Om Electrical Instrument Engineer Interview Questions and Answers

Automation is the use of technology to control and monitor processes, reducing human intervention.

• Automation involves the use of control systems to operate equipment and machinery.

• It aims to increase efficiency, productivity, and safety by minimizing human error.

• Examples include automated manufacturing processes, smart home systems, and self-driving cars.

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

• Instrumentation involves the use of sensors, transmitters, controllers, and final control elements to monitor and control processes.

• Examples of instrumentation include pressure gauges, temperature sensors, flow meters, and control valves.

• Instrumentation plays a crucial role in ensuring the ef...read more

PLCs are used for automation of industrial processes, such as controlling machinery and equipment.

• PLCs are used to automate processes in industries such as manufacturing, automotive, and food processing.

• They can control machinery, equipment, and processes by receiving input from sensors and other devices.

• PLCs can be programmed to perform specific tasks, such as turning on/off motors, regulating temperature, and monitor...read more

Half duplex communication allows data to be transmitted in both directions, but not simultaneously.

• Data can be sent and received, but not at the same time

• Common examples include walkie-talkies and CB radios

• Requires a switch between sending and receiving modes

AC drives use alternating current to control the speed of an electric motor, while DC drives use direct current for the same purpose.

• AC drives are more commonly used due to their ability to provide variable speed control and energy efficiency.

• DC drives are simpler in design and are often used in applications where precise speed control is required, such as in cranes or elevators.

• AC drives are typically more cost-effect...read more

3Wire RTD is preferred over 2Wire RTD due to better accuracy and noise reduction.

• 3Wire RTD compensates for lead wire resistance, resulting in more accurate temperature measurements.

• 3Wire RTD provides better noise reduction compared to 2Wire RTD.

• 3Wire RTD allows for easier implementation of temperature compensation techniques.

• 2Wire RTD is more susceptible to lead wire resistance errors and noise interference.

Lead resistance is the resistance encountered in the electrical leads connecting a sensor or instrument to a measuring device.

• Lead resistance can affect the accuracy of measurements by introducing additional resistance in the circuit.

• It is important to account for lead resistance when designing and calibrating instrumentation systems.

• Lead resistance can be minimized by using high-quality, low-resistance leads.

• Examples ...read more

Calibration of instruments ensures accuracy and reliability of measurements.

• Ensures accuracy and reliability of measurements

• Helps in maintaining quality standards

• Prevents errors in readings

• Increases instrument lifespan

• Compliance with regulations and standards

• Examples: calibrating a thermometer for accurate temperature readings, calibrating a pressure gauge for precise pressure measurements

Supervisory Control and Data Acquisition

• SCADA stands for Supervisory Control and Data Acquisition

• It is a system used for monitoring and controlling industrial processes

• SCADA systems are commonly used in industries such as power plants, water treatment facilities, and manufacturing plants

Network topology types refer to the layout of a computer network and how different devices are connected.

• Common types include star, bus, ring, mesh, and hybrid topologies

• Star topology has a central hub with all devices connected to it

• Bus topology uses a single cable to connect all devices in a linear fashion

• Ring topology connects devices in a circular manner

• Mesh topology has each device connected to every other device

• H...read more

Various types of communication protocols include Modbus, Profibus, HART, Foundation Fieldbus, and Ethernet/IP.

• Modbus - commonly used in industrial automation

• Profibus - used in process automation

• HART - for smart field devices

• Foundation Fieldbus - for process control

• Ethernet/IP - for industrial Ethernet communication