Domestic wiring and plugs in Germany
I'm sure that you are aware that electrical plugs and sockets in Germany are not the same as those in the UK. You will know also that you can buy adaptors to allow you to use UK plugs in continental wall outlets.
There are also a few other things that you might like to know.
In the UK, a system known as a ring mains is used. A single cable runs all the way round part of a house interconnecting all of the wall outlets. This will be protected by one large fuse in the fuse box. A typical house will have three or four such rings. One for power downstairs, another for power upstairs and either one lighting ring per floor or one around the whole house. The power rings are normally proected by a 30 amp fuse and the lighting rings by 5 or 10 amp fuses.
Those fuses protect the wiring, not the appliances so, every appliance carries its own fuse in the plug.
The German system uses a star arrangement in which a cable from the fusebox feeds, for example all of the wall outlets in one room only. The fuses or more commonly, circuit breakers, are designed to protect not just the wiring but also the devices. So, there are no fuses in the plugs.
There is a slight voltage difference but this is not enough to be a worry. I have never heard of a problem arising from this.
The German mains frequency is the same as in the UK so that is another level of compatibility. Note, the US uses a different frequency and that does cause problems with some appliances even if a transformer is used to change voltages.
Today, the same plugs are used in most of continental Europe but some older systems had slight variations and you may find that some older plugs and sockets do not match up.
One other thing to remember is that these plugs and sockets can all be plugged in either way around. So, if you have a UK appliance plugged in with an adaptor then even if you turn the appliance off with its own switch or if the fuse in the plug blows, you may still have a live voltage in the appliance depending on which way up you inserted the plug!
In the UK, you will normally only ever see a single phase supply in a house. This not the case in Germany. Separate rooms in the same apartment may be on diferent phases and, even more of a surprise, you may well find that you have a three phase supply for your cooker. Because of this electric cookers are not interchangable between Germany and the UK. But more important than this is the fact that three phase packs a much bigger punch than single phase An accidental shock from single phase mains is unlikely to kill a healthy adult. (I should know, I've had several.) However, a whack from across two phases of a three phase supply will kill most folks so be warned.
If you do not know what three phase is then just walk away and let a professional sort out your wiring issues in Germany.
I say again, unless you are a pro, stay clear of the wiring inside your fuse, or breaker, box and stay clear of the wiring to your cooker. It can kill you just as easily as I can open another bottle of Chateau Grand Puy Lacoste.