During forward blocking state, a thyristor is associated with .

During forward blocking state, a thyristor is associated with . (A) Large current and low voltage (B) Low current and large voltage (C) Medium current and large voltage (D) None of the above
by

1 Answer

Answer :

A
by

Related questions

During forward blocking state, the SCR has:

Description : During forward blocking state, the SCR has:

Last Answer : During forward blocking state, the SCR has: low voltage, large current

What is the difference between SCR and thyristor?

Description : What is the difference between SCR and thyristor?

Last Answer : SCR is a type of thyristor. Like GTO, IGCT, MCT, TRIAC, DIAC etc. are the types of thyristor.

The turn-off time of a thyristor is 30 is at 50°C. What is its turn-off time at 100°C ?

Description : The turn-off time of a thyristor is 30 is at 50°C. What is its turn-off time at 100°C ?

Last Answer : The turn-off time of a thyristor is 30 is at 50°C. What is its turn-off time at 100°C ? 60 microsecond

In thyristor. holding current is

Description : In thyristor. holding current is (A) More than the latching current (B) Less than the latching current (C) Equal to latching current (D) None of the above

Last Answer : In thyristor. holding current is less than the latching current

The typical ratio of latching current to holding current in a 20A thyristor is :

Description : The typical ratio of latching current to holding current in a 20A thyristor is : (A) 5.0 (B) 2.0 (C) 1.0 (D) 0.5

Last Answer : The typical ratio of latching current to holding current in a 20 A thyristor is  2.0

thyristor have how many terminals?

Last Answer : Thyristor have three terminals anode, cathode and Gate.

thyristor can be turned off by?

Description : thyristor can be turned off by?

Last Answer : Thyristor can be turned off by making anode potential equal to cathode potential or by making anode potential less than cathode potential.

what is thyristor commutation?

Last Answer : Thyristor commutation means turning off thyristor.

why thyristor is called semi controlled device?

Last Answer : Thyristor can only be turned on by small gate pulse but it cannot be turn off by using gate hence thyristor is called semi controlled device.

why thyristor is called latching device?

Last Answer : Thyristor can be turn on by positive gate pulse and the current will continue to flow through the device even when the gate voltage is low hence thyristor is called latching device.

What losses occur in a thyristor during working conditions?

Description : What losses occur in a thyristor during working conditions?

Last Answer : a. Forward conduction losses b. Loss due to leakage current during forward and reverse blocking. c. Switching losses at turn-on and turn-off. d. Gate triggering loss.

What is Thyristor ?

Description : What is Thyristor ?

Last Answer : : A thyristor is a solid state semiconductor device consisting of four layers of P and N-type components. This is especially true of a dual mode switch.

Which of the devices listed is indicated by the electronic symbol lettered as 'A', shown in the illustration? EL-0016 A. Thyristor B. Diode C. Capacitor D. Transistor

Description : Which of the devices listed is indicated by the electronic symbol lettered as 'A', shown in the illustration? EL-0016 A. Thyristor B. Diode C. Capacitor D. Transistor

Last Answer : Answer: B

What does the arrangement at coordinates '62E' shown in the illustration represent? EL-0099 A. Position recording drum and stylus B. Temperature compensating thyristor C. Miniature bridge rectifier D. Twisted wire pair within a shield

Description : What does the arrangement at coordinates '62E' shown in the illustration represent? EL-0099 A. Position recording drum and stylus B. Temperature compensating thyristor C. Miniature bridge rectifier D. Twisted wire pair within a shield

Last Answer : Answer: D

Figure 'B' shown in the illustration represents a/an ____________. EL-0067 A. silicon controlled rectifier B. junction field effect transistor C. diac thyristor D. IG MOS field effect transistor

Description : Figure 'B' shown in the illustration represents a/an ____________. EL-0067 A. silicon controlled rectifier B. junction field effect transistor C. diac thyristor D. IG MOS field effect transistor

Last Answer : Answer: A

A triac thyristor functions as a control device and is basically ________________. A. two NPN transistors in parallel with a common base lead B. a diode in series with a temperature sensitive capacitor C. two back-to-back SCR's with a common gate lead D. a triode tube with an extra heavy grid element

Description : A triac thyristor functions as a control device and is basically ________________. A. two NPN transistors in parallel with a common base lead B. a diode in series with a temperature sensitive capacitor C. two ... -back SCR's with a common gate lead D. a triode tube with an extra heavy grid element

Last Answer : Answer: C

Figure 'A' of the diagram shown in the illustration represents a/an ____________. EL-0078 A. silicon controlled rectifier B. IG or MOS field effect transistor C. triac thyristor D. junction field effect transistor

Description : Figure 'A' of the diagram shown in the illustration represents a/an ____________. EL-0078 A. silicon controlled rectifier B. IG or MOS field effect transistor C. triac thyristor D. junction field effect transistor

Last Answer : Answer: B

Figure 'B' of the diagram shown in the illustration represents a/an ____________. EL-0065 A. silicon controlled rectifier B. junction field effect transistor C. diac thyristor D. IG or MOS field effect transistor

Description : Figure 'B' of the diagram shown in the illustration represents a/an ____________. EL-0065 A. silicon controlled rectifier B. junction field effect transistor C. diac thyristor D. IG or MOS field effect transistor

Last Answer : Answer: B

What are the different losses that occur in thyristor while operating?

