ᐅ 5-conductor cable to 3-conductor cable

I have a concrete garage from Zapf, where the electrical cables are embedded in conduit within the concrete. The embedded cables consist of 3 x 1.5 mm² (1.5 sq mm) wires. The supply line to the garage, which is routed through the floor, is made as NYY 5 x 1.5 mm² (1.5 sq mm). The five conductors have the colors yellow/green, blue, black, gray, and brown. Which three conductors from the 5-core cable should I connect to the three conductors in the garage? Yellow/green for grounding is clear to me, but which two other colors from the 5-core cable should I use? Good luck Raiweired

Definitely N blue on blue, and then you can choose a color in the 5x cable. These are the three phases, and you only need one.

Green/yellow is the protective earth conductor. If you are unsure about this topic, I would suggest consulting an electrician.

Thanks for the answers, it’s clear to me now 🙂

It is best to coordinate with the local electrician.

For the future, at least a 5x4 mm² (AWG 12) cable should be installed for a wall box, preferably 5x6 mm² (AWG 10).

In der Ruine schrieb:

Definitely use N blue on blue, and then for the 5x cable you can choose a color. Those are the three phases, and you only need one.

If you are giving advice to non-professionals, you should at least mention that the other two "spare" phases must be properly insulated. Simply cutting them off is not enough, nor is just wrapping them with tape. Otherwise, someone might eventually lie next to the cable in the garage and not get up again… especially since children like to play and grab everything.

So, amateurs should not mess with this but rather get someone who is qualified—and especially authorized—to do it.