How to determine if kitchen and bathroom sockets are on the same phase in 3-phase home?

I have a simple and flimsy question, but a very interesting one.
In my house there is a 3-phase installation. And I wonder how you can check if the sockets in the kitchen and bathroom are the same phase or different ???

maybe it's trivial, but the first thing that comes to my mind is to disconnect one phase and check which sockets are not powered
and three times until we know everything about everyone.

I have already done so. I am interested in some way that does not require interference in the connection of phases

he can, for example, refer to the project. or check if the voltage from one point is in phase with the voltage from another point. but it is more cumbersome than lowering the fuse and checking that the light is on
greetings in the new year.

PS. there is still a hardcore way, but I do not recommend it to my biggest enemies. namely, if the two potentials are equal (the same phase) then theoretically you should not fuss if you catch yourself with them and lift your legs up. the only problem is proper coordination of movements. and that usually the first mistake will eliminate you from the evolution of the species.
to make it safer, you can use some volmeter. if there is no voltage between the "phases" (or it is small to a few volts) it is usually the same phase.

two 220V bulbs connected in series, one end of the phase in the bathroom, for example, and the other (via a long cable) to the phase in the kitchen. if it shines in other phases, if it doesn't shine it is the same. greetings

spros - your way is really hardcore and could certainly be used in the movie "Jacgaz - nuts in action" :)

ions15 - your way is also very interesting and I will try it, only it involves a huge amount of conductor. I will most likely use your way if nothing more interesting is found.

and it is impossible to solve it electronically ???

Just remember two bulbs in series.

why in series ??

dgaleza wrote:

and it is impossible to solve it electronically ???

Can be.
Instead of light bulbs, an electronic multimeter ;)

Added after 1 [minutes]:

dgaleza wrote:

why in series ??

and what if they don't get burned if they get 400 instead of 230

I understand.
and how is it with this multimeter ???

The method with a multimeter is to measure the effective voltage between the phase in the bathroom and kitchen.
If you take a measurement between the kitchen phase and, for example, zero of the bathroom, you will get 230V.
When you hit both phases during the measurement, depending on whether they are different or the same phases, you will get 0V or 400V (the meter will show the value resulting from the subtraction of the effective voltage vectors in individual phases - I recommend any electrical engineering book to learn the basics).
For example, if you hit the neutral wires of the bathroom and kitchen, you will also get 0V - as long as the installation is correct.
If you have never done such things, I advise you to skip this measurement and use ion-tichy's advice.
400V is no joke anymore, in the worst case it is a threat death .
Of course, you must have the appropriate multimeter.

greetings

I understand, but rather I will use the bulb method.

Added after 2 [minutes]:

PS. THIS THEME IS CONSIDERED CLOSED !!!