On Wednesday, 18 May 2016 13:25:02 UTC+1, Dave Plowman (News) wrote:
In article ,
whisky-dave wrote:
On Tuesday, 17 May 2016 17:32:24 UTC+1, wrote:
On Tuesday, 17 May 2016 13:23:32 UTC+1, whisky-dave wrote:
On Friday, 13 May 2016 23:38:43 UTC+1, Rod Speed wrote:

enough to not make teh kettel 100% efficeint.
When the most efficint kettle the average consumer can buy is under 90%

I'm curious where you get that 90% from.

I didn;t it came up years ago (CSE physics I think) as being the most
efficient you can get from a demostic kettle. There's also quite a
differnce between hot water and bioling water.

Think you're confusing it with an electric motor.

Why are YOU confusing it with an electric motor, I'm not.

The amount of heat loss would be pretty consistent across a range of
element sizes.

across a smallish range I'd say.

Making a smaller element one very much more inefficient
than a large one.

yes I know.
Which is why reducing the power to a kettle won't make much sense.



A 3 kW kettle if 90% efficient would be losing 300 watts in heat. Lose the
same amount from a 1kW design, and it might take hours to boil.

Which is why it's be stupid to limit 3KW kettles to 1.5KW.

of course you might believe that a 3 watt kettle takes 1000 times longer to boil than a 3KW kettle you'd be wrong.

In article ,
Rod Speed wrote:
Because your kettle is adding **** to the water, most obviously the
scale.

You learn something new every day. The kettle makes the scale. It's not in
the water.

--
*DON'T SWEAT THE PETTY THINGS AND DON'T PET THE SWEATY THINGS.

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
whisky-dave wrote:
On Wednesday, 18 May 2016 13:25:02 UTC+1, Dave Plowman (News) wrote:
In article ,
whisky-dave wrote:
On Tuesday, 17 May 2016 17:32:24 UTC+1, wrote:
On Tuesday, 17 May 2016 13:23:32 UTC+1, whisky-dave wrote:
On Friday, 13 May 2016 23:38:43 UTC+1, Rod Speed wrote:

enough to not make teh kettel 100% efficeint.
When the most efficint kettle the average consumer can buy is under 90%

I'm curious where you get that 90% from.

I didn;t it came up years ago (CSE physics I think) as being the most
efficient you can get from a demostic kettle. There's also quite a
differnce between hot water and bioling water.

Think you're confusing it with an electric motor.

Why are YOU confusing it with an electric motor, I'm not.

Then you need to look up the efficiency of an electric kettle. It is
generally given as *better* than 90%. Not under 90%.

--
*Stable Relationships Are For Horses. *

Dave Plowman London SW
To e-mail, change noise into sound.

On 18/05/2016 14:18, whisky-dave wrote:
Which is why it's be stupid to limit 3KW kettles to 1.5KW.

How do you limit "3KW kettles to 1.5KW"? Use half the voltage?

--
Rod

In article ,
polygonum wrote:
On 18/05/2016 14:18, whisky-dave wrote:
Which is why it's be stupid to limit 3KW kettles to 1.5KW.

How do you limit "3KW kettles to 1.5KW"? Use half the voltage?

Think Dave may be guessing about what EU legislation may be proposed. The
theory being that because they have put an upper limit on the power
consumption of vacuum cleaners, they'll also do the same with kettles.
Makes a really good story for the meja to dribble spittle about. Same as
bent bananas.

--
*A journey of a thousand sites begins with a single click *

Dave Plowman London SW
To e-mail, change noise into sound.

On 18/05/2016 16:24, Dave Plowman (News) wrote:
Think Dave may be guessing about what EU legislation may be proposed.

Might well be guessing - but I was responding to the post as posted!

--
Rod

On 18/05/16 16:03, polygonum wrote:
On 18/05/2016 14:18, whisky-dave wrote:
Which is why it's be stupid to limit 3KW kettles to 1.5KW.

How do you limit "3KW kettles to 1.5KW"? Use half the voltage?

I guess. Half wave rectifier? Capacitor in series? Choke in series? have
to elements in parallel but use only one? Complicated SMPSU ?



--
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diverted our attention away from what really matters to our existential
survival, to indulging in navel gazing and faux moral investigations
into what the world ought to be, whilst we fail utterly to deal with
what it actually is.

In article ,
polygonum wrote:
On 18/05/2016 16:24, Dave Plowman (News) wrote:
Think Dave may be guessing about what EU legislation may be proposed.