Description : What are the different losses that occur in thyristor while operating?

Last Answer : Different losses that occur are Forward conduction losses during conduction of the thyristor Loss due to leakage current during forward and reverse blocking. Power loss at gate or Gate triggering loss. Switching losses at turn-on and turn-off.

Why thyristor is considered as Charge controlled device?

Description : Why thyristor is considered as Charge controlled device?

Last Answer : During the triggering process of the thyristor from forward blocking state to forward conduction state through the gate signal, by applying the gate signal (voltage between gate and cathode) increases the ... By controlling the amount of charge we can control the turning on time of the scr.

Do you know the advantages of speed control using thyristor?

Description : Do you know the advantages of speed control using thyristor?

Last Answer : A: Advantages: 1. Fast Switching Characteristics than Mosfet, BJT, IGBT 2. Low cost 3. Higher Accurate.

What Are The Advantages Of Speed Control Using Thyristor?

Description : What Are The Advantages Of Speed Control Using Thyristor?

Last Answer : Advantages : Fast Switching Characterstics than Mosfet, BJT, IGBT. Low cost. Higher Accurate.

How output frequency is varied in case of a thyristor?

Description : How output frequency is varied in case of a thyristor?

Last Answer : The output frequency is varied by varying the turn off time of the thyristors in the inverter circuit, i.e. the delay angle of the thyristors is varied.

Why circuit turn off time should be greater than the thyristor turn-off time?

Description : Why circuit turn off time should be greater than the thyristor turn-off time?

Last Answer : Circuit turn off time should be greater than the thyristor turn-off time for reliable turn-off, otherwise the device may turn-on at an undesired instant, a process called commutation failure.

How can a thyristor turned off?

Description : How can a thyristor turned off?

Last Answer : A thyristor can be turned off by making the current flowing through it to zero.

What are the different methods to turn on the thyristor?

Description : What are the different methods to turn on the thyristor?

Last Answer : a. Forward voltage triggering b. Gate triggering c. dv/dt triggering d. Temperature triggering e. Light triggering

What is Thyristor?

Description : What is Thyristor?

Last Answer : Thyristor is a four or more layer semiconductor device & having 3 or more junctions. It is also called Silicon Controlled Rectifiers (SCR). A healthy SCR must block in both the directions at least 1MQ resistance, a fused SCR will conducts in both directions. 

What is purpose of connecting thyristor bridges in parallel?

Description : What is purpose of connecting thyristor bridges in parallel?

Last Answer : Thyristor bridges are connected in parallel to improve current rating.  

Why reactors are provided in Thyristor bridges?

Description : Why reactors are provided in Thyristor bridges? 

Last Answer : Reactors are provided to limit the rate of rise of current (di/dt) in the device, thereby avoiding possible damage to the device. They also effect a proper sharing of load among thyristor bridges when connected in parallel. 

What is the purpose of RC network across thyristor?

Description : What is the purpose of RC network across thyristor?

Last Answer : RC network across each thyristor protects against Hole Storage Effect.  

What is Thyristor?

Description : What is Thyristor?

Last Answer : Thyristor is a four or more layer semiconductor device & having 3 or more junctions. It is also called Silicon Controlled Rectifiers (SCR). A healthy SCR must block in both the directions at least 1MΩ resistance, a fused SCR will conducts in both directions. 

In a thyristor Latching current is ________ than Holding current a) Equal b) Less c) Greater d) None

Description : In a thyristor Latching current is ________ than Holding current a) Equal b) Less c) Greater d) None

Last Answer : Ans: Greater

What is a thyristor ? What are its uses ?

Description : What is a thyristor ? What are its uses ?

Last Answer : 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 ... the latches like a open switch. This latch will always stay in open or close position.  

What is a thyristor? What is an SCR?

Description : What is a thyristor? What is an SCR?

Last Answer : A thyristor is a solid-state semiconductor device with four layers of alternating N and P-type material. They act as bi stable switches, conducting when their gate receives a current trigger, and continue ... ) is a four-layer solid state device that controls current. It is a type of thyristor.

Which of the following problem arises in D.C. motors which are fed from thyristor bridge circuits ? (a) Increased I R losses (b) Increased core losses (c) Poor commutation (d) Change in motor parameters (e) All of the above

Description : Which of the following problem arises in D.C. motors which are fed from thyristor bridge circuits ? (a) Increased I R losses (b) Increased core losses (c) Poor commutation (d) Change in motor parameters (e) All of the above

Last Answer : (e) All of the above

Describe the working principle of Thyristor operated dimmer with the help of circuit diagram.

Description : Describe the working principle of Thyristor operated dimmer with the help of circuit diagram.

