ᐅ Electrical Planning: What to Consider? Process, Explanations, and Tips

A very useful website on electrical topics has been created through the collaboration of several manufacturers and trade associations.
Free informational material can be downloaded there or requested in glossy print.
It is not a commercial site.

Initiative Elektro+

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Hello,

I appreciate the effort you put into electrical planning; users will certainly benefit greatly from it. However, linking to external sites is not equally welcome, so I have removed your link (forum rules). A reference to the name and a quick search on Google will also lead you to the right place.

Regards, Bauexperte
Bauexperte

Wow, thank you very much for your effort!

Well done, those are really good tips for beginners!

Thanks for the helpful tips!

The RCD
The RCD is a residual current device designed for personal protection.
The standard specification is to install a 40A, 30mA version.
40A is the maximum current that can flow through the RCD, and 30mA is the maximum residual current fault at which it must trip.
An RCD with a rating greater than 30mA is not permitted.

Nonsense,
RCD protection devices with ratings above 30mA are also approved.
According to VDE 0100-410, the 30mA RCD is only required for sockets up to 20A indoors and up to 32A outdoors (I will skip further details).
Lighting circuits and appliances such as electric stoves do not have to be connected to an RCD, especially not a 30mA one.

That it is still better to install one, I do not deny.
But no one should be encouraged to upset the local electrician.

One RCD for the entire house is not enough, don’t let your electrician tell you otherwise.
A sensible division would be, for example:

1 RCD for sockets
1 RCD for lighting

Here again, the mistake lies in the details.
Standards require that a total outage must be avoided in case of a fault.
If there is only one RCD for the lighting, well then you have a total blackout you want to avoid.

You can do without RCD protection for sockets, but certainly not for lighting.

Therefore, either
split lighting and sockets across at least 2 RCDs, or install 2 RCDs for lighting so that every second room is connected to the second RCD.
This way, you can at least find your way to the distribution board if the RCD trips during, for example, lamp installation.

So I use 16A circuit breakers for the sockets and 6A or 10A circuit breakers for indoor lighting.
The reason for this differentiation is the tripping time already mentioned.

If lighting circuits are supplied and protected with a separate feeder, only circuit breakers with a maximum rating of 10A are allowed.
Why?
Because the breakers are usually only approved up to 10A, though there are exceptions going up to 16A. You can usually recognize these by the price.
If sockets and lighting are supplied on the same feeder, 16A circuit breakers may be installed, since in practice it is unlikely that the total wattage of lamps in a room exceeds 2300W.
And if you want more power in the living room, you simply install 16A breakers.

Large appliances such as washing machines, dryers, refrigerators, dishwashers, ovens, cooktops, fully automatic coffee machines, etc. each get their own fuse.
Especially appliances with more than 2kW power. For powers of 3kW (tankless water heaters), a 16A circuit breaker is no longer sufficient, and the feeder cable must also be sized larger.

The DIN standard recommends a separate feeder for appliances above 2kW, which also covers the 3kW tankless water heater. This means, for example, that the kitchen should have around 4-5 feeders planned.

As you can see, quite a lot adds up, so you should plan your main distribution board accordingly.

The main distribution board is planned by the electrician who submits the application; you probably mean the main distribution panel / meter cabinet.

Sockets:

You can never have enough!
I have a personal dislike of multi-plug adapters (sometimes you can’t avoid them).

Power strips must not and cannot replace a deficient installation; this is also specified in the standards.

Sockets outside on the house wall should be switchable from inside and must also have a cover.

Here, a double-pole switch with an indicator light should also be installed. That way, no one can trip the RCD while you are on vacation — you just need to turn off the switch.

Network, Telephone, and TV

Plan network outlets wherever TV, PC/MAC, laptop, router, etc. will be located.
A telephone point is usually sufficient in the utility room nowadays, but additional points in hallways and bedrooms can still be useful.

It is important that all cables for telephone, network, TV/SAT, etc. are installed inside empty conduits.
1) Because it is a regulation
2) Because this allows for cable replacement if needed

All cables should be run in a star topology.

Homebuilders are often overcharged for this because it is a significant cost item in the quotation.
Also, make sure each network port has its own separate cable to fully utilize the bandwidth.

It is advisable to install 3-4 empty conduits to the attic. Even if you plan only a cable connection, install at least two conduits for the SAT system and one 16mm² (5 AWG) cable to the attic for grounding the SAT system (be sure to pay attention to the routing here).
Later, when the children are older, the attic can potentially be converted and supplied with power without having to dismantle the entire house.

The Foundation Earthing

The foundation earthing is a crucial component for all fault currents that may occur. If it is not installed correctly, the protective function of the RCD (residual current device) is compromised.

However, here I must raise a veto.
If this were true, there would be no RCDs in buildings without foundation earthing.

A main equipotential bonding bar to which all conductive parts must be connected, e.g.:

Incoming cable connection, network cabinet, antenna system, and more.

I believe I read somewhere in a DIN standard that this is allowed as long as both ends are covered with colored heat shrink tubing.

It is, was, and will never be allowed. See the VDE standards.

Wall Chasing

Vertical chasing in walls is allowed.
Horizontal chasing is not allowed because it endangers the structural integrity.
Therefore, always route cables from socket to socket either along the floor or in the attic.
If the electrician wants to use flat cables (stegleitungen), forbid it. They are allowed but become extremely brittle over the years and thus a potential source of faults.

Where and how chasing is permitted is determined by the structural engineer; various guidance can also be found online. The wall thickness is one of the deciding factors.

As long as flat cables remain untouched, they generally do not cause issues. In about 25 years, I have not seen any complaints not caused by external factors, similar to NYM cables.
However, NYM cables are the better choice, I agree.

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Additions like garages should be connected to the house via a duct, at least if not built directly near the main distribution panel. Alternatively, telephone, network, and at least one line for three-phase power with a minimum capacity of 32A should be installed.

Wood splitters, hobby workshops, party rooms, etc., may become relevant for you in the future.

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If building over two floors, a separate distribution panel should be planned on the upper floor. This saves cabling and saves trips downstairs for circuit breakers. It also keeps the size of the distribution panel on the ground floor manageable.

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@ Elektro1

Thumbs up from me for your contribution; it offers a good starting point and helpful advice.

I hope you will forgive my objections.

Best regards