0
Why do you require the synchronized pulse for triggering the SCR?
Wiki User
∙ 7y ago
Heart beat
Wiki User
∙ 7y ago
Add your answer:
Earn +20 pts
What happens when negative pulse applied to scr?
It turns off. Once the SCR is turned on (fired) it stays on until the voltage across it goes to zero. One way to do that is to hit it with a negative pulse. You need to be careful about how large that negative pulse is, though, as you could destroy the SCR.
What is the name of the scr or triac triggering system that triggers the output device at the same point on each ac cycle?
Diac
What is the name of the SCR or TRIAC triggering system that triggers the output device at the same point on each ac cycle on food processors?
Not a precise question as devise configuration is not mentioned. Assume bridge (half or full) configuration. The method is PMW (Pulse Width modulation). Also known as a "chopper".
What are some ways an SCR is triggered?
A silicon-controlled rectifier (SCR) can be triggered (or turned on) by forward voltage, temperature, dv/dt (the derivative of the voltage with respect to time), light, or via a gate (the SCR is triggered when sufficient voltage passes through the gate). Gate triggering is the most common method.
How do you control high voltage using SCR?
By giving proper gate triggering voltage... it can used to control the high power application like ordinary pn junction diode.
What happen when plus ve gate pulse given to reverse baise scr?
You cannot turn an SCR off by reverse biasing the gate. Once it is on (anode to cathode), it stays on until the forward current AND the gate current drops to the required threshold level. That said, you can pulse the anode negatively to turn an SCR off, so long as you don't exceed the reverse bias limits of the device. This is how (photographic) flash devices, for one example, can modulate the duration of the flash.
How is an SCR turned off?
Once an SCR has been turned on by means of a gate pulse, it latches, or remains on. The only way to turn the SCR off is to either remove the anode to cathode voltage, remove the load current (SCR's have a minimum current below which they will not fire), or reverse bias the SCR. If the SCR is used in an AC circuit, turn off is easy. This is because the voltage falls to zero, then reverse biases the SCR every cycle. This naturally turns off the SCR. In fact, you have to re-trigger the gate every cycle to turn it back on. In a DC circuit, the SCR must be reset by some means as mentioned above. Once the SCR fires, there is nothing you can do to the gate to control the device. The gate only turns it on, not off. There is a similar device, called a GTO, or gate-turn-off device, that can be turned off via the gate. Once an SCR is on it will not turn -off unless the minimum holding current is met. that can be accomplished by reversing anode polarity or by decreasing loading to below holding current
What is CMOS latch up?
Latch-up in short is defined as the creation of a low impedance path between the power supply rails by the triggering of parasitic, four-layer bipolar structures (SCR’s) inherent in CMOS technology.
Why SCR is not called GCR?
because it is gcr not scr
Does an SCR work on DC or ac?
SCR's are mainly used in AC circuits. They could be used in DC circuits but they then would not be able to turn off. They require the zero crossing of the AC circuit to turn off. Then when positively biased they can be turned back on.
What is the basic function of the SCR's gate electrode?
The SCR's gate electrode is used to turn the SCR on, i.e. fire it.
What is a signal pulse transformer?
usually a small transformer ferrite rather than iron core for short pulses it is more for isolation than anything else trigger for scr or triac the previous question for a power pulse transformer these are in cars ignition transformers the newer cars generally have one on each cylinder the computer may feed may feed a signal pulse through the small transformer to isolate the computer from the big one. to an scr to discharge a capacitor thru the ignition transformer (cars use the terms condenser and coil)
