Inst ToolsInst ToolsInst Tools
  • Courses
  • Automation
    • PLC
    • Control System
    • Safety System
    • Communication
    • Fire & Gas System
  • Instrumentation
    • Design
    • Pressure
    • Temperature
    • Flow
    • Level
    • Vibration
    • Analyzer
    • Control Valve
    • Switch
    • Calibration
    • Erection & Commissioning
  • Interview
    • Instrumentation
    • Electrical
    • Electronics
    • Practical
  • Q&A
    • Instrumentation
    • Control System
    • Electrical
    • Electronics
    • Analog Electronics
    • Digital Electronics
    • Power Electronics
    • Microprocessor
  • Request
Search
  • Books
  • Software
  • Projects
  • Process
  • Tools
  • Basics
  • Formula
  • Power Plant
  • Root Cause Analysis
  • Electrical Basics
  • Animation
  • Standards
  • 4-20 mA Course
  • Siemens PLC Course
Reading: Interview Questions on Electronics and Instrumentation
Share
Notification Show More
Font ResizerAa
Inst ToolsInst Tools
Font ResizerAa
  • Courses
  • Design
  • PLC
  • Interview
  • Control System
Search
  • Courses
  • Automation
    • PLC
    • Control System
    • Safety System
    • Communication
    • Fire & Gas System
  • Instrumentation
    • Design
    • Pressure
    • Temperature
    • Flow
    • Level
    • Vibration
    • Analyzer
    • Control Valve
    • Switch
    • Calibration
    • Erection & Commissioning
  • Interview
    • Instrumentation
    • Electrical
    • Electronics
    • Practical
  • Q&A
    • Instrumentation
    • Control System
    • Electrical
    • Electronics
    • Analog Electronics
    • Digital Electronics
    • Power Electronics
    • Microprocessor
  • Request
Follow US
All rights reserved. Reproduction in whole or in part without written permission is prohibited.
Inst Tools > Blog > Instrumentation Interview Questions > Interview Questions on Electronics and Instrumentation

Interview Questions on Electronics and Instrumentation

Last updated: March 23, 2019 4:58 pm
Editorial Staff
Instrumentation Interview Questions
No Comments
Share
9 Min Read
SHARE

Study the most frequently asked Interview Questions on Electronics and Instrumentation engineering to prepare for the job interview.

Contents
Electronics and Instrumentation Questions1. What is a diode?2. What is a filter used for ?3. What is zener Diode? What is a voltage Regulator?4. What is transistor? What are the different types?5. What is CB, CE and CC configuration ?6. How will you test a transistor with a multimeter. ?7. What is a thyristor? What are its uses?GENERAL INSTRUMENTATION QUESTION1. What are Intrinsically safe system?2. What does a transmitter output stantfrom 3-15psi or (0.2 -1 Kg/em2) or 4 – 20 m.a. etc?3. What is force balance and motions balance principle?

Electronics and Instrumentation Questions

Interview Questions on Electronics and Instrumentation

1. What is a diode?

A diode consists of two electrodes (1) Anode (2) Cathode. The current flow is only in one direction.

A diode is the most basic solid state (semi conductor) device.The P. material has holes and the N. material has electrons.

Forward & reverse Bias :

1) Where the applied voltage overcomes the barrier potential (the p side is more positive than the n side) the current produce is large because majority carriers cross the junction in large numbers. This condition is called forward bias.

2) When the applied voltage aids the barrier potential (n side + ve than p side) the current in small. This state is known as Reverse Bias.

2. What is a filter used for ?

The half wave and full wave signals are pulsating D . C . voltages. The use of such voltages is limited to charging batteries, running D. C. motors, and a few other applications.

What we really have is a D.C. voltage that is constant in valve, similar to the voltage from a battery. To get a constant voltage from this, we can use a capacitor input filter.

3. What is zener Diode? What is a voltage Regulator?

The breakdown region of a p n diode can be made very sharp and almost vertical Diodes with almost vertical breakdown region are known as Zener Diodes.

A zener diodes operating in the breakdown region is equivalent to a battery. Because of this current through zener diode can change but the voltage remains constant. It is this constant voltage that has made the zener diode an important device in voltage regulation.

Voltage Regulator: The output remains constant despite changes in input voltage due to Zener effect.Also Read: Electronics Interview Questions & Answers

4. What is transistor? What are the different types?

A transistor is a three lagged semi conductor device. Basically a transistor means (transfer – resister). Whether the transistor is pnp or npn it resembles two diodes (back to back).

The one of the left is called emitter diodes, and the one on the right is the collector diode. Since two types of charges are involved transistor : are classified as bipolar devices.

Biasing the transistor: Emitter – Base: Forward Bias.

5. What is CB, CE and CC configuration ?

Collector – Base: Reverse Bias.

Buffer: A device or a circuit used to isolate two pt’ne circuits or stages. The emitter follows is a example of buffer.

Alpha = IC / IE Beta = IC / IE

6. How will you test a transistor with a multimeter. ?

l. Emitter +ve of meter and Base -ve output = Low resistance

2. Emitter -ve of meter and base +ve output = High resistance.

3. Collector +ve and Base -ve output = Low.

4. Collector -ve and base +ve output = High. Emitter : Collector = High Resistance.

PNP : Opposite Results.

7. What is a thyristor? What are its uses?

A thyristor is a special kind of semi conductor device that uses internal feedback to produce latching action.

Use: Used for controlling large amounts of load power in motors, heaters, lighting systems etc.

