Question

In the complementary commutation circuit shown below, if the turn-off time of SCR is 30 $\mu sec$ and safety margin is 2,then the value of capacitor required for proper commutation will be ______.

• A. 124.52 nF
• B. 1442.7 nF
• C. 1154.1 nF
• D. 4.82 nF

Answer 1

The correct option is B 1442.7 nF

The minimum value of capacitor for proper commutation,

$C=\frac{SF\times t_{c1}}{R_{2}ln2}=\frac{2\times 30\times {10}^{-6}}{60\times ln2}$

= 1442.7 nF