# The applied sine voltage to SCR is Vm = 200 V and R = 10Ω.If gate trigger lags the ac supply by 120o, then average load current is

1.

2.

3.

4.

4 Explanation :
No Explanation available for this question

# A SCR has an anode supply of sine voltage 200 V rms., 50 Hz applied through a 100Ω resistor and fired at an angle of 60o. Assuming no voltage drop, the rms value of the output voltage is

1.  89.7 V

2.  126.7 V

3.  166.7 V

4.

4

126.7 V

Explanation :
No Explanation available for this question

# In the circuit shown in the figure, the maximum current in the main SCR can be (given I0 = 70.7)

1.  200 A

2.  170.7 A

3.  141.4 A

4.  70.7 A

4

170.7 A

Explanation :
No Explanation available for this question

# The circuit in the figure shows zener regulated dc power supply. The zener diode is ideal. The minimum value of RL down to which the output voltage remain constant, is

1.  27 Ω

2.  45 Ω

3.  15 Ω

4.  24 Ω

4

45 Ω

Explanation :
No Explanation available for this question

# A single-phase AC regulator with an inductance load has following details : Source voltage, 230 V, at a frequency of 50 Hz and ωL = 5 ohms. The control range of the firing angle is

1.

2.

3.

4.

4 Explanation :
No Explanation available for this question

# A single phase ac regulator fed from 50 Hz system supplies a load having resistance and inductance of 4.0 ohms and 12.73 mH respectively. The control range of firing angle is

1.  00 < α < 1800

2.  450 < α < 1800

3.  900 < α < 1800

4.  00 < α < 450

4

450 < α < 1800

Explanation :
No Explanation available for this question

# It is required to drive a dc shunt motor at different speeds in both the directions (forward and reverse) and also to brake it in both the directions. Which one of the following would you use

1.  A half-controlled thyristor bridge

2.  A full-controlled thyristor bridge

3.  A dual converter

4.   A diode bridge

4

A dual converter

Explanation :
No Explanation available for this question

# The frequency of ripple in the output voltage of a three-phase half controlled rectifier depends on

1.  firing angle

4.   supply frequency

4

supply frequency

Explanation :
No Explanation available for this question

# In the given circuit, if the resistance R is varied from 0 to ω, then

1.  phase remains constant.

2.  phase varies from 0 to ± 900

3.  magnitude is constant and phase varies from 0 to 1800

4.  phase of the circuit is given by 2 tan-1

4

phase of the circuit is given by 2 tan-1 Explanation :
No Explanation available for this question

1.  100 S

2.  100s

3.  1 ms

4.  50 S

4