Explanation : Because of the unusual connection we have a +ve feedback also called regeneration. A change in current at any point in the loop is amplified and returned to the starting point with the same phase.

For instance if the 02 base current increases, the 02 collector current increases. This force base current through Ol. In turn this produces a large 01 collector current which drives the 02 base harder.

This build up in currents will continue until both transistors are driven in satoration. In this case the latch acts like a closed switch.

On the other hand, if something causes the 02 base current to decrease, the 02 collector current will decrease. This reduces the 01 base current. In turn, there is less 01 collector current, which reduces the 01 base current even more.

This regeneration continues until both transistors are driven into cut off. At this time the latch acts like a open switch. This latch will always stay in open or close position.

GENERAL INSTRUMENTATION QUESTION

1. What are Intrinsically safe system?

Intrinsic safety is a technique for designing elecrtical equipment for safe use in locations made nazandous by the presence of flammable gas or vapours in air.

“Defn. .” Intrinsically safe circuit is one in which any sparkor thermal effect produce either normally or under specified fault conditions is incapable of causing ingition of a specified gas or vapor in air mixture at the most easily ignited concentration.

HAZARDOUS AREAS : The specification of products or systems sold as intrinscially safe must state in what hazardous areas they are infact intrinsically safe. Universal cooling of hazadous areas has not, unfortunately, been adopted in all countries. However two sets of codiva in common use are.

2. What does a transmitter output stantfrom 3-15psi or (0.2 -1 Kg/em2) or 4 – 20 m.a. etc?

The transmitter output stance from what is known as “live zero”. This system has specific advantages:

l. The systems automatically alarms when the signal system becomes inoperative.

2. The output areas is linear ( Ratio of 1 : 5 ).

DEAD ZERO SIGNAL:

The advantage is that it does not have to be biased to true zero. A “Live zero” gives the computer additional information, so that it can takes appropriate alarm action in case of a measurement failure, because it can discriminate between a transmitter operating, but transmitting a zero measurement and a failure, in the signal system.

3. What is force balance and motions balance principle?

FORCE BALANCE PRINCIPLE : “A controller which generates and output signal by opposmg torque’s”.

The input force is applied on the input bellows which novas the beam. This crackles nozzle back pressure. The nozzle back pressure is sensed by the balancing bellows which brings the beam to balance. The baffle movement is very less about 0.002″ for full scale output.

MOTION BALANCE PRINCIPLE : “A controller which generates an output signal by motion of its parts”.

The increase in input signal will cause the baffle to move towards the nozzle. The nozzle back pressure will increase. This increase in back pressure acting on the balancing bellows, will expands the bellows, there by moving the nozzle upward. The nozzle will move untilits motion (almost) equals the input (baffle) motion.

Advantages of force Balance :

1. Moving parts are fever.

2. Baffle movement is negligible.

3. Frictional losses are less.Also Read: Electronics Questions & Answers

Don't Miss Our Updates
Be the first to get exclusive content straight to your email.
We promise not to spam you. You can unsubscribe at any time.
Invalid email address
You've successfully subscribed !

Continue Reading

Certified Control Systems Technician (CCST) Questions
Questions on Piping and Instrumentation Diagrams
100 Instrumentation Basics Questions
Electronics & Instrumentation Engineering Interview Questions For Freshers
Interview Questions on Fire Alarm System
Instrumentation Inspection and Quality Control Questions
Share This Article
Facebook Whatsapp Whatsapp LinkedIn Copy Link
Share
Leave a Comment

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Stay Connected

128.3kFollowersLike
69.1kFollowersFollow
210kSubscribersSubscribe
38kFollowersFollow

Categories

Explore More

Field Instrumentation Interview Questions and Answers
Instrumentation Lab Viva Questions
Power Plant Interview Questions & Answers
HR Interview Questions and Answers
Interview Questions on Pressure Measurement
Latest ProfiBus Questions and Answers
List of 300 Industrial Instrumentation Questions
Industrial Instrumentation Questions & Answers

Keep Learning

Interview Questions and Answers on Load Cell

Serial Communication Interview Questions

Serial Communication Interview Questions and Answers

Latest Control Valves Interview Questions

Control Valve Interview Questions and Answers

Modbus Communication Interview Questions and Answers

Modbus Communication Interview Questions and Answers

Loop Diagram

15 Loop Diagram Questions

SCADA Interview Questions

SCADA Interview Questions and Answers

Interview Questions on Transformers

Electrical & Instrumentation QC Interview Questions

PLC Questions & Answers

Programmable Logic Controller Questions and Answers

Learn More

Node-RED in PLC Automation

Node-RED in PLC Industrial Automation

Control Systems Stability and Algebraic Criteria

Concept of Stability in Control Systems

Rotary Stem Valves

Rotary Stem Valves

Transmitter Calibration Range of a Vessel Level

Transmitter Calibration Range of a Vessel Level

High Integrity Pressure Protection System HIPPS

Overview of HIPPS System

valve control system

Solenoid Valves Practical Problems

Data Protection Tips

8 Data Protection Tips For Businesses And Individuals

If Else Statement in SCL Language

If Else Statement in SCL Language

Menu

  • About
  • Privacy Policy
  • Copyright

Quick Links

  • Learn PLC
  • Helping Hand
  • Part Time Job

YouTube Subscribe

Follow US
All rights reserved. Reproduction in whole or in part without written permission is prohibited.
Welcome Back!

Sign in to your account

Username or Email Address
Password

Lost your password?