why thyristor is called latching device?

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1 Answer

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.
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Related questions

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.

What is holding current and latching current in SCR ?

Description : What is holding current and latching current in SCR? Draw the gate characteristics of an SCR and explain the characteristics. What are the different signals which can be used for turning on SCR by gate control? compare them.

Last Answer : (i) Holding Current: Holding current is defined as the minimum anode current required to maintain conducting SCR in the on-state.  (ii) Latching Current: Latching current is defined as the ... the on-state immediately after the SCR has been turned on and the gate signal has been removed.

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

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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.

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Last Answer : Thyristor commutation means turning off thyristor.

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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.

Thyristor can be protected from over voltages by using

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

Leakage current flows through the thyristor in

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

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Last Answer : The point at which SCR is triggered is known as firings angle of thyristor.

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Last Answer : Yes, SCR is a thyristor. Thyristor is the family and SCR is the member of that family but SCR is universally known as thyristor.

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Last Answer : thyristor

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Last Answer : Yes ,it is one of the main advantage using thristors as a  switch in DC  circuit ,it has a high current gain

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Last Answer : Thyristor Gate Drive Circuit: The thyristor can be turned on by pulse voltage signal at gate terminal and it does not require continuous drive signal like the transistor. The gate ... circuit provide required minimum gate voltage and gate current then the thyristor conducts properly.

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Description : parallel operation of MOSFET can be done more easily as compared to thyristor. why?

Last Answer : Parallel operation of MOSFET can be done more easily as compared to thyristor because the resistance of MOSFET is increases with increase in temperature. MOSFET have the positive temperature coefficient. In ... the parallel operation of MOSFET can be done more easily as compared to the thyristor.

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Last Answer : By using some circuit the forward DC current of thyristor is forced to zero is called forced commutation.

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Last Answer : Natural commutation is also called as line Communication. The turning off of thyristor due to AC supply is called natural commutation or line commutation. If the thyristor is connected to AC supply ... connected to positive and anode terminal get connected to negative, this turns off the thyristor.

can we turn off thyristor using Gate?

Last Answer : No we cannot turn off normal thyristor using Gate.

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Last Answer : Thyristor conducts when the anode voltage is greater than cathode and when the current provided to Gate.

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Wagner earthing device is used to eliminate errors due to?

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

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Component F in the illustrated device is for _________. EL-0033 A. short circut protection B. latching the trip unit closed after resetting the breaker C. overload protection D. providing a flexible connection between the input terminal G and the tripping unit E

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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

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Last Answer : Gate signal is to be applied to the thyristor to trigger the thyristor ON in safe mode. When the thyristor starts conducting the forward current above the minimum value, called Latching current, the gate ... which is applied to trigger the device in no longer require to keep the scr in ON position.

What is latching current in SCR?

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