How to connect a spotlight to a power outlet..?

Are the spots connected with 220V or via a transformer. If the cables are only thin and two-core, stay away from them, you'll burn the house down

Are the spotlights connected with 220V or via a transformer? If the cables are only thin and two-core, keep your hands off, you'll burn the house down

Nothing is burning down at all. There are circuit breakers and RCDs before anything burns. If he applies 24V DC to the socket, at most the connected devices will break (not necessarily either). But that is precisely why the advice was already given to have a professional do it.

nothing burns at all. There are circuit breakers and RCDs before anything can catch fire

Don't rely on that, it can still catch fire. Too much current heats up cables. The dielectric melts away, it starts to burn. Only a short circuit triggers the breaker, heat does not. You can try it in the garden. Put a load on a coiled cable drum in straw. It burns before a fuse trips – or shortly after.

Put load on a coiled cable drum in straw. It burns before a fuse trips.

But it was not about a coiled cable drum, it was about a socket with 24V direct current. That was probably the danger being pointed out. Above my drywall, there is non-combustible mineral wool and no straw, and also no 50m tightly coiled cable with 3KW load.

Even if I had 50m of coiled cable up there and a 3KW load... I would bet everything that the RCD trips first before my mineral wool or the roof beam burns. And even if it did. That would then be a theoretical construct in an LED spot installation.

But here it's about LED spots with maybe a total of 100W, without straw and without tightly coiled cables.

Only a short circuit trips,

the RCD also trips on residual current.

You have probably already understood this: do not rely on fuses when working with electricity. Fires can also occur due to improper installation despite proper fusing. I consider it unhelpful to lull an obvious layperson into a false sense of security. There are many other mistakes one can imagine; laypeople are creative in that regard. Placing the cable drum on straw is just one variant among many.

I consider it unhelpful to give an obvious layperson a false sense of security.

therefore, I (not only) have already referred to a professional ;) I think we have understood each other and basically agree. In this case, there is a lack of basics -> get a professional. With my post about nothing catching fire, I explicitly addressed the above-mentioned case of hanging a socket on the two thin +/- wires. Nothing more and nothing less. That there are 10,000 ways to cause a fire through electricity and that fuses are a panacea, I have not said and would not say. But I admit that one could interpret more into it than is there and then come to this wrong conclusion. We have now clearly established that again :)