Correct Bridging (Resetting) Socket Methods: Comparing Two Approaches with Expert Insights

Hello.
How correctly should bridging (zeroing) be done and why and not otherwise? I asked my grandfather, he said it doesn't matter, but I prefer to be sure, because there are two ways.
http://www.editer.pl/publikuj/16352a78436d568560f210e4bf229e31_1.jpg/
I am throwing in the link, because it will not be possible to add a photo, because an error pops up.

It would be safest to tighten the earthing (PE conductor) separately, but if it is impossible, connect N first with the pin, then with the N socket. If the N from the socket burns, then it will still be N on the ground. However, when the N from the socket gets hot, and there will be a connection of the N socket to ground,
then we have full voltage on the housing. It will also be when the N wire between the socket and the power supply gets hot. The device will not work, and there will be full voltage on the metal grounded parts. Therefore, in old installations made with small cross-section cables, I would not risk such connections.
The earth-fault protection will also not work in such a system.

Moderated By kkas12:

The N-conductor must never and under no circumstances be connected anywhere with the protective contact of the sockets or with accessible conductive parts.
"Help" I go back.

Theoretically there is a difference - it is better to connect the wire first to the grounding "pin" and then to the N terminal. Why? Because in the case of a poor connection of the wire / bad terminal in the socket, etc. the "PEN" wire will burn at the N contact. If in such a situation a bridge between PE and N is left, then a phase potential will appear on the housing of the device due to the resistance of the connected device.

Moderated By kkas12:

Not better, only obligatory first to the protective contact. And not N or PEN, but the zero wire.
"Help" I go back.

I am so shy to ask the advisers of the above posts if there is a known network system
power supply? since you give advice so definitely.

Loker wrote:

phase potential will appear.

What happens then?

zbychmg wrote:

and there will be full mains voltage on metal grounded parts

What is the threat then?
Sorry for the stupid questions, but I'm green, and everyone was once
I am asking because it is important to me, because I play the guitar and the hum-ground amplifier solves this problem (I know, because it is enough for me to touch the strings or some other metal element where the ground is connected and the noise disappears, so then I do the ground). Just like the computer, I would not like it to break down in case of any failure
Do you know if it is possible to do grounding in one socket? How is it done? How much would an electrician / specialist take?

Added after 15 [minutes]:

I would like to add that the zeroing did not give much - the noise is still there.

"There will be a phase potential"

In fact, it may be incomprehensible, to put it simply, the metal housing will be connected to a 230V phase conductor.

What does it mean ?

More or less the same as a bare wire pulled out of the wall.

If you touch such a casing while standing on an insulated surface, you will feel a slight or stronger "kick" (muscle contraction). If, God forbid, you are barefoot on a conductive damp floor, you may end up with a serious electric shock with a disruption of the heart. However, if the other hand or leg touches a grounded metal part, e.g. a radiator faucet, it may result in a fatal shock.

This is especially dangerous for people with a pacemaker, even a small current flow through the body of such a person can disrupt the operation of the pacemaker.

Therefore, the TNC-S power supply system is currently used
For single-phase power, (ordinary mains socket with a pin)
phase conductor L (Line) black, sometimes brown or purple
neutral wire N (neutral) blue
and a yellow-green PE earthing conductor

In a three-phase socket there are 3 phase conductors, neutral and ground.

Double-insulated electrical appliances are recommended
(marked with a double square) do not require grounding.

In contrast, grounded devices that have metal parts
should be powered from a socket with a pin (which I described above)
and necessarily with the use of earth-fault protection.
(at least sockets in the kitchen and bathroom)

As for the shy questions, I think the forum is there to share knowledge, criticize, straighten ...

Shy questions add nothing to the discussion.
Like the statements:

I don't know much about it, but in my opinion ....

greetings

Moderated By kkas12:

Buddy, in this section, a layman will certainly not give advice to another layman.
I suggest that a colleague should stop at asking questions.
And I traditionally withdraw "help".

OK thanks.
But will it be possible to do grounding in one socket, as is a 2-wire installation?
How to do something like that then?