Might well be guessing - but I was responding to the post as posted!

That's ever so rare on here. ;-)

--
*Succeed, in spite of management *

Dave Plowman London SW
To e-mail, change noise into sound.

"whisky-dave" wrote in message
...
On Wednesday, 18 May 2016 13:02:11 UTC+1, Rod Speed wrote:
"whisky-dave" wrote in message
...
On Tuesday, 17 May 2016 22:55:37 UTC+1, Rod Speed wrote:
whisky-dave wrote
Rod Speed wrote
whisky-dave wrote
Dave Plowman (News) wrote
whisky-dave wrote

When you switch a kettle off it doesn't stay boiling for very
long
does it.

No reason why it should - if you only boil enough for your
immediate
needs.

That can't be done

Even sillier than you usually manage.

I do that all the time, in the microwave, in the cup I will drink it
from.

That figures, I've rarley done it and for me the tastse is differnt.

Because your kettle is adding **** to the water, most obviously the
scale.

How does a kettle add scale to water ?

It always amazes me that people don't know what "action" it is that makes
the scale form.

It is (of course) leaving the unused water in the kettle as it evaporates,
not the fact that the water was heater up. The heating up just makes it
evaporate quicker.

I have a toothbrush mug that, because I leave it on the bathroom ledge to
dry every day scales up (albeit at a much slower rate) and the water in that
was never heated up, but you don't get scale on the inside of drinking
glasses because you wash and dry them after every use (or two).

tim

On 18/05/2016 19:16, tim... wrote:

How does a kettle add scale to water ?

It always amazes me that people don't know what "action" it is that
makes the scale form.

It is (of course) leaving the unused water in the kettle as it
evaporates, not the fact that the water was heater up. The heating up
just makes it evaporate quicker.

It appears that you don't know what action it is that makes the scale
form either.

It's heating up the water, driving off the CO2 from Ca(HCO3)2 to give
CaCO3 (insoluble) + H2O + CO2. Bicarbonate (soluble) - Carbonate
(insoluble).

You don't need to evaporate anything for that to happen.

Same chemistry as forms formations in caves, and the reverse of the
reaction which creates caves in the first place.

In message , Clive
George writes
On 18/05/2016 19:16, tim... wrote:

How does a kettle add scale to water ?

It always amazes me that people don't know what "action" it is that
makes the scale form.

It is (of course) leaving the unused water in the kettle as it
evaporates, not the fact that the water was heater up. The heating up
just makes it evaporate quicker.

It appears that you don't know what action it is that makes the scale
form either.

It's heating up the water, driving off the CO2 from Ca(HCO3)2 to give
CaCO3 (insoluble) + H2O + CO2. Bicarbonate (soluble) - Carbonate
(insoluble).

You don't need to evaporate anything for that to happen.

Same chemistry as forms formations in caves, and the reverse of the
reaction which creates caves in the first place.

I had thought stalagmites and -tites were due to rain droplets
collecting atmospheric carbon dioxide to form weak carbonic acid. This
dissolving calcium carbonate as it percolated through the soil and
re-depositing it due to evaporation in caves and my kettle.



--
Tim Lamb

"Clive George" wrote in message
...
On 18/05/2016 19:16, tim... wrote:

How does a kettle add scale to water ?

It always amazes me that people don't know what "action" it is that
makes the scale form.

It is (of course) leaving the unused water in the kettle as it
evaporates, not the fact that the water was heater up. The heating up
just makes it evaporate quicker.

It appears that you don't know what action it is that makes the scale form
either.

not the chemistry no, but I understand the physics


It's heating up the water, driving off the CO2 from Ca(HCO3)2 to give
CaCO3 (insoluble) + H2O + CO2. Bicarbonate (soluble) - Carbonate
(insoluble).

I think that's nit picking.

so something changes from soluble to insoluble, but if the water evaporates
away even the soluble stuff will solidify out

tim

On 18/05/2016 11:33, whisky-dave wrote:
On Tuesday, 17 May 2016 22:55:37 UTC+1, Rod Speed wrote:


As I said, what gets lost in the boiling is a trivial part

No it isn;t because to boil water you need to put in a lot of energy,
something to do with the latent heat of evaporation.

Hmm, 180 seconds @3kw to get to boiling, two seconds @3kw for the auto
shut off makes the boiling bit trivial.

