Should the AC be turned off before shutting down the engine?

[GageRose]

It is necessary to turn off the AC. Here is an introduction about AC: 1. Introduction: Alternating current (AC) refers to an electric current whose direction changes periodically over time, with an average current of zero over one cycle. Unlike direct current (DC), its direction changes over time, while DC does not have periodic changes. Typically, the waveform of AC is a sine curve. AC can effectively transmit electric power. However, in practice, other waveforms are also used, such as triangular waves and square waves. The mains electricity used in daily life is AC with a sinusoidal waveform. 2. Applications: Generators, power transmission, transformers.