Answer / phani chavali

Thyristor is a siliconcontrolled rectifier.It is a 3
terminal, 4 layer device.The names of 3 terminals are
anode,cathode and gate.It is mainly operated under 3 modes
namely forward conducting mode,forward blocking
mode,reverse blocking mode.Thyristor is conducting only
under the forward conducting mode.We can make thyristor
conducting by applying gate triggering means by giving
certain gate voltage.

Answer / guest

A thyristor is a semiconductor device which acts as a
switch. However, when switched on it can only pass current
in one direction. It is in fact a switchable diode
sometimes known as a silicon controlled rectifier. To
switch alternating current two devices are connected in
inverse parallel.

Each device is turned on at the appropriate time by a
trigger pulse applied to the gate and the device will
remain on until the instantaneous load current through it
drops to zero.

The trigger pulses are generated by a driver - which times
the pulses to ensure the thyristor unit output is a
function of the input demand signal (e.g. from a
controller) in the selected Firing Mode.

Eurotherm thyristor units incorporate the thyristor
devices, together with the driver and the heatsink which
dissipates the heat generated by the thyristor devices.
Many units include internal high speed fuses to protect the
thyristors from high overload currents. The benefits of
thyristor units are numerous. They offer a reliable long
term alternative to electromechanical devices reducing the
necessity for ongoing maintenance.

Thyristor units are particularly cost effective for fast
systems, for complex loads involving transformers and/or
heaters whose resistance changes with temperature or time

Answer / dinesh kumar

1.A thyristor/SCR is semiconductor device
2.It has 3 terminals and 4 layers (PNPN)
3.Thyristor will conduct only in forward bias.
4. By applying firing pulse to gate scr is controlled
5.scr can be used as
a. switiching devices
b. Convert Ac to Dc (converter)
c. Inverteer

Answer / vijaymuthu

thyristor is semicontor diode

Answer / pradeep

thyristor is also know as 'scr'.it is a a power electronic
device worked as transistor.Very small current flow through
the gate.When triggered current flow from anode to cathode
in one direction,so it acts as a switch.

Answer / bala and guna

thyristor is a power electronic device which is used as a
switching device.which on state voltage drop is very less

Answer / dolphin

a thyristor is a semiconductor device which have
three or more junctions like scr diac triac etc

Answer / baswaraj

Thyristor is also called SCR, stands for Semi Conductor
Rectifier. It is basically a four layer semi conductor
device like a transistor that is a three layer
semiconductor device.

It is generally used as a switch in the power circuit as it
can only be turned on by providing a pulse at its one of
the sandwitched layer called Gate, and the pulse is also
called firing pulse or triggring pulse. The main advantage
of this over the transistor is the it can be used into the
power circuits.

Answer / apratim ambade

thyristor is diode with switch,which can be switched at any
desired instant of time by applying triggering pulse

Answer / amirtha

thyristor include scr &triac .... these are mainly used for
switchingand controlling....it is used in relay circuits

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