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An SCR HWR is applied a Sine wave voltage. If its firing angle is 45°, what is the value of the maximum conduction angle possible if load is purely resistive in nature? Identify from the options given below. 

An SCR HWR is applied a Sine wave voltage. If its firing angle is 45°, what is the value of the maximum conduction angle possible if load is purely resistive in nature? Identify from the options given below.  Correct Answer 135°

Conduction angle :

The number of degree’s in a half cycle for which SCR is turned ON, is known as Conduction angle (γT). 

Single Phase Half Controlled Rectifier:

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The firing angle α = 450

From the above waveform, conduction angle (γT) = π - α

= π – 450 = 1350

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