Definition
The maximum instantaneous value of current reached during one cycle of an alternating current waveform, measured from the zero reference line to the highest point of the wave.
Plain English
The highest amount of current the wave reaches at its tallest point during a single cycle.
Context Anchor
Seen in aircraft electrical system study, especially when discussing alternating-current power, generators, and component limits.
Derivation
From 'peak' (the highest point of something) and 'current' (the flow of electricity). The term simply describes the highest point reached by the flowing current during its cycle.
Why Pilots Care
Components in an AC system must be rated to handle the peak current, not just the average value, or they can fail. Knowing the difference between peak and average values matters when interpreting electrical specifications.
Analogy
Think of a wave on water. The peak is the very top of the wave, not the whole wave and not its average height.
Intuition Check
Do not read “peak” as the normal steady value. Peak current is only the highest instant of electrical flow. Also, “current” here means electrical flow, not “current” as in present time.
Example Sentence 1
The peak current in the AC circuit was about 1.4 times the effective current, as expected for a sine wave.
Example Sentence 2
During the test the technician recorded the peak current drawn by the starter motor.