Garage Wiring Issue: Current in All 3 Wires (L, N, PE) When Connected - Causes & Solutions?

Hello.
I'm doing my own installation in the garage and I have a rather unusual problem.
I lead the cable from the box from which I take the electricity to the socket and from it further to the box. Everything is fine, i.e. brown is L, blue is N, and yellow-green is PE. I check with a tester and it only lights up in brown. But then the stairs begin because when I connect the brown one in the box with the brown one that goes to the next point, I get current in all wires. The probe shines a little weaker but saints in blue and yellow-green.
I don't know what could be causing it and how to fix it.
I checked on other wires that come to the box and in others it is the same, so it's not the wire's fault.
I'm asking someone for help. I don't do it every day.

If the tester glows darker on the other wires, they are not connected anywhere, connect to the nipple and they will stop "shining". Read about inducing voltage in wires.

Mati79548 wrote:

I don't know what could be causing it and how to fix it.

It's very difficult, this liquidation, but maybe connect first all wires, then "test"

ciuqu wrote:

If the tester glows darker on the other wires, they are not connected anywhere, connect to the nipple and they will stop "shining". Read about inducing voltage in wires.

Only I want to connect the current to the light switch, so it only goes L in brown and in blue I want to make a return from the switch and give it to the bulb. And if there is current in blue when brown is connected, the switch will not work

Added after 3 [minutes]:

Krzysztof Kamienski wrote:

Mati79548 wrote:

I don't know what could be causing it and how to fix it.

It's very difficult, this liquidation, but maybe connect first all wires, then "test"

Look, not everyone is as knowledgeable about electricity as you are. If I knew where the reason is, I wouldn't be writing here. Your comment adds nothing. I have already connected all the wires to the switch, i.e. only L and the current appears in the other two

Added after 5 [minutes]:

Tumiwisizm wrote:

Hello, the wires are new or old from PRL stock. If it's old, it may be poor insulation, and if it's new, it's important that it's made of rubber. Also check before each point (box, socket) each wire or tester is lit (even dimly). If so, go to the previous point (box) and check if there is no breakdown from the phase wire to the other ones. Regarding what my colleague ciuqu wrote, in order for the voltage to be induced in a straight wire, located next to each other, the voltage must be much higher than that in the socket. Let me know I'm going.

The wires are new. 3x1.5 and 3x2.5
Well, it is so that in the wire that comes out of the socket there is current only in the brown one and when I connect only brown to the second 3-wire wire in the box, it appears in the other two

If the wire is not connected anywhere, a voltage will be induced in it, causing the tester to glow. If you have a meter, check if there is a short circuit between the wires, of course, after turning off the voltage. If you connect the bulb to the wires, the tester will not "shine" because the wire will be connected to N through the bulb.

Mati79548 wrote:

Well, it is so that in the wire that comes out of the socket there is current only in the brown one and when I connect only brown to the second 3-wire wire in the box, it appears in the other two

To begin with, no wires for lighting are led out of the socket box, according to the regulations, socket circuits should be separate from lighting circuits.
The voltage you measure with a neon lamp on the other wires of the switch is induced (that is, in layman's terms, a bit fictitious, you will not power anything from it and such a wire connected to N or PE will make the voltage from this wire disappear).

Mati79548 wrote:

Your comment adds nothing. I have already connected all the wires to the switch, i.e. only L and the current appears in the other two

It brings a lot. Connect all the wires and screw in the bulb and only then check with a tester. And green-yellow connect to PE. If you have only brown connected to L, and the other wires are not connected anywhere, the tester will shine on them (a little weaker) and this is normal.

Fellow author - no offense but - I suggest finding an electrician to perform this installation. From what you've said, it sounds like you don't "feel" this topic at all and you can hurt yourself.

I figured out what was wrong. I don't remember how because it was a long time ago.

Moderated By Topolski Mirosław:

Kol had everything explained in the hints. This example proves that if you want to do something, you must have basic knowledge of the subject.
The most important thing is that the team is alive and the right conclusions should be drawn from this example:
let the tailor sew, the doctor treats ..etc and the electrician performs the installations.