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Faerie (October 23, 2017, 04:53:19 AM):

Yeah, but verily, remember that she can smite thee too. In fact, you sound like you're a bit smitten. :-)
Im in awe of seeping intelligence... I often imagine whilst conversing with a uniqely intelligent person that their heads explode and the brains splatter across the walls. How do they hold that much knowledge in the confines of a humble (or perhaps not so humble) package of grey matter encased by bone?
Bit crude, but thats my brain!
Tweefo (October 23, 2017, 07:45:10 AM):
Thank you all, There is now a glimmer of light in the back of my cave. 8)
SKEPRat (October 24, 2017, 13:01:22 PM):
Hi Mefiante

The 0.168 Volt or similar on a modern electronic digital display multimeter is normal for that instrument. This is why aspirant electricians are first taught how to use and interpret a digital multimeter before using it. If you had used an old moving coil type multimeter you would have seen 0 Volt, as the above 220V scale would never allow you to read 0.172 Volt or similar.

I can only assume that the measuring points were incorrect on the points you did not get the required results on or your technique was incorrect. Get any electrician to measure those points as I stated and you will get the results I stated.

There is a vast difference in results if the experiment is performed incorrectly.

You can be shocked by inserting a nail into the neutral socket with the plug switched off. My exact point in answering this post. The neutral is always at a 220V potential above earth if the power is supplied or if you earth yourself in any way. Eg. Standing in a pool of water or touching a brass window handle on a steel window frame. Or touching the earth socket on a plug. The exact reason the SA and British plugs have a barrier to inserting anything into the sockets. Never assume your earth leakage protection is working either.

Also don't assume the wiring in your plug is correct. A fatal mistake for any electrician. The colour codes may be swapped. Try the experiment assuming the codes are incorrect. Never take anything at face value with electricity - always assume that it is deadly and check. The erroneous points 2 and 6 indicate incorrectly coded wiring or swapped live and neutral connection points.

Another fact is that a meter never measures the highest value of the Voltage in the circuit. It measures the Root Mean Squared (RMS) voltage which is 0.707 of the peak voltage of the sine wave.
Mefiante (October 24, 2017, 15:46:12 PM):
I can only assume that the measuring points were incorrect on the points you did not get the required results on or your technique was incorrect. Get any electrician to measure those points as I stated and you will get the results I stated.
Not so, as all four other readings agree, near enough, with what both your protocol and I said they should be.

The neutral is always at a 220V potential above earth if the power is supplied or if you earth yourself in any way. Eg. Standing in a pool of water or touching a brass window handle on a steel window frame. Or touching the earth socket on a plug.
Clearly, this isn’t true, since in both cases we measured a voltage of less than 0.3V between E and N.

Also don't assume the wiring in your plug is correct.
Agreed—which is why we took all of the other measurements as well and reported them here.

The erroneous points 2 and 6 indicate incorrectly coded wiring or swapped live and neutral connection points.
Again, not true, since each of the other four measurements is in agreement with what we both claim they should be.

Another fact is that a meter never measures the highest value of the Voltage in the circuit. It measures the Root Mean Squared (RMS) voltage which is 0.707 of the peak voltage of the sine wave.
I understand RMS quite well in the context of wave phenomena, among which are AC measurements and voltage/current specifications: You integrate the square of the voltage amplitude over a full wave period, divide by the length of that period, and take the square root of the result. For a sinusoidal wave as is AC, this works out at 1/√2 of the magnitude of the peak amplitude, and 1/√2 ≈ 0.707. If you have three-phase power in your home, the RMS voltage between any two of the three phases is nominally 380V, whereas it’s 220V between any one phase and neutral (380/220 is near enough a factor of √3, which also isn’t a coincidence). But this fact alone already seriously challenges the claim that “The neutral is always at a 220V potential above earth if the power is supplied…” since the three phases are shifted by 120° relative to each other.

Here’s a pair of photos showing what was measured at a different plug in respect of the two contested readings. The other four readings were, again, in agreement with what we saw before:





In each case, you can see whether the plug is switched on or off, which poles are being measured, and the reading on the multimeter’s display. It will be noted that the readings are in “mV” or millivolts; in volts, that’s the reading divided by 1,000.

Consequently, I still remain at the point where I began.

My suggestion in order to put this matter to rest is that some other forum regular performs these same measurements and then reports their findings here independently.

Will someone please step up to the plug? I mean “plate.” Anyone? Please?

'Luthon64
BoogieMonster (October 24, 2017, 16:23:51 PM):
Will someone please step up to the plug? I mean “plate.” Anyone? Please?

I shall. I was contemplating doing it already as ...

You can be shocked by [...] Standing in a pool of water or touching a brass window handle on a steel window frame.

... sounds ludicrous. As even wikipedia states.

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