Hello. I have just moved in a new apartment and needs to replace a hob and install a new oven. We bought a 400v oven and a hob. Is it allowed to install a 400v oven in Geneva what I know the normal voltage here is 230v.

400V is 3 phase, 230 is single phase, so it won't work unless your oven has alternative single phase wiring!

(many do, read the user manual)

Tom

It is allowed, it just depends on how many phases your apartment has. As Tom stated, you need 3 phases for your oven, or alternatively a one phase wiring possibility which will be stated in the manual.

Can you see the junction box for your oven? You should be able to tell if there are 3phases or 1.

If there is not 430v in the building you are screwed ...

It is actually part of history here from the French side, had to sort out similar in my rented apartment. The owner did not realise there was no 430 v in the whole apartment block

Good luck with that, suggest you go and look at the distribution board in the first instance.

230 3P is 398V not 430V!

230*sqrt(3)

Tom

Dunno about you, but when I measure our mains voltage is comes to 239V; still not equating to 430, I know, but in any case it's all nominal and just as single-phase appliances are fine with voltages between 220 and 240, so should 3-phase stuff be OK with the equivalent range.

Unless it's really ancient, the odds are you have a 400V 3-phase supply in the kitchen. It may be possible to rewire the oven for 230V single phase, you'll need to look at the ratings plate at the back, but if you're not comfortable with such things, strongly recommend you have an electrician deal with it. As the oven will be operating at much lower power, it will take much longer to heat up.

It's not the oven that's the issue, it's the hotplates that could easily use over 7000 watts if all 4 rings were turned on hot at the same time. In reality it's not much of an issue unless you live in a very old flat with just 5 amps available, seen this in Basel multiple times.

230 +- 5% = 220-240.

400 +- 5% = 380-420.

117 +- 5% = 110-124.

Tom

Our oven has a "fast heat up" option which is (claimed to be) twice as fast if you have three phase, although it only uses two phases + neutral so probably it is treating it as two independent 230V phases to power different elements.

The hob requires three phases (and no neutral), so it's running everything at 400V which is easier on the current requirement. There's no option for two phase.

When using 18k lights for filming in Switzerland it was common to use a generator as relatively standard 64 Amp 3 phase sockets don't have enough power. I suggested using 2 phases & a step down transformer which worked perfectly. Using 2 phases is a perfectly valid solution.

400V IS using 2 phases!

It's 400V between any two.

Tom