On 16/01/2012, George Brock-Nannestad wrote:
> In the UK, things are very interesting indeed. They do not have main
> circuit breaker fuses but fused outlets, or rather fuses in the plugs.
Actually we have both. There is a fuse in the plug, which is supposed to
be of appropriate value for the equipment, AND there is a circuit
breaker for each ring main.
The lighting circuits are separate from the power circuits and the
circuit breakers are for lower amps.
Before circuit breakers appeared, there was a board full of wire fuses,
and a bit of card with fuse wire wrapped round it for replacement.
> And very many use ring mains, i.e. the circuit through the house has
> two parallel circuits going round and back to the main switch. This
> very much reduces the voltage drop on the in-house distribution. This
> is in sharp contrast to the star system used in Denmark, but I suppose
> you need it because the "normal" plug for kettles and the like has a
> built-in 13 A fuse, and you can have both your kettle and a toaster on
> at the same time. Not so in Denmark, you are limited to 10 A. A normal
> fuse has a time function that makes it blow instantly at 1.5 times the
> rating, and I suppose in one hour at 1.1 times the rating - I haven't
> checked since 1970.
We are allowed to have spurs branching off from the ring, too.
The regulations are strict and detailed.
> All the things you did not want to know about mains! And we have not
> even started on 3-phase.
> But Tom's photographs are beautiful!
> Best wishes,
>> Hi, Tom,
>> Wow, what memories this brings back. The only equipment that I have
>> ever owned that included these was a 1981 Canadian-market electric
>> range. The last house I had that used these was the old house I had
>> in Canada from 1981-1983, and a new service entrance and breaker
>> panel were some of the first things I did to the house. My old house
>> in NY City lost these about 1965--it was originally built in 1921 and
>> had a single phase, three wire service entrance with two of the 30
>> Amp fuses as mains. The replacement had a two-pole 70 amp breaker. I
>> upgraded the 100 amp to 200 amp in my 1984-2004 house in California
>> and the house here came with a 200 A breaker panel.
>> These are not the best devices, but they certainly were pervasive.
>> The Fusetron fuses had diameters that were keyed to their ratings, so
>> you could not put in a different size once you screwed the adapter
>> into the "edison base" socket (same as a lamp). The adapters had
>> anti-removal pawls/springs so once the mod was done, it could not be
>> easily undone.
>> My 1921-built house had fuses in the neutrals as well as the hots!
>> I'm mentioning this on-list because there are many non-North-American
>> list members who might have a bit of curiosity about how domestic
>> sound reproducing equipment received its power--these were the
>> prevalent protection devices from before the 1920s into the 1950s.
>> On 2012-01-16 6:23 AM, Tom Fine wrote:
>>> All that you see here:
>>> yours for the price of shipping.
>>> Not sure if anyone uses these things anymore or if there are old
>>> equipment installs that use them??
>>> Ping off-list if interested.
>>> - -- Tom Fine
>> Richard L. Hess email: [log in to unmask]
>> Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX
>> Quality tape transfers -- even from hard-to-play tapes.
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