• Home
  • Basics
  • Electrical Circuits
  • Power Systems
  • Power Electronics
  • MCQ

WatElectrical.com

Electricals Made Easy

You are here: Home / MCQ / Silicon Controlled Rectifiers Question & Answers

Silicon Controlled Rectifiers Question & Answers

September 1, 2021 By Wat Electrical Leave a Comment

This article lists 100 Silicon Controlled Rectifiers MCQs for Engineering Students. All the Silicon Controlled Rectifiers Questions & Answers given below includes solution and link wherever possible to the relevant topic.

Silicon Controlled Rectifiers also represented as SCR is a semiconductor diode operating in a single direction. It was invented in the year 1957 by Tanenbaum at Bell labs. The purpose of designing an SCR is to control high voltage applications. An SCR is fabricated with four layers namely p-n-p-n, forming 3 junctions J1, J2, and J3 consisting of 3 main terminals, input, and output terminals that include Anode, Cathode terminal, and a gate terminal.

The operation of SCR in forward bias and reverse bias depends on the quantity of voltage applied at the gate. It operates in three modes namely forward blocking mode (off state), forward conduction mode (on state), and reverse blocking mode (off state). The process of turning on an SCR is called triggering. This can be achieved by 5 processes that include forward type voltage triggering, light triggering, dv/dt triggering, and temperature-based triggering. The process of turning off SCR is called Commutating, this can be achieved using Class A, ClassB, ClassC, Class D, Class E type SCR’s.

SCR benefits in terms of handling high voltage, protect from short circuits, and can control power to load. Applications of an SCR circuit are lamp dimmers, power-based regulators, and motors.

1). A silicon controlled rectifier (SCR) is designed with _____ material.

Hint
2). How many layers is SCR designed with?

Hint
3). Who developed SCR?

Hint
4). SCR is a ___ component.

Hint
5). How many pins does an SCR consist of ?

Hint
6). Which of the following is a charge representation for cathode in SCR?

Hint
7). Which of the following is a charge representation for anode in SCR?

Hint
8). How many junctions does SCR diode have?


Hint
9). SCR is also known as ______.

Hint
10). An SCR operates in ____ number of directions.

Hint
11). What is the charge applied on SCR’s gates terminal to make it operate?

Hint
12). In how many modes does an SCR operate?

Hint
13). Which of the following is the off state mode of SCR?

Hint
14). Which of the following is the on state mode of SCR?

Hint
15). What is the charge applied to anode of SCR during forward type blocking mode?

Hint
16). What is the charge applied to cathode of SCR during forward type blocking mode?

Hint
17). What is the charge applied to the gate of SCR during forward type blocking mode?

Hint
18). Which of the following junctions of an SCR conducts in forward bias in forward blocking type mode?

Hint
19). Which of the following junctions of an SCR conducts in reverse bias in forward blocking type mode?

Hint
20). How much leakage current flows through J2 of SCR in forward blocking type mode?

Hint
21). Which of the following junction of SCR in forward blocking type mode goes into Avalanche breakdown when the junction reaches maximum limit?

Hint
22). Which of the following junction of SCR in forward blocking type mode starts conducting after avalanche break down?

Hint
23). How many conditions are present to turn on SCR from blocking to conducting mode?

Hint
24). How much quantity of latching current is required for a SCR in forward conduction mode to maintain in On state?

Hint
25). How much quantity of current is required for a SCR in forward conduction mode to OFF SCR?

Hint

Silicon Controlled Rectifiers MCQs for Interviews

26). What is the charge applied on SCR’s anode terminal to make it operate in an reverse type blocking mode?

Hint
27). What is the charge applied on SCR’s cathode terminal to make it operate in an reverse type blocking mode?

Hint
28). Which of the following junctions of an SCR conducts in reverse bias in reverse blocking type mode?

Hint
29). Which of the following junctions of an SCR conducts in forward bias in reverse blocking type mode?

Hint
30). At what junctions is avalanche breakdown observed for an SCR operating in reverse blocking type mode?

Hint
31). What is the value of voltage type blocking rate for reverse and forward SCR?

Hint
32). How many methods an SCR has to turn on?

Hint
33). Which of the following is the method that turns on SCR when cathode and anode is applied with increasing forward voltage and gate is open circuited?

Hint
34). Which of the following is the method that turns on SCR when depletion region’s width reduces as increase in temperature?

Hint
35). Which of the following are the applications of an SCR circuit?

Hint
36). Which of the following are the methods used for turning of an SCR diode?

Hint
37). In to how many classes do a forced type commutation is divided into?

Hint
38). Which of the following class of commutation is self commutated with resonating load in an SCR?

Hint
39). Which of the following class of commutation is self commutated with LC based circuit in an SCR?

Hint
40). Which of the following class of commutation is Cor based LC type switched using other load SCR?

Hint
41). Which of the following class of commutation is LC or C type switched using auxiliary based SCR?

Hint
42). Which of the following class of SCR commutation is an external based pulse source?

Hint
43). Which of the following are the characteristics of a natural based commutation of SCR thyristor?

Hint
44). Which of the following are the characteristics of a forced based commutation of SCR thyristor?

Hint
45). _______ is called as the process to operate a thyristor.

Hint
46). ______ is called as the process to off a thyristor.

Hint
47). What is the equation of peak current for an Class B type thyristor?

