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No difference only the voltage and frequency have changed

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A

In Reply to: RE: what's the difference between 'hot' and 'neutral' in 240v AC power? posted by Tom Schuman on June 19, 2011 at 18:52:26

I took a quick look at NZ electrical codes and found a few things that migh help.

Wiring colors are Brown=Hot Blue=Neutral Green/yellow=Earth

Older wiring and cords might have Red=Hot Black=Neutral Green=Earth

From the drawings the A or P terminal is HOT and should be on the left.

You can always determine the hot neutral with a volt meter by measuring from the earth terminal. The hot should read 230V to ground and the neutral should read zero.
http://www.energysafety.govt.nz/upload/33458/ecp51v18.pdf (Open in New Window)

Follow Ups:

RE: No difference only the voltage and frequency have changed - coffee-phil 15:47:55 09/09/11 (1)
I can only speek with any sort of authority about US power. I assume it is similar in New Zealand. In the US most residences get 120 Volts for lighting and most appliances, and 240 Volts for large loads such as clothes dryers, ovens, and air conditioning compressors.
The house is fed from the secondary winding of a transformer. This winding is center tapped with 240 volts from end to end. From either end to the center is 120 volts. The center is connected to Earth. All three leads are fed to the house. The center lead is called neutral because it is connected to earth. This means that there is little (ideally 0) voltage between it and earth. The other leads are 120 volts from the neutral and are called hot. If you were to touch one of them and something connected to earth you would agree that the name is appropriate. The 120 volt loads in the house are pretty much equally divided between the two hots and neutral. 240 Volt loads are connected between the two "hot" leads. Knowing which lead is hot is useful for safety.
Since you don't have 120 volts, I'm guessing that one side of a 240 volt winding is connected to earth and called neutral and the other side is hot. Again this is useful for safety.
Phil

Edits: 09/09/11
- RE: No difference only the voltage and frequency have changed - Mushroom Soup 11:07:03 09/29/12 (0)
  That assumes that they have the same line voltages that the US has, which I don't think you can assume.
RE: No difference only the voltage and frequency have changed - Tom Schuman 00:19:29 06/22/11 (1)
Thanks for the link. In NZ, the 'live' lead is on the left as you look at the wall plug.
My question was more what difference it makes to have equipment plugged in the 'wrong' way around...it looks like I should pay attention to the phase in my installation even when using European gear.

Out comes the multimeter to determine the phase of my equipment. I think the computers all have switch mode supplies where I suspect it doesn't matter at all.

Thanks and cheers.
- RE: No difference only the voltage and frequency have changed - jea48 07:08:38 06/22/11 (0)
  > >
  - http://www.boundforsound.com/tweak.htm (Open in New Window)

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