operation

Various instruments and their makes

• Pressure Transmitter - Rosemount, Yokogawa, Honeywell

• Flow Meter - Endress+Hauser, Siemens, Emerson

• Temperature Transmitter - ABB, Siemens, Yokogawa

• Level Transmitter - Vega, Magnetrol, Krohne

Electromagnetic flowmeter measures fluid flow by inducing a magnetic field and measuring the voltage generated by the fluid's movement.

• Uses Faraday's law of electromagnetic induction

• Fluid must be conductive

• No moving parts

• Accurate and reliable

• Commonly used in water treatment, chemical, and food industries

PLC and SCADA DC's installation and commissioning involve setting up and testing the control systems.

• PLC and SCADA systems are installed and configured to control industrial processes.

• DC's (Distributed Control Systems) are used to monitor and control multiple processes from a central location.

• Installation involves mounting hardware, wiring, and configuring software.

• Commissioning involves testing and verifying the system's functionality.

• Examples of industries that use PLC and ...read more

A pressure transmitter hook up diagram shows how to connect the transmitter to the process piping and control system.

• The transmitter should be installed at the point where pressure is to be measured.

• The process piping should be connected to the high and low pressure ports of the transmitter.

• The transmitter should be connected to the control system using appropriate wiring.

• Proper grounding and shielding techniques should be used to prevent electrical interference.

• The hook up d...read more

The number of I/O in the plant is approximately X.

• The exact number of I/O in the plant can vary depending on the size and complexity of the plant.

• I/O stands for input/output and refers to the communication between different devices and systems in the plant.

• The number of I/O can be determined by looking at the plant's control system documentation.

• Some plants may have thousands of I/O points, while others may have only a few hundred.

• Examples of devices that may have I/O include...read more

Emerson DCS programming skills are essential for a Senior Instrumentation Engineer.

• Proficiency in programming languages such as ladder logic, function block, and sequential function chart

• Experience in configuring and programming Emerson DeltaV DCS systems

• Knowledge of Emerson AMS Device Manager software for device configuration and diagnostics

• Ability to troubleshoot and debug DCS programming issues

• Familiarity with industry standards such as ISA-88 and ISA-95

Profibus cables are used for communication between field devices and control systems in industrial automation.

• Profibus cables provide reliable and high-speed communication in industrial environments.

• They are commonly used in process automation, manufacturing, and other industrial applications.

• Profibus cables can support multiple devices on the same network, reducing wiring complexity.

• They are cost-effective and easy to install, making them a popular choice for industrial comm...read more

Control valves regulate the flow of fluids or gases in a process system.

• Control valves have a valve body, actuator, and positioner.

• The valve body contains the flow path and the valve plug.

• The actuator provides the force to move the valve plug.

• The positioner ensures the valve is in the correct position.

• Control valves can be operated manually or automatically.

• Examples of control valves include globe valves, butterfly valves, and ball valves.

The flow transmitter calculation formula is used to determine the flow rate based on the transmitter's output signal.

• The formula typically involves the transmitter's output signal, calibration factor, and engineering units conversion.

• Example: Flow rate (gpm) = Transmitter output (mA) x Calibration factor (gpm/mA)

• Ensure proper units are used in the calculation to obtain accurate results.

Instrumentation is the science and art of measurement and control of process variables within a production or manufacturing setting.

• Instrumentation involves the use of sensors, transmitters, controllers, and final control elements to monitor and regulate process variables such as temperature, pressure, flow, and level.

• It plays a crucial role in ensuring the efficiency, safety, and quality of industrial processes.

• Examples of instrumentation include pressure gauges, temperature...read more

A control valve is a device used to regulate the flow of fluid or gas in a system.

• Control valves are used in various industries such as oil and gas, chemical, and power generation.

• They can be operated manually, electrically, or pneumatically.

• Control valves can be classified into different types such as globe valves, ball valves, and butterfly valves.

• They are essential components in a control loop that helps maintain process variables such as pressure, temperature, and flow ra...read more

Boiler interlock is a safety feature that ensures certain conditions are met before a boiler can operate.

• Boiler interlock prevents the boiler from starting if certain safety conditions are not met.

• Common interlocks include low water level, high pressure, and flame failure.

• Interlocks are crucial for safe and efficient boiler operation.

• Examples of interlocks include pressure switches, temperature sensors, and flame detectors.

TG interlock is a safety feature in a power plant that prevents the turbine generator from starting or operating under unsafe conditions.

• TG interlock stands for Turbine Generator interlock.

• It is a safety feature that ensures the turbine generator does not start or operate if certain conditions are not met.

• Examples of conditions include low oil pressure, high temperature, or overspeed.

• The interlock system may include sensors, alarms, and automatic shutdown mechanisms.

Field instruments are selected based on process requirements, accuracy, reliability, and cost.

• Understand the process requirements and select instruments accordingly

• Consider accuracy and reliability of the instruments

• Evaluate the cost of the instruments and select the most cost-effective option

• Ensure compatibility with the control system

• Consider environmental factors such as temperature and pressure

• Examples of field instruments include pressure transmitters, flow meters, level...read more

BMS system architecture refers to the layout and design of a Building Management System, including its components and how they interact.

• BMS typically consists of sensors, controllers, and actuators to monitor and control building systems such as HVAC, lighting, and security.

• The sensors collect data on various parameters like temperature, humidity, and occupancy, which is then processed by the controllers.

• The controllers make decisions based on the data received and send comma...read more

I&C concepts refer to instrumentation and control systems used in various industries to monitor and control processes.

• I&C systems involve sensors, transmitters, controllers, and final control elements.

• They are used to measure variables such as temperature, pressure, flow, and level.

• Control systems use feedback loops to adjust process variables and maintain desired setpoints.

• Examples include PLCs, DCS, SCADA systems, and control valves.

• I&C engineers design, install, and mainta...read more

Types of level transmitters include ultrasonic, radar, capacitance, and differential pressure.

• Ultrasonic level transmitters use sound waves to measure the distance between the sensor and the liquid surface.

• Radar level transmitters use electromagnetic waves to determine the level of the liquid.

• Capacitance level transmitters measure the change in capacitance between two electrodes as the liquid level changes.

• Differential pressure level transmitters measure the pressure differen...read more

Calibration of instruments ensures accuracy and reliability of measurements.

• Calibration involves comparing the readings of an instrument to a known reference

• Adjustments are made to the instrument to minimize any differences

• Regular calibration is essential to maintain accuracy over time

Flow meters are devices used to measure the flow rate of fluids or gases in a system.

• Differential pressure flow meters (e.g. orifice plate, venturi tube)

• Positive displacement flow meters (e.g. piston, gear, nutating disc)

• Velocity flow meters (e.g. turbine, vortex, electromagnetic)

• Mass flow meters (e.g. Coriolis, thermal, ultrasonic)