What is wrong with the TN grounding hierarchy?

Question

Electronics

Hello, what is wrong with the TN earthing family hierarchy?

The TN system -> dead-earthed neutral and open conductive parts of electrical installations are connected to it by means of zero protective conductors. Everything is fine, at least 1 protective conductor, at least 10, and it doesn’t matter how these protective conductors are connected.

The TN-S system -> this type, in principle, should not exist, since it is the same as the TN-CS, only the place of separation of the ASU or the substation changes.

TN-C system -> theoretically, first PEN should be connected in series with the body of the electrical installation, and then used as a working zero, only in this way we get "zero protective and zero working conductors are combined in one conductor throughout its entire length."

But everyone considers the TN-C system, starting from the loop in the outlet, just a wire to the case that is separated, somewhere after the outlet or in the apartment panel or in the driveway, and even where the case is not connected to the neutral at all ... T. e. all this is actually the same TN-CS system. And where there is no connection between the case and the neutral, it cannot be called a grounding system at all, or in extreme cases, according to formal designations, like the "TI" system.

TN-CS system -> no questions, we make a separation of the PEN conductor, and connect it to the case in parallel.

Answer 1

With this question, it is better to contact the specialized forum on electrics.
By the way, you don’t have a specific wording of the question in the text - you give some of your descriptions of grounding systems (Although there are clear descriptions and pictures in the IEC or PUE, at worst, there are Beetle videos on this topic on YouTube), but the question as such you don't ask.
If you don’t want to listen to a forty-minute podcast with pictures, think about how different grounding systems will behave in case of possible combinations of accidents - because most of the differences in them relate specifically to emergency modes, including complex ones, such as “zero burnout on a transformer + TN-CS on the site = the whole farm is now draining zero personally through your earthing switch."