If it’s AC current neutral can be live too and live can be neutral too. Isn’t it?
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It’s live, not positive.
Electric circuits work by something pushing or pulling the electricity. In DC, it’s getting pushed in a certain direction. In AC, it’s getting pushed one way then pulled the other in rapid succession. But it’s still being driven from the same place!
In other words, the “live” wire is the one actually trying to shift electrons. The neutral wire is just there so the electrons have somewhere to go or something to get pulled from. If you connect live to the ground (either directly or via…you) then the live wire can still drive the current.
Live is called live because there is voltage on that line.
If you connect the neutral wire to ground nothing happens, because in an open circuit there is no voltage on neutral. If you connect live to ground you will get a short circuit current flowing, because there is voltage on that line.
In other words, if you touch a neutral wire of an open circuit you won’t get shocked. If you touch a live wire, you **will**
>If it’s AC current neutral can be live too and live can be neutral too. Isn’t it?
It’s an easy misunderstanding but AC does not mean that there is a constant change of positive voltage between two wires, i.e. wire one flickeres up to 240V wile wire two surges down to 0 and vice versa.
It means that the live wire rapidly changes from a positive to a negative voltage relative to the neutral wire.
No. Neutral is always 0V, typically referenced to ground and that’s why it’s safe to touch. The live wire alternates between 240 and -240V and that’s why it’s called live.
That’s also why you have to respect polarity in things like ac motors otherwise they run in reverse.
First some background you probably already know: In most countries, home electrical items run on two wires. Even if you have a plug with three prongs, the electricity is just flowing through two of them. The third prong (usually called ground or earth) is just there for added safety and doesn’t normally carry any electricity.
The two wires carrying the electricity are often called the live (or hot) and the neutral wires. In a power grid, the neutral wire is literally connected to the earth somewhere (probably in many places). Since the neutral wire is connected to the earth, it has zero voltage when measured using the earth as the reference. Thus, all the voltage change is happening only on the live wire.
This does not have to be the case. If you have a portable generator and run it without connecting it to ground, then the voltage is “floating”. In this situation — where no part of the generator (or the load it is running) is connected to ground — it is not really correct to say one wire is live and the other neutral. It’s not until a ground connection is made that you really get this distinction.
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