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What solid state componet can be used as a switch to turn current on or off?
Wiki User
∙ 9y ago
The solid state component that can be used as a switch to turn current on or off is a thyristor.
Wiki User
∙ 9y ago
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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.
What is a snubber circuit?
Snubber circuits are used for semiconductor switching devices such as transistors, SCRs, etc. When a switching device changes its state from ON-state to OFF-state, the impedandce of the device abruptly jumps to a very high level, blocking the current. But the current still tends to keep flowing through the switch, which induces a high voltage across the switch. The faster the current decreases, the higher the induced voltage becomes. It may reach to sufficiently high level to destroy the switch. If the switch is unable to withstand the high induced voltage, it will be destroyed, and can no more block the current as an OFF-state switch. To avoid this, an auxiliary network is connected across the switch that prevents the induced voltage from going too high. The network is called a snubber. Conversely, when a switching device changes its state from OFF-state to ON-state, the impedance of the device abruptly goes down to nearly zero, allowing current to flow freely. The problem in this case is that the current does not start to flow uniformly through the switch. This is because the switch does not recover its conductivity over the whole its cross-sectional area simultaneously. Some part of the area may be first open, and the current flow is concentrated to this relatively small portion of the switch, which may cause overheating and eventually failure. Thus some semiconductor switches should be protected from too fast increase of current. This is another function of a snubber. In view of above discussion, the snubber circuit is someting like a "bumper." It alleviates rise of voltage when the switch is turning OFF, and alleviates rise of current when the switch is turning ON, to a safe level.
Difference between relay and solid state relay?
All solid state relays are relays, but not all relays are solid state relays. There are three basic kinds of (protective) relays I know of: electromechanical (rely on induced voltages and currents to spin disks or energize solenoids), solid state (built with solid state parts - basically prerequisites to microprocessors), and microprocessor based relays (fancy computers).
What does a thyristor do in a circuit?
A thyristor is a solid state three terminal electronic power switch with two power terminals which carry the operational part of the device current and one gate or trigger terminal which is used to switch on the thyristor when required.Whenever the current flowing though it changes diirection or simply falls to zero, a thyristor will switch off.Unlike a transistor, after its gate/trigger signal is removed a thyristor will remain switched on for as long as the direction of the current flowing through it remains the same, even if the amperage of that current changes.Unlike a mechanical switch the thyristor has operational supply polarities ( positive & negative of the supply ) which have to be observed. Therefore it can switch on and conduct for one supply polarity only.Since it is a solid state device a thyristor can operate at much faster switching speeds than any electro-mechanical switch.With a DC supply of correct polarity, a thyristor will conduct when triggered but will not then switch off till the current is interrupted by some other means such as removal of the supply or by use other, much more complex, circuitry which forces the current to flow in the reverse direction.With an AC supply, when triggered a thyristor will conduct when the supply is of correct polarity and will then automatically switch off when the AC supply polarity reverses.For controlled operation in both directions, using the gate as a trigger on the both the forward and the reverse part of the AC Supply, a second thyristor connected with reverse polarity has to be used in parallel with the first one. This idea is basically what is used to make AC lamp dimmers nowadays.========================================================A thyristor is a transistor having a thyratron-like characteristic; as collector current is increased to a critical value, the alpha (amplification factor) of the unit rises above unity to give a high-speed triggering action.That description just given (now shown in italics) is wrong! It is not for a thyristor but for a thermistor!A thermistor is a device with 2 wires coming out of it which changes its resistance to electrical current flow as its temperature is changed. They are used in devices that have to perform some job based on the temperature of the medium they are in.The 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 pulse, and continue to conduct for as long as they are forward biased. (That is, for as long as the voltage across the device has not reversed).Some sources define silicon controlled rectifiers and thyristors as synonymous. Other sources define thyristors as a larger set of devices with at least four layers of alternating N and P-type material.========================================================Re. the error shown in italics above... The first answer at the top of the page is correct: a thyristor (aka SCR or Silicon Controlled Rectifier) is a four layer solid-state switch, and a thermistor is a temperature-sensitive device consisting of a material with a high thermal coefficient of resistance, either positive or negative.Thyristors are solid-state semiconductor devices with four layers of alternating N- and P-type material. They act as bi-stable switches, conducting when their gate receives a current pulse, and continue to conduct for as long as they are forward-biased (That is, as long as the voltage across the device has not reversed).
Semiconductors are also called?
Solid state devices.
Why you called it solid state switch?
Solid state refers to electrical / electronic devices without moving parts.
What is advantage of digital relays?
They can be used as a kind of safety switch to allow a circuit with a small current through to switch on a circuit that will hve a larger current flowing through it.
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.
When an scr turns on it acts like a?
An SCR, a silicon-controlled rectifier, is a four-layer solid state current controlling device. When it turns on it acts like an electronic switch and rectifier.
Does ionic compounds counduct an electric current in the molten state?
yes, but not in the solid state
What is Triac?
A triac is a high voltage AC solid state relay it is switched on by applying a dc at the gate it can't be used to switch DC because it stay on while current is flowing even when the gate is low but with AC the current stop flowing when the cycle go zero and will switch of if the gate is low
What component is used as a high power solid state AC switch?
Triac.
Does lightning have a solid state?
No. Lightning is an electric current flowing through ionized air.
How does a solid state contactor work?
A solid state relay (SSR) is an electronic switching device in which a small control signal controls a larger load current or voltage. It comprises a voltage or current sensor which responds to an appropriate input (control signal), a solid-state electronic switching device of some kind which switches power to the load circuitry either on or off, and some coupling mechanism to enable the control signal to activate this switch without mechanical parts.
What is a silicon-controlled rectifier?
A silicon-controlled rectifier is a semiconductor device that is used as a switch in an electrical circuit. It's a solid state direct current (DC) electronic switch. There is a ton of information including a detailed description of the SCR and a list of applications at the Wikipedia article. A link is posted below.
How does a pressure switch work?
Pressure switches work differently depending on the type of switch you are referring to. The two main types are electromechanical and solid-state types.
Why do ionic crystals conduct electric current in the solid phase liquid phase or when dissolved in water but do not conduct electric current in the solid plase?
In solid state the ions are packed very tightly, so ions are not free to move, therefore no conduction.
