18 Volts between earth and neutral: is it normal?

I have a Power Plant P20.
I noticed with a voltmeter that there are 18 Volts between the neutral and earth pole after the P20, but I have only 2 Volts between neutral and earth in the wall plug, before the P20.
The P20 is working fine but I wonder if this high value is normal? Why does the voltage rise between neutral and earth pole after passing the p20?

Where are you measuring the 18V?

Have you tried a different cord?

Definitely not normal. Did you measure your outlet with the p20 on?

Yes, the measure is made with the p20 switched on.

The output is precise ar 230 Volt between hot and neutral poles.

What part of the world are you in? As ground / neutral system can work very differently where you live. Eg US has ground near the house (I believe) UK takes earth all the way back to the substation where it is connected to ground along with neutral (I think)

I live in Italy.
I specified that before the P20 the voltage difference between neutral and earth is 2 Volt and after the P20 is 18 Volts.
Is it normal? I’m asking to the members of this forum what is their experience?
Thank you

I don’t have the answer, but it would only ever meant be the same if the P20 connected input & output ground and input / output neutrals together and just regenerated the live, which to me sounds unlikely.

Maybe @jamesh can help?

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This one is ok. What about neutral - ground measurement with the p20 turned on?

I am not certain what the measurement is showing and what relevance it is but I can share with you that the P20 does not affect neutral at all. The regenerator is on the hot side only and the neutral is not impacted. So this is odd. What is the incoming and outgoing voltage?

Yes, this sound right and more important is that there isn’t much important about the distance between the two.

So, there you go. Going by what Paul says, something is wrong with your P20 if your measurements are correct.

Happy Cake Day, @chris5 !

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Hi @Paul , I thought there was a difference. In UK. Neutral wire is connected to Earth (at the substation) In the US Neutral is not connected to Earth.

In the US, the neutral is connected to earth ground at any separately derived service (ie service entrance, secondary of most transformers, some generators, etc) through a bonding jumper.


Just to clarify, a “service entrance” includes the electric panel/breaker box in a U.S. house.

Ok. Thanks. There is some important difference, that my collage lecturer told me 40 years ago, but I can’t quite remember what, very frustrating :wink: