On 06/04/17 15:38, alister wrote:
> On Thu, 06 Apr 2017 12:36:25 +0000, Martin Gregorie wrote:
>
>> On Wed, 05 Apr 2017 22:33:00 -0400, rickman wrote:
>>
>>> On 4/5/2017 8:43 PM, Martin Gregorie wrote:
>>>> On Wed, 05 Apr 2017 18:28:00 +1200, Bill McGarrity wrote:
>>>>
>>>>> -=> rickman wrote to All on 04-05-17 17:07 <=-
>>>>>
>>>>>  ri> That is another smart thing the UK does.  In the US circuits are
>>>>>  ri> typically 15 amps which can safely be carried over 16 gauge
>>>>>  wire.
>>>>>  So ri> every device that plugs into an AC outlet uses 16 gauge wire
>>>>>  even if it ri> only draws less than an amp.
>>>>>
>>>>> US code for house wiring is 14 gauge for 15a circuits and 12 gauge
>>>>> for 20a service. Distance is also a factor in determining both wire
>>>>> gauge and service amps (600ft for 14/3 [15a] and 800ft for 12/3
>>>>> [20a]).
>>>>>
>>>> One thing that really worried me when I was living there was the way
>>>> cables to the more energy-intensive appliances heated up during normal
>>>> use when laid out across a floor. That was something I wasn't used to
>>>> feeling.
>>>>
>>>> Of course, 110v has a lot to answer for there: in the UK a 3kw heater
>>>> or power tool draws 12.5A, just under the 13A limit for standard
>>>> plugs,
>>>> but a 3kw appliance will draw 27.25A in the USA - and its amps, not
>>>> volts, that melts or burns insulation off a cable.
>>>
>>> In the US a 3 kW appliance will run on 240 volts.  We have 15 amp 120
>>> volt circuits normally and you can have a 20 amp 120 volt circuit with
>>> a slightly different socket which will also accept the 15 amp plugs,
>>> but they are not common.  If you need more than about 1.5 kW you use a
>>> 240 volt outlet with currents starting at 15 amp I believe.
>>
>> Fair comment, but I still remember those hot (above blood heat) cables
>> on vacuum cleaners and all the warnings about not leaving power cables
>> coiled up.
>
> the reason for not leaving cables coiled up is because if you do you have
> just created a large & inefficient transformer
>
>
>
No. it is because they melt. got through about three building the house
when people ran serious lights off them

Transformers with the return current in the same winding is the forward
current do not work, even as inductors.

--
The New Left are the people they warned you about.

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