Unfortunately, with two wires, we only have the L and N wire.
The L conductor, which has a potential (voltage) of approx. 230V in relation to the N conductor, which N conductor should have a potential close to ground, i.e. 0V, as a neutral conductor. The N conductor goes through several connections and finally connects (at least it should be connected) to the building earth. This conductor N, if it is connected to the grounding pin, then acts as a ground, i.e. if for some reason there would be a breakdown in the device (insulation damage) such that the power supply from the L conductor would connect to the housing, then the current flowing from the housing to the connected pin with N, the protection should trip (burnout of the fuse link or trip of the S-type circuit breaker).

When we power a device that has a grounding pin from an ordinary socket (without a grounding pin), in the case described above (insulation damage and breakdown to the housing), a dangerous voltage will appear on the housing, and the effects are described in the previous post.

Unfortunately, when we connect the ground to the N wire, in the event of damage to this wire (poor contact in the terminal block, overheating and burning) we have a worse situation, because with a functional device, after turning it on, we have full voltage on the housing, the power goes from the L wire, then through e.g. the heater, it should flow to the N conductor, but because it is damaged, it only flows to the housing and possibly through someone who touches it.

In old installations, cross-sections were small, and new devices sometimes take more than 2kW (10A). Connecting two such devices, e.g. a kettle + cooker, is approx. 20A
it flows through the L and N conduit, if both of them are of the same cross-section then the probability that they will burn N is 1/2. The risk is high.

Therefore, if you decide to connect the ground to the N wire, you should check all connections of this wire, preferably if this wire "goes" directly from the main N strip in the apartment's switchboard and the N strip connected with a solid wire to the N strip of the installation. The protection of this circuit should be matched to the N and L conductor cross-sections. N must not be smaller than the L conductor cross-section.

You can see for yourself that the matter is so serious that it should be done by a licensed electrician who, having the appropriate instruments, will check the effectiveness of the protections, and measure the short-circuit loops.

To sum up, if you want to sleep peacefully and do not check with a neon lamp that there is no voltage on the housing, order an electrician, let an additional PE wire connect to the earthed sockets, he will know where to connect it and how to check the effectiveness of the protections. In this case, he should install an earth short-circuit protection for sockets in the kitchen and bathroom, which additionally protects against electric shock. You will be given a measurement protocol, and you will sleep soundly.

Moderated By kkas12:

A colleague does not distinguish between zeroing and grounding and thus also does not distinguish between network systems.
Please refrain from giving advice on topics about which my colleague has a vague idea.

stefan357213 wrote:

I asked my grandfather, he said it doesn't matter, but I prefer to be sure, because there are two ways.

You don't ask grandpa. He probably still remembers the times of Gomułka and protective earthing, and since then the rules of electric shock protection have changed several times. And the difference is what was discussed many times on the Forum - first we protect the zero to the protective pin and then with the zero wire to the zero terminal.
And in one room you either replace all sockets with a protective pin or none. This was also mentioned ad nauseam at the Forum.
If a two-wire cable is connected to an electrical outlet, it is an old system with protective zeroing.

stefan357213 wrote:

I am asking because it is important to me, because I play guitar and the amp hums

If the amplifier requires a protective conductor from the electrical installation, because it is a class I receiver, it should be like that. You connect the guitar to an amplifier.
To avoid noise, it is rather necessary to make equalizing connection between the amplifier and the guitar. Check the instructions for the amplifier on how it should be connected to the electrical system and how to connect a guitar to it.
If you have a problem with this, use the advice of a friend electrician, do not try to do it on your own, because it grows slowly and you can die quickly. Your health and your loved ones are the most important.

Hello,
will connect to the topic. At my home (with a two-wire installation), the bridging of the pins with zero is not made in sockets, but in boxes. That is, 3-core wires are connected to the sockets (brown for phase, blue for zero and yellow-green for a pin) and only in the box the blue and yellow-green wires are connected to a common terminal strip. Is this solution safe?

sheep80 , it is as secure as the above examples on the TN-C network. The separation in the PEN box into PE and N also gives you the purely hypothetical possibility of inserting an RCD.

And where would the RCD be mounted ???

What does it mean "in the forest"?
Maybe "in a can" ???

My friend kkas12 let's not pick on the details, please.

These aren't details.
These are the rules that must be followed.
This is Polish and the correctness of providing information.

This is not a place for a chat.
All advice fell.
I close the topic.