Hint
48). What happens in Class A type SCR when current is passed through anode?

Hint
49). At what condition does an SCR stops operating in Class A?

Hint
50). Up to what condition SCR operates in reverse bias type condition in Class A?

Hint

Silicon Controlled Rectifiers Exam Questions & Answers

51). Up to what condition does a capacitor charges in Class B type SCR?

Hint
Read more about Capacitor.
52). How many component does an class B SCR have on supplying gate voltage?

Hint
53). What is value of current flowing through Class B type SCE in a RL load?

Hint
54). What is the value of Inductance when constant value of current flows through load in Class B SCR?

Hint
55). How is load connected in Class B type SCR with respect to reactance?

Hint
56). Which type of wave pass through LC circuit in Class B SCR?

Hint
57). What is the value of reverse type current with respect to load type current to turn off Class B type SCR?

Hint
58). What is the value of re-applied based voltage and rated based value of Class B SCR?

Hint
59). How many SCR's does Class C type SCR have?

Hint
60). Which of the following component is used in an class E type SCR to block saturation?

Hint
Read more about Transformer.
61). What is the value of voltage drop of a transformer in Class E SCR when it carries load current to other components in circuit?

Hint
62). On which of the following factors an SCR is selected for an application?

Hint
63). When an SCR hits break over voltage, it further results in raise in critical based rate of voltage of an cathode and anode. This statement is defined as ___ condition of SCR.

Hint
64). Which of the following is the SCR condition, when current is minimized until either one or all the transistors enter cutoff mode?

Hint
65). An SCR acts like ______ type of component.

Hint
66). What is the value of current applied to one complete cycle in an SCR without disturbing its performance according to peak cycle based surge on current parameter?

Hint
67). An SCR in DC type motor has _______ number of SCR’s.

Hint
Read more about DC Motors.
68). During positive cycle of motor operation how many SCR operate in forward bias?

Hint
69). During negative cycle of motor operation how many SCR operate in forward bias?

Hint
70). Which of the following are different types of SCR’s?

Hint
71). How many pins does an discrete type plastic SCR package has?

Hint
72). What is the capacity of discrete type plastic SCR package?

Hint
73). What is the capacity of plastic type module SCR package?

Hint
74). Which of the following are the characteristics of a stud type SCR?

Hint
75). What is the capacity of stud type SCR?

Hint

Silicon Controlled Rectifiers MCQs With Answers

76). Which of the following is the disadvantage provided by stud type SCR?

Hint
77). Which of the following is the advantage of flat base type SCR?

Hint
78). What is the capacity of flat base type SCR?

Hint
79). What is the capacity of press pack type SCR?

Hint
80). Asymmetrical type SCR’s are also named as ________.

Hint
81). Which of the following is the function of an asymmetrical type SCR?

Hint
82). How much reverse type breakdown ratings does an ASCR have?

Hint
83). Which of the following are the applications of a RSCR?

Hint
Read more about Inverters.
84). On comparing SCR with SCS switch, which one turns off when positive voltage is given to its anode?

Hint
85). Which of the following are the applications of an SCS?

Hint
86). Which of the following switch is specifically used in AC type applications?

Hint
87). Which of the following are the applications of TRIAC?

Hint
Read more about Electronic Light Dimmer Circuits Using TRIAC.
88). Which of the following are examples of semiconducting materials?

Hint
89). What are the +ve charge carriers of semiconductors?

Hint
90). What are the -ve charge carriers of semiconductors?

Hint
91). Which of the following semiconducting charge carriers have both positive and negative?

Hint
92). To form a p-type type semi conductor which of the following charge carriers are doped?

Hint
93). To form a n-type type semi conductor which of the following charge carriers are doped?

Hint
94). Holes charge carriers are also known as ______.

Hint
94). N-type charge carriers are also known as ______.

Hint
95). Which of the following are the elements of n-type semi conductor?

Hint
96). Which of the following are the elements of p-type semi conductors?

Hint
97). An Shockley diode has ______ number of layers.

Hint
98). Which of the following is the primary characteristic of a Shockley diode?

Hint
99). Who invented Shockley diode?

Hint
100). Which of the following are the components of a Shockley diode?

Hint
clock.png

Time is Up!

clock.png

Time's up

Leave a Reply

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

SEARCH HERE!

Recent Posts

  • Demand Factor : Factors, Load Calculation & Its Applications
  • Residual Current Device : Circuit, Working & Its Applications
  • Electron Flow : Working, Formula & Its Differences
  • Coefficient of Coupling : Derivation, Working & Its Example
  • Different Types of Resistors and Its Color Code Calculation
  • Eddy Current : Working, Advantages, Loss, Braking System & Its Applications
  • Voltage Follower : Circuit, Working, Purpose & Its Applications
  • Phase Shifting Transformer : Construction, Working & Its Applications
  • Non Inverting Op Amp : Circuit, Working, Derivation, Types and Applications
  • Shunt Reactor : Working, Types, Characteristics & Its Applications

Categories

  • Basics
  • Electrical
  • Electrical Circuits
  • Electrical Machines
  • Electrical Measurements
  • Electrical Projects
  • Electromagnetic Fields
  • Power Electronics
  • Power Plant
  • Power Systems

Copyright © 2021 · WatElectrical.com | Contact Us | Privacy Policy