ᐅ Residual current circuit breakers with arc fault detection in prefabricated houses

Created on: 29 Sep 2017 18:58
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werners81
Hello dear forum,

We are currently building a new house with Keitel-Haus. In the additional cost invoice for the selections, we were informed that we need to install residual current circuit breakers with arc fault detection because our house will be built after December 18, 2017. After doing some research, I found out that this is due to a new VDE standard, which requires these devices to be installed, among other places, in wood-based constructions.

According to the insurance company, these are not necessary unless explicitly required by the local authorities. For the insurance, only what is specified in the regional building code regarding fire protection counts. The switches would cost almost 3,000€ for 11 circuits, which we would prefer to avoid...

Could you please clarify how necessary these are and whether they are really mandatory?

Best regards
T
Tanita
21 Feb 2018 07:16
We also resisted, as the construction company wanted almost €4,000.
The electrician told me during the installation that his company hardly ever installs these switches... that somehow says something to me as well...
Wissi21 Feb 2018 07:50
haydee schrieb:
The switches are not per RCD, but per circuit breaker/circuit [...]

From what I have learned now, both statements are correct! There are AFDDs available in four (roughly two main types with sub-variants) versions:

1/2: As an "add-on" solution attached to standard miniature circuit breakers and RCDs, where they control their respective neighbors via a mechanical shaft.

3/4: As combination switches. These can be used either with only MCBs or with a combined RCD/MCB.

Regarding Schwörerhaus, which we are building with: Approximately 27 AFDDs (arc fault detection devices) are actually installed. This number may vary slightly depending on the configuration, but it’s roughly accurate.
This disproves my assumption that only as many switches as RCDs are installed, at least in the case of Schwörerhaus. At least now I know what to expect and won’t think afterward that I paid for 27 but only received 7.
debaser21 Feb 2018 09:18
Funny that there happens to be a thread about this now. In our case, those things were simply installed without any specific calculations. They weren’t listed in the cost breakdown either.
I had to look up what these parts actually are first – I had never seen them before either.

But I won’t complain, especially when I see what some other home builders charge extra for them...
H
haydee
21 Feb 2018 09:32
Unfortunately, these prices from the home construction companies are not even outrageously high. The switches themselves are very expensive to purchase – until a few months ago, there was only one manufacturer. Installation and larger housings add to the cost.

It's great that they were installed so easily.
Wissi21 Feb 2018 09:39
debaser schrieb:
Funny that there happens to be a thread about this now. In our case, those things were simply installed [...]

Could you send me a picture of your distribution board?
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werners81
21 Feb 2018 09:59
In my case, the house manufacturer covered the additional costs after I was able to show that the standard is just a guideline and not a law. However, they couldn’t find an electrician who still installs without it.