I'm plugging in my power switch, and it doesn't have positive and negative labeled .
The cords are different patterns, so is anyone aware?
41 Answer
The power switch on the front of a PC case does not care about + or - since it either conducts electricity, or it doesn't. It carries very little current and is low voltage (5V).
Your LED uses Direct Current (DC) so there is a + and a -. Plugging an LED in the wrong way can fry it, so it's marked. LEDs also work on much less voltage, so connecting wall power and an LED is bad news and not recommended.
The above is universal to all PCs all over the world. Now, here's what changes depending on where you are:
In the US, a two prong wall power cord ('Mains' as they say in Britland) is 120 volt Alternating Current ('AC'). See Type A.
There is no + or - because the current alternates between positive and neutral. The left slot is slightly larger than the right. The left slot is called "neutral," the right slot is called "hot".
Washing machines, stoves, and heavy power equipment use three-phase 208V AC with a positive, a neutral, and a negative.
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