What voltage level does a typical 28-volt DC aircraft electrical system aim to maintain, as controlled by the generator regulator?

What voltage level does a typical 28-volt DC aircraft electrical system aim to maintain, as controlled by the generator regulator?

• A. 12V
• B. 28V
• C. 115V
• D. 240V

Answer: (B)

A generator regulator keeps the DC bus at its nominal value, and in a typical aircraft with a 28-volt DC system that nominal value is 28 volts. The regulator adjusts generator output to hold the bus near 28 V as loads vary and engine speed changes. This setup allows avionics and accessories designed for 28 V to operate reliably while keeping wiring sizes and system design efficient. Other voltages listed aren’t the standard DC bus for this configuration: 12 V is more common in automotive or smaller gear, while 115 V and 240 V refer to AC or higher-voltage DC systems used in different aircraft power architectures.

A generator regulator keeps the DC bus at its nominal value, and in a typical aircraft with a 28-volt DC system that nominal value is 28 volts. The regulator adjusts generator output to hold the bus near 28 V as loads vary and engine speed changes. This setup allows avionics and accessories designed for 28 V to operate reliably while keeping wiring sizes and system design efficient. Other voltages listed aren’t the standard DC bus for this configuration: 12 V is more common in automotive or smaller gear, while 115 V and 240 V refer to AC or higher-voltage DC systems used in different aircraft power architectures.