Outlet Voltage Fluctuation: Flickering Lights, 170V-230V Range, Heated/Unscrewing Plugs

Hello and welcome.
I hope it's the right section.
My problem started when the light bulbs in my room started flickering. I had to turn on the light in the kitchen to stop them blinking. In some sockets, my microwave oven, printer do not work .... I measured 210V in one, 170V in the other. 228-230 in others.
I am the first from the transformer, one plug in the board is heating up, also 2 plugs unscrew themselves.

What could be the cause? Thanks for your answers.

Is there an overvoltage on that fuse? Maybe the socket is burned out, or the wires to the socket? Regards

Fircyk81 wrote:

What could be the reason

It's like fortune-telling. Not enough details.
Probably an old aluminum installation with fuses.
There can be many reasons: poor contact of the cable in sockets, junction boxes, switchgear. Loose neutral contact, etc.
Solution:
Inspect the installation, from the socket through the junction boxes to the switchgear, and check the condition of the connections.

surges? Does it mean it burns? Once in a while yes, but rarely. Just tighten. I'll check the socket tomorrow. But would it affect 170 volts in the socket?

jack2com wrote:

Solution:
Inspect the installation, from the socket through the junction boxes to the switchgear, and check the condition of the connections.

a job for an electrician. The installation is 20 years old.

First of all, we have fuses in the installation, not plugs as in the bathtub. Well, now to the point. Is it a 3 phase installation? because if so, it may be that one of the phases is too heavily loaded and there are voltage drops. Also check if the fault is not on the ZE side, i.e. invite an electrician to check the voltage values right behind the meter. It may also be that the transformer is overloaded too much, but that's more of a ZE problem. Voltage deviations may be a maximum of 10% of the rated voltage. If it is less, you have the right to advertise poor quality energy. So you can see for yourself that there can be many reasons. It's best if you invite an electrician and he will measure and check everything on site.

Fircyk81 wrote:

a job for an electrician. The installation is 20 years old.

Well, here you need an older, good electrician who gained experience on such installations.
The fuse and the fuse socket in the switchgear are probably quite warm, the foot of the socket under the fuse may be burnt out.
In fact, it is necessary to perform a technical inspection of the receiving installation by an electrician. And as soon as possible, because most fires are caused by the poor condition of the electrical system.

Of course it can have an impact.
As a colleague wrote above - the entire installation from the fuse board to the sockets themselves - for review.
Loose neutral, lack of contact on the fuse socket, burnt wires (especially if they are aluminum), possibly loose wires in the socket-socket lead.
For now, these are just guesses.
Check each point of the installation well and write what disturbing you noticed.

Bronek22 wrote:

There is no zero and asymmetry.

This is not the way how the complete lack of zero can be. It would be immediately noticeable. You probably wanted to write that a poor contact on the neutral wire, or PEN if you prefer.

Yes, 3 phase installation. I'll try to look myself.

You, my friend, do not look, but look for a good electrician, because such a condition is a serious threat.

Measuring the short-circuit loop impedance will help solve the problem, but that's an electrician's job.

Earlier, I wrote to a colleague: "You have not written what you have already checked, and you can make a rational decision only when you have a sufficient amount of information." Unfortunately, you didn't draw any conclusions. At the moment, colleagues have provided enough information to diagnose the fault, so I close the topic.
This is how it is when you forget about the early art of detecting damage - inspections / inspection, or maybe tinkering yourself without sufficient professional training ...