On Wednesday, 18 May 2016 11:04:12 UTC+1, whisky-dave wrote:
On Tuesday, 17 May 2016 17:32:24 UTC+1, tabbypurr wrote:
On Tuesday, 17 May 2016 13:23:32 UTC+1, whisky-dave wrote:
On Friday, 13 May 2016 23:38:43 UTC+1, Rod Speed wrote:

enough to not make teh kettel 100% efficeint.
When the most efficint kettle the average consumer can buy is under 90%

I'm curious where you get that 90% from.

I didn;t it came up years ago (CSE physics I think) as being the most efficient you can get from a demostic kettle.
There's also quite a differnce between hot water and bioling water.

I figured you wouldn't provide a basis for it.


NT

On Wednesday, 18 May 2016 11:33:15 UTC+1, whisky-dave wrote:
On Tuesday, 17 May 2016 22:55:37 UTC+1, Rod Speed wrote:

As I said, what gets lost in the boiling is a trivial part

No it isn;t because to boil water you need to put in a lot of energy,
something to do with the latent heat of evaporation.

Energy input is constant at 2.4-3.1kW. 2 minutes heating then 6 seconds boiling means apx 6/120 = 5% of the energy input went into boiling.


NT

On Wed, 18 May 2016 16:03:34 +0100, polygonum wrote:

On 18/05/2016 14:18, whisky-dave wrote:
Which is why it's be stupid to limit 3KW kettles to 1.5KW.

How do you limit "3KW kettles to 1.5KW"? Use half the voltage?

You obviously put a resistor in series.




--
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wish to copy them they can pay me £1 a message.
Use the BIG mirror service in the UK: http://www.mirrorservice.org
*lightning surge protection* - a w_tom conductor

On 18/05/2016 21:09, Bob Eager wrote:
On Wed, 18 May 2016 16:03:34 +0100, polygonum wrote:

On 18/05/2016 14:18, whisky-dave wrote:
Which is why it's be stupid to limit 3KW kettles to 1.5KW.

How do you limit "3KW kettles to 1.5KW"? Use half the voltage?

You obviously put a resistor in series.


I see! To make a mug of tea you put half the water in each kettle and
wire them in series with each other! Brilliant. Don't need new kettles,
just a quick change of wiring.

--
Rod

On 18/05/2016 20:39, tim... wrote:

"Clive George" wrote in message
...
On 18/05/2016 19:16, tim... wrote:

How does a kettle add scale to water ?

It always amazes me that people don't know what "action" it is that
makes the scale form.

It is (of course) leaving the unused water in the kettle as it
evaporates, not the fact that the water was heater up. The heating up
just makes it evaporate quicker.

It appears that you don't know what action it is that makes the scale
form either.

not the chemistry no, but I understand the physics


It's heating up the water, driving off the CO2 from Ca(HCO3)2 to give
CaCO3 (insoluble) + H2O + CO2. Bicarbonate (soluble) - Carbonate
(insoluble).

I think that's nit picking.

so something changes from soluble to insoluble, but if the water
evaporates away even the soluble stuff will solidify out

It's not really nit picking. The important point is you don't need
evaporation to get scale.

Yes, if you boiled off the water you'd get the same deposit. But you
don't need to boil it off to do that either.

Dave Plowman (News) wrote
whisky-dave wrote
wrote
whisky-dave wrote
Rod Speed wrote

enough to not make teh kettel 100% efficeint.

When the most efficint kettle the average consumer can buy is under 90%

I'm curious where you get that 90% from.

I didn;t it came up years ago (CSE physics I think) as being the
most efficient you can get from a demostic kettle. There's also
quite a differnce between hot water and bioling water.

Think you're confusing it with an electric motor.

The amount of heat loss would be pretty
consistent across a range of element sizes.

The bulk of the heat loss has nothing to do with the
element sizes, it is due to the kettle boiling the water
for longer than necessary after the water starts boiling.

Making a smaller element one very much
more inefficient than a large one.

Only a little less efficient because the kettle takes
more time to boil the water and so loses more heat
by radiation from the body of the kettle because it
is radiating longer.

A 3 kW kettle if 90% efficient would be losing 300 watts in heat. Lose
the same amount from a 1kW design, and it might take hours to boil.

You've mangled that utterly too. They would both be 90% efficient
if Dave-the-sot's story is correct, and so the 1KW design would only
take 3 times as long to boil the kettle.

