Question 206Electricity & Electronics - 1st Asst/Chief

70% to pass

As shown in figure "A" of the illustration, under what conditions will the thyristor conduct? Illustration EL-0154

Diagram for USCG Electrical Chief: As shown in figure "A" of the illustration, under what conditions will the...
Awhen the anode is more positive than the cathode and when the gate is briefly pulsed with a voltage more positive than the cathode
Bwhen the anode is more negative than the cathode and when the gate is briefly pulsed with a voltage more positive than the cathode
Cwhen the anode is more positive than the cathode and when the gate is briefly pulsed with a voltage more negative than the cathode
Dwhen the anode is more negative than the cathode and when the gate is briefly pulsed with a voltage more negative than the cathode
AI Explanation

The correct answer is A) when the anode is more positive than the cathode and when the gate is briefly pulsed with a voltage more positive than the cathode. For a thyristor to conduct, two conditions must be met: 1) the anode must be more positive than the cathode, and 2) the gate must be briefly pulsed with a voltage more positive than the cathode. This triggers the thyristor to turn on and allow current to flow from the anode to the cathode. The other answer choices are incorrect because they describe conditions that would either prevent the thyristor from conducting (B and D) or require the gate to be pulsed with a negative voltage, which is not how a thyristor operates (C).

Want to practice with timed exams?

Download Coast Guard Exams for the full exam experience.

Get the App