TN-C Network: Cable Thickness & Differential Power for Meter to Switchboard Setup

Welcome back
I have a question, what thickness of the cable to lay from the meter to the switchgear in the apartment?

At this point, I have an old two-wire installation. from the meter to the fuse at the meter, I have thin wires, max 4mm2 (although I do not know if it is 2.5mm2), further to the apartment for the entire 2.5mm2 installation. I want to divide the PEN conductor into PE and N and here the question is whether to lead 2x4mm2 from the meter to the switchgear and divide it on the PE strip in the distribution board in the apartment and then to the differential N. Do the division already at the meter and from the 3x4mm2 meter? I saw that there is a free PE strip screwed to the housing.

Another question is what power of the differential to use in the switchgear, since the main fuse at the meter is b20, I will install b10 and b16 behind the differential

The type of network in my tenement house is TN-C, my allotment is 1-phase installation

PriweR wrote:

I want to divide the PEN conductor into PE and N and here is also the question whether to lead 2x4mm2 from the meter to the switchgear

Do you want to run a new installation with a 2x4 section ...? Are you kidding me?
What is the minimum cross-section of a PEN vein?

I know that the minimum cross-section is 10mm2. I had rolled it over before. But if I have a thin 2.5-4mm2 cable led to the meter, then I should put a thicker cable behind the meter?

You are to perform the new installation in accordance with the current regulations.
Even if your pre-meter part is made of string or barbed wire.

Will I not have a power loss because of this? So I understand that I should put 10mm2 from the meter to the switchboard, yes?

Where to split the PEN? at the meter or in the switchboard?

PriweR wrote:

I want to divide the PEN conductor into PE and N and here the question is whether to lead 2x4mm2 from the meter to the switchgear and divide it on the PE strip in the distribution board in the apartment and then to the N differential.

The tenement house is a friend's property or only its tenant. Because if the latter is the consent of the owner.

PriweR wrote:

Do the division already at the meter and from the 3x4mm2 meter

Only 3x 10mm2. The breakdown will be made by an electrician after inspecting the entire installation.

Why 3 x 10mm?, buddy Krzysztof Reszka ?

PriweR wrote:

So I understand that I should put 10mm2 from the meter to the switchboard, yes?

I propose to rethink the 3-phase power supply for the apartment. Even if you use 3x16, you will still be limited.
In practice, 3x6mm2 or 5x6mm2 are used.

He can give up five times if he predicts the disc in the future.

If there is no idea for the modernization of the rest of the installation to a cable joint / or TG, I suggest only 5x10.
I am currently doing a project in a block of flats and I design 5x10 for each apartment (after discussions with the cooperative). Surplus today, but salvation for the flat / residents in a few months.

Krzysztof Reszka wrote:

The tenement house is a friend's property or only its tenant. Because if the latter is the consent of the owner.

The tenement house is completely bought by the residents. The apartment is my property and part of the community


As for the division and interference in the installation behind the meter, after contacting the power plant, I received information that you can do everything on your own without having the appropriate permissions. But to dispel this, I have a person with permissions who will sign this installation for me, make measurements, but I will motivate it myself. This person, M.Sc., an electrician, told me to distribute PEN in the apartment in the switchgear, but let's not discuss this topic anymore.

I wanted to get hints on the forum because you can find out interesting information and dispel doubts here.

jann111 wrote:

I propose to rethink the 3-phase power supply for the apartment

it probably won't be necessary? I have a small apartment

Coming back to my questions, where to make this division according to you?
What 1-phase differential should be used, if the protection at the meter is b20?
and do you really pack such thick cables?

or maybe if a colleague suggests 6mm2 is enough


Earlier, I asked for 4mm2 because I have a lot of new cable, my brother's company put the power supply to summer cottages from the main one to the switchgear with just such a cable.

and in this thread we are also talking about such a cable https://www.elektroda.pl/rtvforum/topic729920.html

opornik17 wrote:

If there is no idea for the modernization of the rest of the installation to a cable joint / or TG, I suggest only 5x10.
I am currently doing a project in a block of flats and I design 5x10 for each apartment (after discussions with the cooperative). Surplus today, but salvation for the apartment / residents in a few months.

and does such a large cross-section carry some power losses if the power supply is on a cable with a smaller cross-section?

PriweR wrote:

Earlier, I asked for 4mm2 because I have a lot of new cable, my brother's company put the power supply to summer cottages from the main one to the switchgear with just such a cable.

zbich70 wrote:

Even if your pre-meter part is made of string or barbed wire.

Forgive me, but the experts will not confirm your ideas. You got a buddy on a tray of information from us. What do you do? Your business.
I do not need to sign anywhere.

Okay, I will do it according to the standards in force and if I increase the allocation for 3 phases, I will put 5x10mm.

I would just like to know what the effects will be if a thinner cable is placed in front of 10mm2?

I would also ask for a hint about the RCD and what to do with the PEN division.

