How many positions does the AC voltage selector switch have?

How many positions does the AC voltage selector switch have?

• A. 3 positions
• B. 4 positions
• C. 2 positions
• D. 6 positions

Answer: (B)

The switch is used to pick which source powers the aircraft’s AC bus. In the Beechjet 400A, you have three possible power sources to select from—external power and two onboard generators—and you also need a way to isolate the AC system, which is the OFF position. That combination gives four distinct, detented positions: external power, generator 1, generator 2, and off. Having four positions ensures you can choose the correct source and also safely shut the system down when needed. A three-position setup wouldn’t provide an OFF state or would squeeze in an extra source without a proper way to isolate, while more than four adds unnecessary complexity.

The switch is used to pick which source powers the aircraft’s AC bus. In the Beechjet 400A, you have three possible power sources to select from—external power and two onboard generators—and you also need a way to isolate the AC system, which is the OFF position. That combination gives four distinct, detented positions: external power, generator 1, generator 2, and off. Having four positions ensures you can choose the correct source and also safely shut the system down when needed. A three-position setup wouldn’t provide an OFF state or would squeeze in an extra source without a proper way to isolate, while more than four adds unnecessary complexity.