What is a typical advantage of using a 2-out-of-3 voting scheme over 2-out-of-2?

What is a typical advantage of using a 2-out-of-3 voting scheme over 2-out-of-2?

• A. Requires more sensors, which increases complexity.
• B. Maintains operation if one sensor fails while tolerating one sensor fault.
• C. Uses fewer sensors than 2oo2.
• D. Eliminates need for alarm signaling.

Answer: (B)

A 2-out-of-3 voting scheme gains fault tolerance by using a majority decision from three independent sensors. Here, the output is triggered if at least two sensors agree. That means if one sensor fails or starts giving a faulty reading, the remaining two sensors still provide the correct result, so the system continues to operate safely. With only two sensors, a single fault can skew the outcome or force a shutdown because there’s no majority to override the bad signal. So the key advantage is continued operation in the presence of one faulty or failed sensor. The other choices describe adding more complexity, using fewer sensors, or eliminating alarms, none of which capture this reliability benefit.

A 2-out-of-3 voting scheme gains fault tolerance by using a majority decision from three independent sensors. Here, the output is triggered if at least two sensors agree. That means if one sensor fails or starts giving a faulty reading, the remaining two sensors still provide the correct result, so the system continues to operate safely. With only two sensors, a single fault can skew the outcome or force a shutdown because there’s no majority to override the bad signal. So the key advantage is continued operation in the presence of one faulty or failed sensor. The other choices describe adding more complexity, using fewer sensors, or eliminating alarms, none of which capture this reliability benefit.