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The device whose symbol is seen to be Two SCR’s Inverse parallel connected is:

The device whose symbol is seen to be Two SCR’s Inverse parallel connected is: Correct Answer Triac switch

TRIAC:

  • The TRIAC is a 3-terminal semiconductor device and may be considered equivalent to two SCRs connected in antiparallel or Inverse paralle
  • TRIAC are bidirectional devices. 
  • It is ideal for operation utilizing AC power for switching purposes (operated at power frequency) 
  • It can control current flow for both halves in an alternating current cycle.

 

Additional Information

Silicon Unilateral Switch:

  • It is a unilateral four-layer silicon diode with two electrodes.
  • It is a member of a thyristor family.
  • And available with a current rating of about 200 mA, and reverse voltage blocking rating of about 30 V, switching voltage rating of 6 to 10 V.
  • It resembles the SCR in construction which has anode and cathode.

Related Questions

Consider the following statements: 1. In a silicon controlled rectifier (SCR), if the cathode gate is reverse-biased, then the SCR cannot fire at all. 2. The turn-on time of an SCR increases with temperature. 3. After an SCR is turned on, it can be made to turn off again by reverse biasing the gate. 4. Gate recovery time is the minimum time that the anode voltage must be maintained below holding voltage VH to turn off the SCR. Which of these statements are correct?
A 220 1-ϕ, 220 Ω  resistor is connected in series with the gate of an SCR as shown in the given figure. The gate current required to fire the SCR is 7 mA. what is the input voltage (Vin) required to fire the SCR?
A voltage source Vs = Vm sinωt is connected in series with a resistance R and an SCR. At some firing angle delay of α a positive gate pulse is applied to the SCR which turns on the SCR. Considering ideal conditions, at the instant α the voltage at the resistor terminals Vo
Two centrifugal pumps P and R are available for use in a pipe flow system and their head-discharge characteristics are as follows. Pump P Pump R Discharge (cumecs) Head (m) Discharge (cumecs) Head (m) 0 40 0 45 0.12 35 0.14 40 0.2 28 0.24 35 0.3 18 0.3 28   The following statements (S1, S2, and S3) pertain to the head and discharge values during actual operation. Neglect losses in the system. Which of the following statements are correct? S1: When the two pumps P and R are connected in parallel, the discharge is 0.36 cumecs corresponding to a head of 35 m. S2: When the two pumps P and R are connected in parallel, the discharge is 0.36 cumecs corresponding to a head of 70 m. S3: When the two pumps P and R are connected in series, the discharge is 0.3 cumecs corresponding to a head of 46 m.
When a 1-phase transformer is connected in parallel, there are four conditions for proper parallel operation, but when two or 3-phase transformer paralleling is done, there are two additional points along with those four conditions applied for 1-phase. Statement 1 - The phase sequence must be the same. Statement 2 - The phase shift between primary and secondary voltages must be the same for all transformers connected in parallel. From the above two Statements (s), which is/are the correct conditions in this regard?
At a 33kV 50 Hz to a bus a load of 35 MW is connected. To improve the power factor to unity a synchronous phase modifier is connected taking 5 MW. If the SPM is represented as delta connected impedance, where in each phase we have capacitor connected parallel to resistance forming RC parallel network, then the value of this resistance is ___________
At a 33kV 50 Hz to a bus a load of 35 MW is connected. To improve the power factor to unity a synchronous phase modifier is connected taking 5 MW. If the SPM is represented as delta connected impedance, where in each phase we have capacitor connected parallel to resistance forming RC parallel network, then the value of this capacitance is __________
Latching current for an SCR is 100 mA, DC source of 200 V is also connected from the SCR to the L load. Compute the minimum width of the gate pulse required to turn on the device. Take L = 0.2 H.
Latching current for an SCR is 100 mA, a dc source of 200 V is also connected to the SCR which is supplying an R-L load. Compute the minimum width of the gate pulse required to turn on the device. Take L = 0.2 H & R = 20 ohm both in series.
A single-phase voltage controller, using one SCR in anti parallel with a diode, feeds a load R and Vs = 230 V. For a firing angel of 90° for the SCR, the PMMC voltage connected across R would read