Double Phase in Socket: Apartment Wiring, Distribution Box, Washing Machine Power Issues

Hello,

I have a problem, and because I am not a professional electrician, but a DIY enthusiast - I do not know if I can handle the problem myself.

Situation:

An apartment in the Gierek block. Installation is quite strange for me: a two-wire cable goes from the fuse to such a distribution box with two rails. From these rails there are parallel (!) Connections to individual rooms. Maybe it's normal, I'm used to serial circuits at least when it comes to sockets. Let me remind you: I am not a professional electrician.

Problem:

The "washing machine" socket in the bathroom fell out of the wall (it had been torn out), but the wires were plugged in as is. The washing machine was working, it happened recently so I was just getting down to "putting" the socket in its place. I know that the plugs were burst later (from the reports of the household members), but after turning them on, the washing machine continued to work. Then she stopped altogether.

I checked - in one "hole" of the socket there is a phase, and in the other ... too! Same on the reset pin.

I set it all up. There are three wires in the outlet: two blue and one black. In black and the first blue there is a phase, in the second blue there is nothing (neither phase nor zero). Both blue ones were originally bridged.

What happened? How could the phase appear in the neutral wire?

Unfortunately, I do not know exactly how the installation was built, because I bought a flat "done", and in this place the electrics were changed - the wires are under the tiles.

Does anybody have an idea? Before I get an electrician ...?

Martini

do you have access to a meter or indicator that you can check the voltages between individual wires?

I have access to the meter, I will measure it today.
But maybe someone will give me some advice based on what I know?

I just read on ISE.pl that this switchgear (central distribution box) is a typical solution from the 70s and that there are so-called scorched zero. Could it be THIS judging by the symptoms? But where does the phase in two wires come from?

Probably the "neutral" wire is broken or not connected and therefore the neon indicator shows phase. Use a light bulb to check the phase and neutral wires.

I checked everything. The neutral wire shows 50V in relation to the washbasin, the bathtub and the neutral one pulled from another socket with a longer wire.

Where the hell did 50V on the neutral?

Evidently, the zero has broken, first you should check the nearest wire connections (box), although with a complete plugging of the installation it can be a problem. Calling a kumaty electrician can be a solution, often it is possible to locate the damage with an accuracy of a few cm, it is enough to move your head a little

Okay. I will try to choose the box - it is behind the buildings in the hall, there will be some work with it, but I can do it.

And can someone else explain it to me - if the zero "has broken", where does the voltage ~ 50V come from?

1-because a neon tube - or a digital one was used - in this case you need to use a 230V test tube.
2nd false phase passes through the wire insulation - it gives the phase.
Hence the need to test under a load, e.g. light bulb.
3-such "burned" zero / wire / aluminum can be in the socket - but it can also be in this distribution point.
All disconnections of worn-out aluminum wires must be carefully performed - because they can PĘC also in insulation.
4-basically no need to feel sorry for it-better to replace with good copper wires right away-later searching under the tiles is very difficult.
5-I used to drill from the bathroom -through tiles, in the direction of the distribution box -bo "zero" and the rest of the alu. she was battered / thermally overloaded /.
6-you can also -to this test tube give "zero" from another good socket and
in this way -in the damaged one to find this correct phase -light-
and mark this broken zero wire - it does not glow.

I had the same case. The fault turned out to be the failure of the UPS, which also had a phase at the N output. After disconnecting the UPS, everything was OK.
In the TN-CS network, if we talk about such a potential, the potential moves through the N conductor. Maybe the neighbor has a damaged device?


I am interested in what happened in this case. Could you give a reason?

I can see a slight discrepancy here. The author writes about a socket in the bathroom with a pin and claims that the two blue wires were bridged - hmm ..
I assume that he did not connect them to PE because otherwise he would not write about 50V in N.
However, we still have info about the voltage on the PE pin.

MartinusMaximus wrote:

Problem:
I checked - in one "hole" of the socket there is a phase, and in the other ... too! Same on the reset pin.

I had a similar case once - it turned out that the fuse was placed on the N wire instead of the phase one! greetings

Pavciu wrote:

I can see a slight discrepancy here. The author writes about a socket in the bathroom with a pin and claims that the two blue wires were bridged - hmm ..
I assume that he did not connect them to PE because otherwise he would not write about 50V in N.
However, we still have info about the voltage on the PE pin.

Hi,

I'm already clearing up the matter:

there are actually two wires there - phase and zero.
This is an installation Two-stranded .
The third one is actually a "derivation" of zero to illuminate the mirror, someone's DIY.
The zero pin is thus bridged with the zero wire.

Briefly, this reset is AC ~ 50V. I do not know where from, but I will simply bring the 'zero' from the box independently and insulate this low-profile wire. Is that enough, or do I have to look for where it is coming from and cut it?


I would like to add (to other statements) that I do not have a UPS, the fuses are on L.
Probable cause in my opinion: the old cable burned out by starting the socket.

If anyone else has any idea - please write. This is an important matter for me, it is about safety after all.

Something else dawned on me - do not connect this cable from the mirror lighting or unscrew the bulb and check what is happening.

If your N wire is burned out, if you plug in a lamp about 60W, it should not light - check.

If you have no experience, ask an electrician for help.
Remember to work with disconnecting or "moving" the cables without voltage - remove / switch off the fuse and check that there is no voltage.

Next:

Start with a visual inspection. Check if the wires are not cut - it often happens when someone unskillfully pulls the insulation. Check that the wires are properly tightened. Check the condition of the insulation in the fuse box - it happens that the wires overheat and when the insulation grows old, it breaks down (like L with N touches / crosses).



If the visual inspection shows nothing, do the following test at the beginning:


1. See what sockets are powered by the fuse you write about and check the voltage in another socket on the same circuit.

2. Disconnect all receivers from sockets (if it is an installation where separate circuits are for the sockets and check the voltage in this socket.

3. Turn off the voltage by unscrewing or turning off the fuse (depending on what type you have), measure the voltage and give the results. If there is no voltage on N, then I would exclude a breakdown from L and I would suspect another damaged device connected to this circuit (e.g. damage from L to N or PE if someone split this wire) and thus you can have 50V at home.

Enter the results so that the cause can be estimated.

In installations with CPR, the installation was pulled from socket to socket and returned to CPR. Probably someone who changed your installation did not take this into account. I advise you to check which socket is powered from the circuit in which you have no voltage. the phaser does not give clear answers and you will not check zero.
Installations with CPR were also used in the 1980s in WK70 panel construction (not only in the 1970s)

and is everything ok in the other sockets?

Hi,

the case has (I think) cleared up.

This is a Leningrad-type block, not WK70, but CPR is.

This socket - as an exception - is connected directly to the CPR - so everything is fine in other sockets.

After breaking part of the wall unit and hitting the box, it turned out that the connection in the box had burned out - the old insulation had melted - maybe as a result of overvoltage? I don't know, but there was a smell, and the insulation looks like after a visit to a fire. I cut off the damaged elements, insulated it and left it for now (for Christmas). After this operation, there is no mass, zero or the 50 V in the socket. I checked everything with a meter.
I think that when I connect it with a fresh cable - everything will start to move.

Thanks for your help and happy world!

Martini