"whisky-dave" wrote in message
...
On Wednesday, 18 May 2016 12:47:15 UTC+1, Rod Speed wrote:
"whisky-dave" wrote in message
...
On Tuesday, 17 May 2016 17:32:24 UTC+1, wrote:
On Tuesday, 17 May 2016 13:23:32 UTC+1, whisky-dave wrote:
On Friday, 13 May 2016 23:38:43 UTC+1, Rod Speed wrote:

enough to not make teh kettel 100% efficeint.
When the most efficint kettle the average consumer can buy is under
90%

I'm curious where you get that 90% from.

I didn;t it came up years ago (CSE physics I think) as being
the most efficient you can get from a demostic kettle.

Just because some fool claims something.

just because some fool thinks kettles are 100% effecient doesn;t mean they
are.


That number is complete and utter drivel
and it is completely trivial to prove that.

So prove it.

Get ****ed.

That figure was the text books guide to the most efficient type of the
time

That's a lie. It was in fact straight from someone's arse, you can tell from
the smell.

when the book was publish which I think was in the 1970s,

It wasnt even true then. The efficiency of a kettle mostly depends
on how long it is left to boil for once the water in it is boiling. That
is nothing even remotely like 90% with the best kettle use.

they also said that an average bolt of lightning
could power London for 20-30 seconds.

That number is straight from their arse too.

No one has ever been able to measure
the power of an average bolt of lightning.

reams of your **** flushed where it belongs

Electric kettles are designed for their efficiency

**** all of them are. They are in fact designed to be
cheap to make and the efficiency doesnt change
much with big variations in the design except for
how quickly they turn off when the water has boiled.

and many of them have names like Eco Kettle.

The GDR claimed to be democratic too.

In electric kettles the water is in direct contact with the heating
element,

Yes, but that isnt what determines its efficiency.

there is no pot to heat and most kettles include an integrated lid.
The electric kettle averaged around 1200 watts and took 125
seconds to boil the water, which translates to 0.04 kilowatt-hours
(kWh) of electricity consumed. I cleared the cobwebs off of the
thermodynamic part of my brain

Ear to ear dog **** doesnt have cobwebs, spiders won't go near it.

and calculated that the theoretical energy required to
heat 350 ml of water by 83° C in 125 seconds is 972 watts.

Maybe.

Dividing this by the actual wattage used gives us the
overall efficiency of boiling water in an electric kettle,

Wrong, as always.

81%.

The efficiency of an electric kettle is in fact determined by
how long it continues to boil the water after it has started
to boil, stupid, because that is the main way they lose heat.

"polygonum" wrote in message
...
On 18/05/2016 14:18, whisky-dave wrote:
Which is why it's be stupid to limit 3KW kettles to 1.5KW.

How do you limit "3KW kettles to 1.5KW"? Use half the voltage?

It's easy, you use twice the water and brew the tea for the neighbour as
well.

"whisky-dave" wrote in message
...
On Wednesday, 18 May 2016 13:02:11 UTC+1, Rod Speed wrote:
"whisky-dave" wrote in message
...
On Tuesday, 17 May 2016 22:55:37 UTC+1, Rod Speed wrote:
whisky-dave wrote
Rod Speed wrote
whisky-dave wrote
Dave Plowman (News) wrote
whisky-dave wrote

When you switch a kettle off it doesn't stay boiling for very
long
does it.

No reason why it should - if you only boil enough for your
immediate
needs.

That can't be done

Even sillier than you usually manage.

I do that all the time, in the microwave, in the cup I will drink it
from.

That figures, I've rarley done it and for me the tastse is differnt.

Because your kettle is adding **** to the water, most obviously the
scale.

How does a kettle add scale to water ?

By having it in the kettle when it boils the water.

As I said yuo always have to biol more water than you
need for the cup or vessel you wish to drink from.

As I said, what gets lost in the boiling is a trivial part

No it isn;t because to boil water you need to put in a lot of energy,
something to do with the latent heat of evaporation.

I wasnt talking about the energy there, just the water that gets lost.

I dont; care about the water it's cheap it;s the
electricity that costs the money when boiling it.

The water was being discussed before you did your usual red herring.

I don;t care if I 'lose' a few ml of water it's virtually free as I
have unmeterred water and DO NOT have unmetered electricity.

See above.

as I said you need more water in the kettle than you are planing on
drinking.

And you need **** all more than you are planning on drinking
when you heat it in the microwave in the vessel you will be
drinking it from.

But that's not as quick or as effcient and the cups handle gets hot too

No it doesnt with a proper mug.

and I dont like the taste of re-heated tea.

