Which DC Bus is named to carry battery power directly from the main source?

Which DC Bus is named to carry battery power directly from the main source?

• A. DC Battery Bus
• B. DC Main Battery Direct Bus
• C. DC APU Battery Direct Bus
• D. DC Emergency Bus

Answer: (B)

In aircraft electrical systems, bus names indicate exactly where their power comes from and how it reaches the bus. The DC Main Battery Direct Bus is the one that carries battery power straight from the primary power source. The word “Main” shows it’s tied to the main power source, and “Direct” means the feed to this bus goes along a direct path from that source, without going through additional distribution steps. This setup allows battery power to be delivered to essential DC circuits quickly whenever the main source is supplying power or when battery power is needed without delay. The other options describe feeds from different sources or different purposes (APU power, a general battery bus, or an emergency-only bus), so they aren’t designated as the direct main-battery route.

In aircraft electrical systems, bus names indicate exactly where their power comes from and how it reaches the bus. The DC Main Battery Direct Bus is the one that carries battery power straight from the primary power source. The word “Main” shows it’s tied to the main power source, and “Direct” means the feed to this bus goes along a direct path from that source, without going through additional distribution steps. This setup allows battery power to be delivered to essential DC circuits quickly whenever the main source is supplying power or when battery power is needed without delay.

The other options describe feeds from different sources or different purposes (APU power, a general battery bus, or an emergency-only bus), so they aren’t designated as the direct main-battery route.