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If the RC firing circuit used for firing an SCR is to be used to fire a TRIAC then
The TRIAC is a bidirectional SCR, hence it will need gating in both the directions. This can be achieved by replacing the diode by a DIAC (bidirectional diode).
In the thyristor gating circuit, the supply to the pulse amplifier is provided by the
Isolation transformer provides the supply to the amplifier and also provides the necessary isolation for the load and triggering circuit.
In the thyristor gating circuit, the ZCD is used to
It is used to convert the AC synchronizing input voltage into ramp voltage & synchronizes it with the zero crossing of the AC supply.
The firing-angle delay is
If Ec is lowered the firing angle decreases & vice-verse.
The pulse gating is not suitable of
It is not suitable of RL load because initiation of SCR conduction is not well defined in these types of loads.
In case of a cosine firing scheme, __________ is used to get a cosine wave
The Sync. Transformer is connected to a integrator to obtain a cosine-wave.
If the gating circuits generator negative pulses, then those can be removed by using
The clippers can be used to clip the negative part
The improved version of the UJT oscillator triggering circuit is the
The ramp & pedal triggering is the improved version of the UJT oscillator triggering circuit.
RB1 = 3 kΩ & RB2 = 6 kΩ. Find the intrinsic stand-off ratio (η) of the UJT.
η = RB1/(RB1+RB1).
The decaying factor in the wave shape of the output pulses from the pulse transformer is its
L is the decaying factor in the waveform which emerge from the PT.