Wiring Fundamentals: DC and AC
DC and AC
01.10
00:00 | - The terms DC and AC are short for direct current, and alternating current. |
00:05 | What these terms refer to is the direction the current in our circuit is flowing. |
00:09 | In a DC circuit, the current direction is always the same. |
00:12 | The amount of current flowing might change, but the direction will always be constant. |
00:17 | In an AC circuit, both the amount of current flowing and the direction of flow can change or alternate. |
00:23 | From the previous modules, we have an understanding of how current will flow in response to an applied voltage. |
00:29 | Much like the water in our plumbing pipe will flow a higher pressure to a lower pressure, a current will flow from a high voltage to a low voltage. |
00:38 | If we swap which ends of our wire are connected to the battery positive and negative, the current will flow through the wire in the other direction. |
00:45 | This sounds simple, and it is, that's really all there is to it. |
00:49 | If we reverse the direction or polarity our voltage is applied in, the resulting current flow will also change direction. |
00:56 | The large majority of automotive electrical systems are DC. |
00:59 | But it's worth having a brief understanding of AC circuits. |
01:02 | Particularly later on when we come to discussing engine speed sensors. |