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Yeah, I know, it is such an old question, so many discussions on this topic, but I cannot realy find an exact answer in the Internet.

I live in Ukraine, where we have 230V AC outlets, as in most European countries. I know that touching a neutral wire when there is no load is comletely safe, but what if I touch the bare part of a wire wehen something is plugged in and working like this Cyberpunk-2077 meme image shows? Some people say that touching a neutral in this case will lead to the same result as touching the hot wire because it is AC and current path changes 100 times a second (we have 50 Hz.) Others say that the neutral wire will never shock you because it is firmly grounded at the transformer. Who is right?

(image source: https://gaming.ebaumsworld.com/pictures/29-cyberpunk-2077-memes-that-are-pure-future/86042405/)

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  • \$\begingroup\$ How can you tell it is neutral and not some wiring mistake that caused it to be live due to an incompetent electrician? \$\endgroup\$
    – Andy aka
    Nov 8, 2023 at 10:42
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    \$\begingroup\$ I know that touching a neutral wire when there is no load - what difference does that make? 230 V is less aggressive and more likely to sit down for a coffee? \$\endgroup\$
    – MiNiMe
    Nov 8, 2023 at 11:05

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Some people say that touching a neutral in this case will lead to the same result as touching the hot wire because it is AC and current path changes 100 times a second (we have 50 Hz.) Others say that the neutral wire will never shock you because it is firmly grounded at the transformer. Who is right?

Neither.

Neutral is (somewhat) safe to touch when everything is operating correctly. As you noted, it is connected to ground so there shouldn't be any voltage difference between neutral and ground.

If there is a very heavy load (a lot of current flowing) and the neutral connection has a high resistance, then there can be a fairly high voltage on the neutral. High enough to hurt, maybe high enough to kill.

If the neutral is broken, then supposedly safe neutral will be connected to the hot through appliances connected to the outlets. That will be the full line voltage, certainly enough to kill.

In normal use, nothing (should) happen to you if you touch neutral. Something could be wired wrong or broken in the house, making it unsafe to touch the neutral.


Along with all that is also the fact that houses may be incorrectly wired. A wire that is color coded neutral (blue) may in fact actually be hot.

Normal practice before working on home electrical stuff is to check that the power is on at the outlet (using your meter or other electrical test device such as an electrician's screwdriver with a neon bulb) or whatever part you are working on. This proves to you that the wiring is live. It also shows you that your tools are working properly. At the same time, you can check live, neutral, and ground to be sure what voltage level is really present.

Once you know everything is powered, how it is wired, and that your tools are OK, you can switch off the power.

With the power off, check to see that your meter or test device truly shows that there is no voltage present on any of the lines you need to work on.

If this second test shows the power is truly off, then you intentionally connect the hot with the neutral. If things are really off, nothing will happen - else you get scary sparks and the circuit breaker trips.

When the power is really, truly, off you can get to work doing things that involve actually touching the wires.

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  • \$\begingroup\$ no, neutral is not always connected to ground. see below. \$\endgroup\$
    – danmcb
    Nov 8, 2023 at 13:45
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    \$\begingroup\$ Every place I've heard of has neutral connected to ground. I think it would be good for you to show some wiring standard that says that houses may be connected without grounding the neutral. The only thing that makes neutral different from hot is that neutral is connected to ground. If it ain't connected to ground, it ain't neutral. \$\endgroup\$
    – JRE
    Nov 8, 2023 at 13:56
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For being shocked, you should allow enough current to flow through your body from the touch point (neutral wire and your finger) to the point where you are standing on (earth). Since your body will act as a resistance between these points, there must be a voltage for a current to flow i.e. if that voltage is high enough then there's going to be a high enough current to shock (or even kill) you. If there's no potential difference between these points then you won't get shocked... in theory.

For the distribution systems (such as TN-E, TN-C etc, except IT) the Neutral is bonded to the Earth at the transformer/generator side of the distribution network. So it's supposed to be at ground potential.

However...

Distribution network wires are not short and the connection between your house's neutral and the transformer/generator around your area may not be good enough so we can't assume that there will always be virtually zero potential difference between the neutral and the earth. That potential difference can be high enough to shock you.

So in practice, it's not always safe to touch the Neutral wire.

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It is absolutely NOT safe. In SOME countries the neutral goes to a local ground, but that may be some distance away and there can still be some 50V rms or so on that pole, which is still enough to induce a fatal current in the body - depending on the health of the person and the current path through the body.

Moreover, the N pole is actively driven in many European countries and is thus just as lethal as the L pole.

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    \$\begingroup\$ This is the first time when I hear N pole being actively driven in many European countries. Can you give any examples where exactly? The only exception where N pole really is actively driven that I know of are UK construction sites, where tools use 120VAC but in split phase so 60VAC on Neutral and Live. \$\endgroup\$
    – Justme
    Nov 8, 2023 at 12:06
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    \$\begingroup\$ Historical reasons I think. I've heard that some houses here in Belgium have three phases at 230V coming in, your lighting circuit might use poles A and B while the power sockets are on B and C. You have to be careful, you cannot assume anything. It caused me some surprise when I discovered, but it is so. \$\endgroup\$
    – danmcb
    Nov 8, 2023 at 13:27
  • \$\begingroup\$ the first time I had cause to apply a meter to the supply terminals here I was most perturbed to find two wires with 230V to ground - "what? there are two live wires?" yes there are. \$\endgroup\$
    – danmcb
    Nov 8, 2023 at 13:37
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    \$\begingroup\$ @danmcb Three phase 230V is common and even default depending on where you live. There are three 230VAC phases to Neutral and PE, and 400V between phases. Your 230V lights or sockets would not be between two phases or your single phase would be 132V. And Netherlands is a 230V/400V country. I do wonder what you were measuring if both terminals were at 230VAC. \$\endgroup\$
    – Justme
    Nov 8, 2023 at 14:03
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You can touch whatever you want: As long as you are floating, no current will flow through you. See birds, for example.

If you are touching other things, like door frames, other appliances, or even just a moist ground, touching L or N are equally hazardous.

Never trust a random (potentially colorblind, or tired) person who installed your wiring with your life.

Instead do consider every wire of mains distribution (that is not PE) to be a live wire.

If you must touch this wire, with no chance to turn power off, you better make damn sure, that you are floating.

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