No tea is reheated.

https://www.quora.com/Does-reheating...ange-its-taste

You dont reheat tea, you heat water and add the tea bag once its heated.

reams of your irrelevant **** flushed where it belongs

I use a cordless kettle, so if I want to make one cup of tea I get the
mug
I will use fill that with water and put that in the kettle then boil
it.
If I want two mugs I put two mugs of water in ... see how this works
could you work out how many mugs of water I'd put in my kettle if
I wanted to make 3 cups of tea. ?

Too much farting around. Makes more sense to mark the kettle which
has a proper gauge on the side with where you need to fill it for the
number of mugs of water you do often.

but then I have to take the kettle to the sink,

You have to take something to the sink, stupid.

what usualy happens in that I wash my mug/cup
with warm water, fill it with cold them empty it
into the kettle then switch the kettle on.

Makes a lot more sense to put the mug in
the microwave when filled with cold water.

Seems simple enough.

This **** below clearly is nothing like that.

Now remmeber what I said about adding more water than you will be
drinking....
So when I fill a mug up with water there's is more water in that mug
than
there will be when the water is HOT. Because :-
1/ because of the volume of the tea bag I can't get the same amount of
water in there plus tea bag..
2 I have milk so when emptying the boiling water in to teh mug
containing the teabag I have to leave about ~15% from the top lip so I
can
put the milk in.
3/ I also allow for stiring & sugar so again I don;t fill the cup up
with
hot water.
4/ I have to carry it from one room to the next so again I don't fill
the
mug up with hot water+milk.
5/ another reason I take the water to the kettle rather than the kettle
to
the water is because my previous kettle became fault due o the central
connection bit it seemd to fail before the eliment and on a few
occasions
sparked.

None of that **** when you heat the water in the
mug in the microwave and drink coffee instead of tea.

As I said I don't like nuked tea,

Because you are stupid enough to prefer the **** the kettle adds.

nuked coffee isn't as bad.
But I don't like a cup with a hot handle.

Dont get a hot handle.

It also seemed to take longer in the mircowave than the ketkle.

Then you need a better microwave.

teh more steam that comes out teh lower the effeciancy

So you have a kettle which stops heating as soon as any steam comes out.

Well it switches itself off when boiling something a microwave oven can't
do.

Wrong, as always. The better microwaves do just that.

Not exactly rocket science.

Microwave ovens can't do it.

Wrong, as always.

and the more it is costing for that cup of tea,

Not with a properly designed kettle.

Yep even bably designed kettle are better at heating water,

Wrong, as always.

all your **** flushed where it belongs

"whisky-dave" wrote in message
...
On Wednesday, 18 May 2016 13:25:02 UTC+1, Dave Plowman (News) wrote:
In article ,
whisky-dave wrote:
On Tuesday, 17 May 2016 17:32:24 UTC+1, wrote:
On Tuesday, 17 May 2016 13:23:32 UTC+1, whisky-dave wrote:
On Friday, 13 May 2016 23:38:43 UTC+1, Rod Speed wrote:

enough to not make teh kettel 100% efficeint.
When the most efficint kettle the average consumer can buy is under
90%

I'm curious where you get that 90% from.

I didn;t it came up years ago (CSE physics I think) as being the most
efficient you can get from a demostic kettle. There's also quite a
differnce between hot water and bioling water.

Think you're confusing it with an electric motor.

Why are YOU confusing it with an electric motor, I'm not.

The amount of heat loss would be pretty consistent across a range of
element sizes.

across a smallish range I'd say.

Making a smaller element one very much more inefficient
than a large one.

yes I know.
Which is why reducing the power to a kettle won't make much sense.

That isnt about efficiency, its about limiting the peak demand
on the grid when all you fools watching the big match etc all
decide to put the kettle on in the same ad break.

A 3 kW kettle if 90% efficient would be losing 300 watts in heat. Lose
the
same amount from a 1kW design, and it might take hours to boil.

Which is why it's be stupid to limit 3KW kettles to 1.5KW.

Nope.

of course you might believe that a 3 watt kettle takes 1000 times longer
to boil than a 3KW kettle you'd be wrong.

Dave Plowman (News) wrote
Rod Speed wrote:

Because your kettle is adding **** to the water, most obviously the
scale.

You learn something new every day. The kettle makes the scale.

Never said that, ****wit.

It's not in the water.

Its obviously in the water when you heat it the mug in the microwave,
but even a terminal ****wit such as yourself should realise that when
you heat the water in a scaled up kettle, some of that ends up in the
water too, particularly with the element.

