Plain English Meaning

A small electronic box that turns the steady D.C. power from the aircraft's battery into the alternating-current power that some instruments need to run. It does this using electronic chips rather than spinning parts.

Full Definition

An electronic device with no moving parts that converts direct current (D.C.) from the aircraft battery or generator into alternating current (A.C.) at the voltage and frequency required by certain aircraft instruments and equipment. It uses semiconductor components such as transistors to switch the D.C. supply rapidly, producing an A.C. output — typically 115 volts at 400 hertz for aviation use.

Context Anchor

Seen in aircraft electrical-system discussions, especially where D.C. aircraft power must supply instruments or equipment that need A.C. power.