DogMa > wrote:
>Mydnight wrote:
>> I got a Kamjove that I brought home from China last Christmas.
>> Unfortunately, they lied that it could convert the voltage. I had to
>> get a step-down transformer, a huge thing of about 20 pounds, just to
>> drink tea.
>
>Going the other way will usually lead to smoke and perhaps fire. But
>running a 220V passive heater (no control electronics) on 110V should be
>fine. It would nominally deliver 1/4 of the rated power. Since heating
>elements run so far above 100C, the water would still boil; it would
>just take about four times as long. Actually, the situation is better
>than that: the resistance of heating elements goes up at operating
>temperature. So at half-voltage, resistance is lower, current higher,
>and power not as much diminished.

Yes, but if it takes four times as long (and it actually is about that
because the increased heat loss during the longer warming time more than
makes up for the added heat due to the lower element resistance), that
sort of defeats the whole POINT of having an electric kettle, doesn't it?

>I wouldn't bother with a transformer; just change the plug if needed.

Problem is that a 1500W transformer is _big_ and _expensive_. It would be
easier and cheaper just to extend a 15A 220V line to your kitchen and
install a Europlug.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."