Trivially easy to measure that too.

In article ,
Rod Speed wrote:
The bulk of the heat loss has nothing to do with the
element sizes, it is due to the kettle boiling the water
for longer than necessary after the water starts boiling.

Civilised countries have kettles that switch off on boiling. You'll
probably get them some day.

--
*Most people have more than the average number of legs*

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
Rod Speed wrote:
Its obviously in the water when you heat it the mug in the microwave,
but even a terminal ****wit such as yourself should realise that when
you heat the water in a scaled up kettle, some of that ends up in the
water too, particularly with the element.

Odd that. If the scale is being deposited inside the kettle from the
water, it somehow adds to fresh water in the kettle?

Congratulations. You've invented the creation of material out of nothing.

--
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Dave Plowman London SW
To e-mail, change noise into sound.

On 12/05/2016 20:07, Steve Walker wrote:
On 12/05/2016 11:48, Tim Streater wrote:
In article ,
wrote:

It would be a bit extreme to see the steering wheel move from right to
left
halfway through the channel tunnel though ...

You'd have to exchange the front seat passengers too.

Not if they can drive too. Great way to share the driving!

More seriously. It is surely reaching the stage of reliability now
(especially if we are thinking of self-driving cars even being allowed
on the roads) that we could dispense with a physical connection for
steering and actually have cars and trucks that you could unclip the
controls from and swap to the other side?

Around the turn of the century I was working on a traffic / road
information system that a consortium of firms were developing... That
included what (superficially at least) looked like a normal Jag XJ8 (if
you ignored to 40 odd cameras pointing out of it and the boot absolutely
full of electronics), but it was completely drive by wire - the
connection between pedals, and the steering wheel was all communicated
to the mechanics via a dedicated high priority CAN bus, and no physical
linkages.



--
Cheers,

John.

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On 12/05/2016 16:38, whisky-dave wrote:
On Thursday, 12 May 2016 15:18:09 UTC+1, Tim Watts wrote:
On 12/05/16 10:47, Brian Gaff wrote:

As for kettles, I do think more efficent kettles can be made, the basic
designs have not changed since the 1950s.

How? 99% of the energy goes into the water with a tiny tiny bit lost in
the lead and through the case.

Have you every heard or seen steam come out of teh spout.
Have you ever touched the side of a kettle.

When you switch a kettle off it doesn't stay boiling for very long does it.

That might be the requirement for 2.2MJ of energy for every kg of water
converted to steam!


--
Cheers,

John.

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Dave Plowman (News) wrote
Rod Speed wrote

The bulk of the heat loss has nothing to do with the
element sizes, it is due to the kettle boiling the water
for longer than necessary after the water starts boiling.

Civilised countries have kettles that switch off on boiling.

But how quickly they do that clearly does affect their efficiency, ****wit.

Dave Plowman (News) wrote
Rod Speed wrote

Its obviously in the water when you heat it the mug in the microwave,
but even a terminal ****wit such as yourself should realise that when
you heat the water in a scaled up kettle, some of that ends up in the
water too, particularly with the element.

Odd that.

Nope.

If the scale is being deposited inside the kettle from the water,

Because the CO2 is driven out of the bicarbonate producing
the carbonate which is what the scale is, ****wit.

it somehow adds to fresh water in the kettle?

Of course some of the carbonate/scale gets into
the water when it is heated in a kettle, ****wit.

Congratulations. You've invented the creation of material out of nothing.

Thanks for that completely superfluous proof that you
have never had a ****ing clue about anything at all, ever.

On Thu, 19 May 2016 00:26:45 +0100, "Dave Plowman (News)"
wrote:

In article ,
Rod Speed wrote:
The bulk of the heat loss has nothing to do with the
element sizes, it is due to the kettle boiling the water
for longer than necessary after the water starts boiling.

Civilised countries have kettles that switch off on boiling. You'll
probably get them some day.

Hope not,

"Once a jolly swagman camped by a billabong
Under the shade of a coolibah tree,
And he sang as he watched and waited till his electric kettle boiled
"Who'll come a-waltzing Matilda, with me?"

Just doesn't sound the same.

G.Harman

On 18/05/16 21:34, polygonum wrote:
On 18/05/2016 21:09, Bob Eager wrote:
On Wed, 18 May 2016 16:03:34 +0100, polygonum wrote:

On 18/05/2016 14:18, whisky-dave wrote:
Which is why it's be stupid to limit 3KW kettles to 1.5KW.

