Hello,
I've bought a few Swiss 3 pin plugs so that I can fit them to my UK appliances and not have to use a bulky adaptor. I came to do this today, then realised that the Swiss plugs don't have a fuse in them. Is this anything that I should be concerned about?
Are there any electricians or electrical engineers out there that can tell me why Swiss plugs don't have a fuse? Is the UK system over the top? Or is there better protection against surges etc at the fusebox in Switzerland? Or is there a fuse in the socket instead?
Cheers,
Chris
The main circuit breaker (on the circuit breaker board, probably in the cellar) would trip out, long before a fuse would blow, if there was ever a problem.
My house is divided electrically into a number of zones, each protected by its own circuit breaker, which trips at 10A. Except the one for the kitchen, which is a 16A fuse.
Fuses in UK plugs are typically 13A. Some are 3A some 5A. It's just a different system. I can't recall what the UK main board usually has - 30A, maybe?
Ah ok, so the main circuit breaker in the UK is rated a lot higher.
I wasn't particularly worried about protecting low value things like my toaster anyway, just surprised not to see a fuse having got used to always seeing it.
Is there any country other than the UK that DOES have fused plugs?
Tom
I was wondering that myself, and I can't think of any, other than the countries that use the British plug itself, of which there appear to be quite a
number
32A breaker (or 30A fuse) is used in the UK - for a ring main, which I don't think many other countries use - hence the requirement for fused plug-tops, as the fuse protects the appliance cable , not the appliance . If there's a fault in a 0.75mm2 appliance cable behind a 32A breaker then the cable would probably not be able to safely handle the prospective energy before the breaker trips - the result could be tiny blobs of molten copper flying around.
Here (CH), each circuit is radial, protected by 13A breakers (16A in DE, etc,) therefore no need for a fuse in the plug-top.
However.. in the UK, type B breakers are used (instant trip between 3 and 5 times rated current - i.e. max 160A) and here type C is used (between 5 and 10 times rated current - i.e. max 130A), so if you did have a fuse, I guess you would not get much discrimination (i.e. does the fuse blow first, or does the breaker trip first?) Might look at this actually, out of daft interest :-)
The reason why UK plugs have a fuse, relates to a shortage of copper after the war. By connecting the circuit at both ends 'ring main' thinner wire can be used & also less wire. It's possible to get 26 amps out of a UK double wall socket by using 2 x 13 amp plugs, it's quite safe to do. In other countries a 3 phase supply would be used when that much power is required.