0
A thyristor is a type of semi-conductor and is used in a circuit to control the application of electrical power to a load. They are often found as the switching element in light dimmers and can be used as control elements in power supplies (variable or regulated).
Types of thyristors are diacs, triacs, sidacs and SCRs (silicon controlled rectifier).
Wiki User
∙ 14y ago
Wiki User
∙ 13y agoA Thyristor is a Silicon Controlled Rectifier (SCR) which is functionally similar to a transistor.
When voltage is applied to the gate, the SCR turns on (forward voltage only) and conducts. If it is a DC circuit, the SCR will not turn off until the supply voltage is turned off; making the SCR almost useless as a DC switch.
The SCR is useful in AC applications, allowing the engineer to effectively treat the SCR as a solid state switch.
The SCR (thyristor) COULD be treated as a fuse though, if too much current is pushed through the thyristor/SCR it would blow out, preventing an over-current condition in the rest of the circuit.
Add your answer:
Earn +20 pts
What is circuit breaker handling trolley?
handling the circuit breaker
Were is the platinum in a circuit breaker?
There isn't, the contacts in a circuit breaker are plated with silver.
What is thyristors?
A thyristor is a part of a alarm circuit you use it so the alarm stays on
What must you know before you change a circuit breaker?
Before you change a circuit breaker it has to be established that the breaker is at fault and not some other part of the circuit.
What do I do if there is no circuit breaker for outdoor light?
If you have a light that is not being powered through a circuit breaker or fuse, you should call a qualified electrician to remove this circuit from the panel's bus and install a circuit breaker for it. Without an overcurrent protective device (circuit breaker or fuse) you have a potential fire hazard.
What is the thyristor firing circuit?
The thyristor is basically used a switch in an AC circuit to control the amount of power fed to the load. To turn on this switch an "electric" pulse should be applied to the Gate terminal of the Thyristor. A circuit which supplies the "electric" pulse is called the firing circuit.
Can a thyristor work as a circuit breaker?
A thyristor is primarily a very fast "switch-on" device and is not designed to be used as a "switch-off" device.A circuit breaker is primarily a "switch-off" device which is used to automatically break the flow of current from a source to a load whenever the amount of current exceeds the rated current value of the breaker.So, because a thyristor does not, all by itself, "open" a circuit, a thyristor cannot be used to work as a circuit breaker.NotesCurrent flow through a thyristor can only stop if - external to it - the current flowing through it gets reduced to below its minimum holding current or, of course, to zero, as would happen either:i) if the load was disconnected from it by a separate circuit breaker that is wired into the circuit between the thyristor and the load;orii) if the source was disconnected from it by a separate circuit breaker that is wired into the circuit between the supply and the thyristor.Further notesA thyristor is designed to close or "make" a circuit whenever:a) an appropriate value of trigger voltage is put onto its gateand then only if:b) the current from the source to the load can flow through it in its "forward" direction.One way of ensuring it automatically disconnects the load from the source is to use an alternating current supply and always "trigger" the thyristor so that it turns on during each positive-going part of each ac cycle.Then, whenever the ac supply voltage returns to zero at the end of each positive half-cycle (after which it goes into the negative half-cycle) the thyristor will automatically break any further flow of current.By using other electronic circuitry to determine exactly when the gate is triggered (earlier or later in each positive-going part of each cycle) the amount of power supplied to the load can be controlled very accurately.That is why the main application for thyristors is to provide a precisely controlled way too use alternating currents to allow varying amounts of power to be supplied to electrical loads.
What does forced commutation mean?
The term "Forced commutation" is used when a thyristor is turned off using external components. If a thyristor is used in a DC circuit, when first turned on, it will stay on until the current goes to zero. To turn off the thyristor it is possible to use a Forced commutation circuit. The circuit creates a reverse voltage over the thyristor (and a small reverse current) for a short time, but long enough to turn off the thyristor. A simple circuit consist of a precharged capacitor and a switch (e.g. another thyristor) parallel to the thyristor. When the switch is closed, the current is supplied by the capacitor for a short while. This cause a reversed voltage over the thyristor, and the thyristor is turned off.
What is a Circuit breaker and explain type circuit breakers?
A circuit breaker is a switching device which can make,brake and carrying (or trip the circuit) that specified over currents for a small interval of time . There is a different types of Circuit Breaker's are there 1.According to their arc quenching media these are divided into 4 types a) Oil circuit breaker b) Air blast circuit breaker c) SF6 circuit breaker d) vacuum circuit breaker 2. According to their services the circuit breaker can be divided as a) Outdoor Circuit Breaker b) Indoor Breaker 3. According to the operating mechanism of circuit breaker they can be divided as a) Spring operated Circuit Breaker b) Pneumatic Circuit Breaker c) Hydrolic Circuit Breaker 4. According to the voltage level of installation these are divided into 3 types a) High Voltage Circuit Breaker b) Medium Voltage Circuit Breaker c) Low Voltage Circuit Breaker.
Is the circuit where is the is the circuit where is the circuit breaker for the?
The circuit breaker for the headlights is intergrated with the headlight switch.
How does a solid state circuit breaker works?
Recently a new technology "solid state' are applied to traditional circuit breaker. This technology has resulted in freeing circuit breaker from arcing and switch bounce, also offering higher reliability and longer lifetimes and a faster switching time.
What is circuit breaker handling trolley?
handling the circuit breaker
Is there an error if the upstream circuit breaker is 16A TP and the downstream circuit breaker is 16A TPN?
is there an error if the upstream circuit breaker is 16A TP and the downstream circuit breaker is 16A TPN?
What is a switch that opens a cuircut when too much current is flowing?
Where I'm from, it's called a "circuit breaker".A circuit breaker.
Is a circuit breaker a resistor?
No, a circuit breaker is a safety device that is used in a circuit to limit the amount of current in an overload or short circuit condition. The number on a breaker is the top end current that the breaker will handle before opening the circuit.
What is a non auto circuit breaker?
A non-auto circuit breaker is a circuit breaker with the trip element removed. Basically, it is a modified circuit breaker that is now a disconnect switch (glorified disconnect switch).
How does a Back to back thyristor work?
it works as a TRIAC