How do you limit "3KW kettles to 1.5KW"? Use half the voltage?

You obviously put a resistor in series.


I see! To make a mug of tea you put half the water in each kettle and
wire them in series with each other! Brilliant. Don't need new kettles,
just a quick change of wiring.

Now that solution is along the liness of 'how do you measure the height
of a tower block with a barometer' 'Drop the barometer of the tower
block and measure how long it takes to hit the ground' school of thinking.

Love it!

--
How fortunate for governments that the people they administer don't think.

Adolf Hitler

On 18/05/16 22:58, Tim Streater wrote:
In article , tim...
wrote:

"Clive George" wrote in message
...
On 18/05/2016 19:16, tim... wrote:

How does a kettle add scale to water ?

It always amazes me that people don't know what "action" it is that
makes the scale form.

It is (of course) leaving the unused water in the kettle as it
evaporates, not the fact that the water was heater up. The heating up
just makes it evaporate quicker.

It appears that you don't know what action it is that makes the scale
form either.

not the chemistry no, but I understand the physics


It's heating up the water, driving off the CO2 from Ca(HCO3)2 to give
CaCO3 (insoluble) + H2O + CO2. Bicarbonate (soluble) - Carbonate
(insoluble).

I think that's nit picking.

so something changes from soluble to insoluble, but if the water
evaporates away even the soluble stuff will solidify out

I haven't actually checked, but I suspect the carbonate is *slightly*
soluble. So the heating creates it and evaporation (either from the
heating or not) causes it to solidify out.

No. What happens is that heat causes the reaction already mentioned -
from bi carbonate to carbonate plus CO2 - to accelerate.

AS the stalactites show, that reaction always happens even at low temps,
but its massively accelerated at high ones..




Perhaps that's why CH pipes (a) get scaled and (b) need bleeding from
time to time.



--
How fortunate for governments that the people they administer don't think.

Adolf Hitler

On Wednesday, 18 May 2016 16:03:36 UTC+1, polygonum wrote:
On 18/05/2016 14:18, whisky-dave wrote:
Which is why it's be stupid to limit 3KW kettles to 1.5KW.

How do you limit "3KW kettles to 1.5KW"? Use half the voltage?

yes you stick a diode in it, so you only use ~half the cycle.
This would be a cheap way for changing the power of a kettle over the net
if you wanted to reduce peak load.
Now considering a student has just left me after demoing his hairbrush that moves towards the light don't tell me that what's happening in IoT.





--
Rod

On Wednesday, 18 May 2016 16:24:57 UTC+1, Dave Plowman (News) wrote:
In article ,
polygonum wrote:
On 18/05/2016 14:18, whisky-dave wrote:
Which is why it's be stupid to limit 3KW kettles to 1.5KW.

How do you limit "3KW kettles to 1.5KW"? Use half the voltage?

Think Dave may be guessing about what EU legislation may be proposed.

Not neccesarily EU.



theory being that because they have put an upper limit on the power
consumption of vacuum cleaners, they'll also do the same with kettles.

Well who wants a 5KW kettle ?
well when we have functions here we often have nore than one kettle
to heat water sometimes we have one for coffee and one for tea :-0


In our research areas we often have 1-6 studetns in a room using their own kettles, which is why we or rather the college H&S don't like us using those plugs with two IEC connectors on them, just in case someone plugs two kettles in the the same wall socket.



Makes a really good story for the meja to dribble spittle about. Same as
bent bananas.

and we all know there's no plans for smartmeters to to anything other than record don't we.
And they'll be no way a meter will be able to limit what current passes through bit other than if the fuse blows.

On 19/05/2016 12:33, whisky-dave wrote:
On Wednesday, 18 May 2016 16:24:57 UTC+1, Dave Plowman (News)
wrote:
In article , polygonum
wrote:
On 18/05/2016 14:18, whisky-dave wrote:
Which is why it's be stupid to limit 3KW kettles to 1.5KW.

How do you limit "3KW kettles to 1.5KW"? Use half the voltage?

Think Dave may be guessing about what EU legislation may be
proposed.

Not neccesarily EU.



theory being that because they have put an upper limit on the
power consumption of vacuum cleaners, they'll also do the same with
kettles.

Well who wants a 5KW kettle ? well when we have functions here we
often have nore than one kettle to heat water sometimes we have one
for coffee and one for tea :-0


In our research areas we often have 1-6 studetns in a room using
their own kettles, which is why we or rather the college H&S don't
like us using those plugs with two IEC connectors on them, just in
case someone plugs two kettles in the the same wall socket.

