Which power source powers the right igniter?

Which power source powers the right igniter?

• A. Main AC bus
• B. DC standby bus
• C. APU bus
• D. AC standby bus

Answer: (D)

The right igniter is designed to stay powered even if the normal electrical system has faults, so it is connected to an essential AC source. Igniters require AC power to generate the spark, and the AC standby bus is specifically intended to provide essential AC power to critical systems during abnormal conditions. That makes it the reliable source for the right igniter when starting the engine or when other power sources are unavailable. The main AC bus is the normal supply, but it can be lost or degraded; the DC standby bus provides DC power, which isn’t suitable for the AC ignition system; and the APU bus only powers systems when the APU is running. Therefore, the AC standby bus is the best fit for powering the right igniter.

The right igniter is designed to stay powered even if the normal electrical system has faults, so it is connected to an essential AC source. Igniters require AC power to generate the spark, and the AC standby bus is specifically intended to provide essential AC power to critical systems during abnormal conditions. That makes it the reliable source for the right igniter when starting the engine or when other power sources are unavailable. The main AC bus is the normal supply, but it can be lost or degraded; the DC standby bus provides DC power, which isn’t suitable for the AC ignition system; and the APU bus only powers systems when the APU is running. Therefore, the AC standby bus is the best fit for powering the right igniter.