But why 5 x if the cross-section is supposed to be 10 mm??
Maybe a friend resistor 7 explain?

elpapiotr wrote:

But why 5 x if the cross-section is supposed to be 10 mm??

So far, this is PEN and whether it will always be it will not necessarily be an obvious matter.

elpapiotr wrote:

But why 5 x if the cross-section is supposed to be 10 mm??
Maybe a friend resistor 7 explain?

Please
5x because I assume a power increase and a 3-phase meter in the apartment.
10 because today there is zeroing in the apartments, the power supply network in TN-C and the residents do not declare the reconstruction of the installation.

And I do not set up a meter in the apartment.
The rest of the translation ... confusing.

PS. If there will be 4x10 mm?, it is not possible to set up a 3-phase counter?

You can always assume that the meter has nothing to do with the number of veins. The topic raised here many times is a multi-family house (such a block)

PriweR wrote:

The tenement house is completely bought by the residents. The apartment is my property and part of the community

So the WLZ installation should be adapted to the current requirements. Then the discussion as to the number of veins and the diameter will be pointless.

elpapiotr wrote:

PS. If there will be 4x10 mm?, it is not possible to set up a 3-phase counter?

What will you do after you switch to TN-S in the block? A set of TG / TA with administrative zones located in the basement and there is a division of the PEN. Measuring sets for apartments also in the basement.
PS
I know we write from different points of view. It is difficult for me to paste a technical description and drawings from the project here.

In the future, as a community, we will probably plan to replace the installations in the entire tenement house, but I would like to know what the consequences will be at the moment if there is a 10mm2 cable on the way from the meter to the apartment and the cable with a smaller cross-section will be used with it?
At the moment, I want to set up the installation on the ring correctly so that I do not have to hammer the walls in some time, I will also put 5x10 and unused protection cables at the meter and in the switchboard.

Will you suggest what about this PEN division and where to do it? do I have to create a new topic?

The PEN division is to be made on the multi-story rosette. During the modernization of the installation in the tenement house, the electricians will know what to do next.
And don't worry about the cross-section for the meter. They will use the same as on the drain.

There is one more option. Namely, if the conditions allow it (the section must be relatively straight), you can carve a larger furrow and brick a decent conduit, taking care not to break it anywhere or damage it mechanically during plastering. At the moment, single LgY wires can be pulled into the conduit, eg PEN 10mm2 + "phase" 4mm2 (budget option). In the event of switching to a 3-phase or TN-S installation or increasing the power allocation, it will be possible to pull out the old cables (they will serve as a pilot) and pull in new ones, appropriately selected for the type of installation and power. I just don't know if it is technically possible in this case.

Adam_Bandit wrote:

Namely, if the conditions allow it (the section must be relatively straight), you can carve a larger furrow and brick a decent conduit, taking care not to break it anywhere or damage it mechanically during plastering. At the moment, single LgY wires can be pulled into the conduit, eg PEN 10mm2 + "phase" 4mm2 (budget option).

What cash register can we discuss here? Let's not get paranoid.

PriweR wrote:

Will I not have a power loss because of this?

By using a thicker wire made of the same material, you will reduce losses.

I am not an outstanding specialist, but in my opinion 5x6mm ^ 2 and the PEN division in a two-story box will be the optimal choice. The final decision will be made by the one who signs it. Find out what you are allowed in the building so that you won't have any problems later.

6mm ^ 2 and this is supposed to be PEN? Oh

pol102 wrote:

6mm ^ 2 and this is supposed to be PEN? Oh

A colleague above wrote that 6mm? after the chapter.

For the author, 3x6mm? would be enough, but in today's realities, it is worth putting 5x6mm? immediately, the cost is small during renovation. In the future, if, for example, an induction hob appears, it will not be a problem. On this occasion, immediately pull 5x2.5mm? to the kitchen, and provide a reserve in the home switchboard. At least 12 extra modules.

In my opinion, giving the 5x10mm? line to an apartment in a tenement house with central heating is a slight exaggeration.

I do not know.
In the past, people thought similarly, and as a result, we find today h2s with a cross-section of 2.5mm2.
Personally, I do not see any error in oversizing this installation element.
Of course, in a multi-family building with meters on the ground floor, this is reflected in the costs.

Of course you can, you just need to use common sense in the end. If someone is rich, he will add 5x16mm2 to the apartment in advance.
With 3x25A protection from the staircase to the apartment in the dark, 5x6mm2 is enough without counting.
We are not talking about a detached house, but about a small apartment in a tenement house, where heating comes from a local boiler room or from the city.

Let's wait a few more years, who knows whether the honorable EU will not start to reduce the connection capacity

Rather, I think these limitations will disappear.
I cannot imagine that a British or Irishman would suddenly replace the current 80A protection (in front of the meter) with 25A.
Well, let's say 40A because it's one phase.
Or he was rebuilding the power line to a three-phase one.

And it seems to me that this change in our country is only a matter of time.