The ceiling connection is the moment most people are wary of. Rightly so, because 230 volts flow here. But it's also the most standardised step of all: three cores come out of the ceiling, three cores go into the light, and the colours tell you what goes where. If you're not sure after reading this, have an electrician do it – that costs 40 to 80 euros and is money well spent. What's written here doesn't replace training; it explains what happens.
First: power off and test
At the fuse box, switch off the room's circuit (circuit breaker down), and the RCD as well if you're not sure which circuit it is. Then check at the ceiling outlet with a two-pole voltage tester (not a screwdriver-type phase tester, they're unreliable) that there's no voltage between any pair of cores. Only then carry on. A note on the fuse box stops anyone from “just quickly” switching the light back on in the meantime.
The wires from the ceiling
Standard colours in modern installations: brown or black = L (line, the "live"), blue = N (neutral), green-yellow = PE (protective earth). In older buildings you may also find grey or red as L and black as N – in those cases, don't carry on without a meter. If five wires come out of the ceiling, the light is wired to two switches or a two-circuit switch: there are two switched L wires, and you decide whether both go to one light (then it switches from both switches) or only one.
The ceiling rose
A good ceiling rose has three parts: a ceiling plate (screwed to the ceiling or hung over the existing fixing), a connector (terminal block or push-in connector, at least 3-pole) and the cover that hides it all. Plus the strain relief the fabric cable runs through: it carries the weight of the light so it doesn't pull on the terminals. Without a tightened strain relief, the cable can work loose over the months – the most common cause of loose contacts in self-built lights.
Wiring
Fit the ceiling plate. Push the light's fabric cable through the cover and then through the strain relief, leaving about 15 cm sticking out. Remove 8 cm of sheath and strip 8 mm from each wire (10 to 11 mm for push-in terminals – it's marked on the terminal). Then connect: L from the ceiling to L of the light, N to N, PE to PE. With a 2-core fabric cable (2x0.75) there's no PE on the light side; the earth wire from the ceiling then goes into a spare terminal and stays insulated – never just cut it off or leave it exposed. With metal ceiling roses and metal lamp holders, you need a 3-core cable and connect the PE through.
Tighten the strain relief, give the cable a short tug: it must not move. Slide the cover up and secure it.
Switching on
Screw in the bulb, switch the circuit breaker back on, flick the light switch. If it lights up, all is well. If the breaker or the RCD trips, usually a strand is sticking out sideways from the terminal (short circuit) or N and PE have been swapped – power off, open it up, check.
What the electrician does differently
Not much, but more thoroughly: they check the pull-out strength of every terminal, make sure no single strand of a fine-stranded cable is sticking out next to the terminal (fabric cables are fine-stranded – ferrules are the clean solution, and a ferrule crimper costs 15 euros), and test the earth conductor for continuity after installation. That pays off with lights that have a lot of metal and with old wiring.
If you'd rather just connect the ceiling cable: every design in the configurator can be ordered “pre-assembled” – the light then arrives wired and tested, and all that's left at the ceiling is the step from the “Wiring” section.