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And SCR will conduct appreciable current when it is gated "on" and thus "told" to conduct. A silicon controlled rectifier(SCR) is an electronically controlled DC switch, and the gate is the terminal to which the control voltage is applied. Use the link below to learn more.
Wiki User
∙ 14y ago
Wiki User
∙ 9y agoWhen the gate is 'on' the SCR is said to conduct. SCR is a silicon controlled rectifier and is a type of thyristor.
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Define latching current in scr?
Latching Current is the minimum current needed on the gate to fire or trigger an SCR.
What is holding current of SCR?
It is a current
How do you calculate holding current of scr when latching current is given?
we know that ratio of holding current to latching current in scr is 0.4.
Is scr current controlled device?
yes it is current controlled
Contrast the scr and the triac?
Essentially an Scr is a solid state switch that will only allow current to flow in one direction. A triac is essentially two scr's in Anti- parallel that allows current to pass in both directions.
An SCR conducts appreciable current when Anode and gate are both negative?
No, an SCR conducts when the anode and gate are both positive.
What is the effect of holding current in SCR?
The effect of holding current (anode to cathode) in an SCR is to retain the turned on state, even in the absence of any gate voltage. When used as an AC voltage controller, the SCR conducts from the moment the gate and anode goes positive until the anode goes negative on the next zero line crossing, irrespective of any further transistions on the gate.
Define latching current in scr?
Latching Current is the minimum current needed on the gate to fire or trigger an SCR.
What is holding current of SCR?
It is a current
How do you calculate holding current of scr when latching current is given?
we know that ratio of holding current to latching current in scr is 0.4.
Can a diac trigger scr?
No, a Diac cannot trigger an SCR because when the Diac turns ON, the current through the Diac is around 9 mA. The gate threshold current of an SCR is typically 5 mA, which is less. So the SCR can get damaged due to this high gate current.
What happens if voltage is constant and current is varying when an scr triggers?
Even if the current is varying,as long as the current reaches the value required to trigger the SCR, it will snap into operation. The SCR will remain in operation until the current through it drops to a value below the holding current.
Is scr current controlled device?
yes it is current controlled
What happens if gate voltage of an ON scr is decreased?
A: Nothing after an SCR conduct the gate has no more control to shut it off. So how do we shut off an SCR two way reverse the voltage on the SCR or reduce the current below the holding current. SCR are not DC friendly once on they stay on until see above
Is scr is high current rating?
yes
Why scr is used as a rectifier?
it conducts in only one direction. it can also be used as a switch and made to not conduct at all.
Contrast the scr and the triac?
Essentially an Scr is a solid state switch that will only allow current to flow in one direction. A triac is essentially two scr's in Anti- parallel that allows current to pass in both directions.