Last Answer : Thyristor operated dimmer: A popular thyristor operated dimmer circuit employ TRIAC-DIAC phase control for low AC power control. During each half-cycle, the capacitor charges through (R1+VR1). When the ... time constant {C (R1+VR1)}. Thus by reducing VR1 the lamp brightness can be increased.

Is gate turn on mechanism of GTO is similar to conventional thyristor?

Description : Is gate turn on mechanism of GTO is similar to conventional thyristor?

Last Answer : Yes gate turn on mechanism of GTO is similar to conventional thyristor.

In a thyristor, the magnitude of anode current will:

Description : In a thyristor, the magnitude of anode current will:

Last Answer : In a thyristor, the magnitude of anode current will: Not change with any variation in gate current

A thyristor (SCR) turns off when the

Description : A thyristor (SCR) turns off when the  A) Gate pulse is removed B) Gate pulse is applied C) Thyristor current is below holding value D) Anode voltage is made negative

Last Answer : A thyristor (SCR) turns off when the Thyristor current is below holding value

Turn-on of a thyristor (SCR) takes place when

Description : Turn-on of a thyristor (SCR) takes place when  A) Anode to cathode voltage is positive B) Anode to cathode voltage is negative C) Positive current is applied to gate D) Anode to cathode voltage is positive and positive current pulse is applied to gate

Last Answer : Turn-on of a thyristor (SCR) takes place when Anode to cathode voltage is positive and positive current pulse is applied to gate

The number of p-n junctions in a thyristor are

Description : The number of p-n junctions in a thyristor are  A)1 B) 2 C) 3 D) 4

Last Answer : The number of p-n junctions in a thyristor are  3

A three-phase, 440 V, 50 Hz ac mains fed thyristor bridge is feeding a 440 V dc, 15 kW, 1500 rpm separately

Description : A three-phase, 440 V, 50 Hz ac mains fed thyristor bridge is feeding a 440 V dc, 15 kW, 1500 rpm separately excited dc motor with a ripple free continuous current in the dc link under all operating conditions, Neglecting the ... at half the rated speed is  (A) 0.354 (B) 0.372 (C) 0.90 (D) 0.955

Last Answer : A three-phase, 440 V, 50 Hz ac mains fed thyristor bridge is feeding a 440 V dc, 15 kW, 1500 rpm separately excited dc motor with a ripple free continuous current in the dc link under all operating conditions, Neglecting the losses, the power factor of the ac mains at half the rated speed is 0.354

A three-phase, fully controlled thyristor bridge converter is used as line commutated inverter to feed 50 kW

Description : A three-phase, fully controlled thyristor bridge converter is used as line commutated inverter to feed 50 kW power 420 V dc to a three-phase, 415 V(line), 50 Hz ac mains. Consider dc link current to be constant. The rms current of the thyristor is  (A) 119.05 A (B) 79.37 A (C) 68.73 A (D) 39.68 A

Last Answer : A three-phase, fully controlled thyristor bridge converter is used as line commutated inverter to feed 50 kW power 420 V dc to a three-phase, 415 V(line), 50 Hz ac mains. Consider dc link current to be constant. The rms current of the thyristor is 68.73 A

A single-phase fully controlled thyristor bridge ac-dc converter is operating at a firing angle of 25 and an

Description : A single-phase fully controlled thyristor bridge ac-dc converter is operating at a firing angle of 25o and an overlap angle of 10o with constant dc output current of 20 A. The fundamental power factor (displacement factor) at input ac mains is  (A) 0.78 (B) 0.827 (C) 0.866 (D) 0.9

Last Answer : A single-phase fully controlled thyristor bridge ac-dc converter is operating at a firing angle of 25o and an overlap angle of 10o with constant dc output current of 20 A. The fundamental power factor (displacement factor) at input ac mains is 0.78

a single phase full wave midpoint thyristor converter uses a 230/200V transformer with centre tap on the

Description : a single phase full wave midpoint thyristor converter uses a 230/200V transformer with centre tap on the secondary side. The P.I.V per thyristor is   (A) 100V (B)141.4V (C)200V (D)282.8V

Last Answer : d

Anode current in an thyristor is made up of

Description : Anode current in an thyristor is made up of   (A) electrons only (B) electrons or holes (C) electrons and holes (D) holes only

Last Answer : Anode current in an thyristor is made up of electrons and holes 

In a thyristor, holding current is

Description : In a thyristor, holding current is   (a) More than latching current IL (b) Less than IL (c) Equal to IL (d) Very small

Last Answer : In a thyristor, holding current is Less than IL

Thyristor can be protected from over voltages by using

Description : Thyristor can be protected from over voltages by using

Last Answer : Thyristor can be protected from over voltages by using Voltage clamping device

Leakage current flows through the thyristor in

Description : Leakage current flows through the thyristor in

Last Answer : Leakage current flows through the thyristor in Forward blocking mode and Reverse blocking mode.

In a thyristor Latching current is than holding current: -

Description : In a thyristor Latching current is than holding current: - a) equal b) less c) greater d) none of the above

Last Answer : In a thyristor Latching current is than holding current: - greater