An electrical one way valve-it is a semiconductor device that allows electricity to flow in one direction, but not the other. The symbol is:

Symbol for a diode
Diode picture and symbol. On the left, we see a picture of a diode, with the Anode and Cathode marked, as well as the symbol for a diode. This diode will conduct current in the direction of the triangle in the symbol.


One common use in plant vehicles is in the rectifier of the alternator. The rectifier converts the alternating current produced by the alternator into direct current that can be used by the plant vehicle electrical system.

There are many variations on diodes: Check out LEDs and Zener Diodes.

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