Surely the dual iec connectors are "cold" connectors (no notch) and
kettles use "hot" connectors (with a notch)? You can plug a computer in
using a kettle lead, but you cannot physically plug a kettle in using a
computer lead.

On 18/05/2016 23:30, Rod Speed wrote:


"whisky-dave" wrote in message
...
On Wednesday, 18 May 2016 13:25:02 UTC+1, Dave Plowman (News) wrote:
In article ,
whisky-dave wrote:
On Tuesday, 17 May 2016 17:32:24 UTC+1, wrote:
On Tuesday, 17 May 2016 13:23:32 UTC+1, whisky-dave wrote:
On Friday, 13 May 2016 23:38:43 UTC+1, Rod Speed wrote:

enough to not make teh kettel 100% efficeint.
When the most efficint kettle the average consumer can buy is
under 90%

I'm curious where you get that 90% from.

I didn;t it came up years ago (CSE physics I think) as being the most
efficient you can get from a demostic kettle. There's also quite a
differnce between hot water and bioling water.

Think you're confusing it with an electric motor.

Why are YOU confusing it with an electric motor, I'm not.

The amount of heat loss would be pretty consistent across a range of
element sizes.

across a smallish range I'd say.

Making a smaller element one very much more inefficient
than a large one.

yes I know.
Which is why reducing the power to a kettle won't make much sense.

That isnt about efficiency, its about limiting the peak demand
on the grid when all you fools watching the big match etc all
decide to put the kettle on in the same ad break.

But some will put the kettle on immediately, some will nip to the toilet
first, etc. so the demand is spread through the ad break. Lower the
power, so they take longer to boil, and you'll just end up with a point
where the early ones are still on and the late ones have turned on,
possibly giving an even bigger peak load.

On 19/05/2016 05:31, Rod Speed wrote:
Dave Plowman (News) wrote
Rod Speed wrote

The bulk of the heat loss has nothing to do with the
element sizes, it is due to the kettle boiling the water
for longer than necessary after the water starts boiling.

Civilised countries have kettles that switch off on boiling.

But how quickly they do that clearly does affect their efficiency, ****wit.

And if you make it react very quickly, you increase the sensitivity and
make it liable to false tripping. People will simply return kettles as
not fit for purpose if they regularly cut-off too soon or even worse,
cut-off and won't reset for some time.

On Thu, 19 May 2016 22:44:45 +0100, Steve Walker
wrote:

On 19/05/2016 12:33, whisky-dave wrote:

In our research areas we often have 1-6 studetns in a room using
their own kettles, which is why we or rather the college H&S don't
like us using those plugs with two IEC connectors on them, just in
case someone plugs two kettles in the the same wall socket.

Surely the dual iec connectors are "cold" connectors (no notch) and
kettles use "hot" connectors (with a notch)? You can plug a computer in
using a kettle lead, but you cannot physically plug a kettle in using a
computer lead.

You can get kettles which take a cold connector. Either they are
better insulated or the manufacturers are cheapskates.

"whisky-dave" wrote in message
...
On Wednesday, 18 May 2016 16:24:57 UTC+1, Dave Plowman (News) wrote:
In article ,
polygonum wrote:
On 18/05/2016 14:18, whisky-dave wrote:
Which is why it's be stupid to limit 3KW kettles to 1.5KW.

How do you limit "3KW kettles to 1.5KW"? Use half the voltage?

Think Dave may be guessing about what EU legislation may be proposed.

Not neccesarily EU.



theory being that because they have put an upper limit on the power
consumption of vacuum cleaners, they'll also do the same with kettles.

Well who wants a 5KW kettle ?
well when we have functions here we often have nore than one kettle
to heat water sometimes we have one for coffee and one for tea :-0


In our research areas we often have 1-6 studetns in a room using their own
kettles, which is why we or rather the college H&S don't like us using
those plugs with two IEC connectors on them, just in case someone plugs
two kettles in the the same wall socket.



Makes a really good story for the meja to dribble spittle about. Same as
bent bananas.

and we all know there's no plans for smartmeters to to anything other than
record don't we.
And they'll be no way a meter will be able to limit what current passes
through bit other than if the fuse blows.

Just how are you claiming the smart meter will be able to
limit the current other than just turning it off completely ?

If the smart meters were capable of doing that, it would
be obvious from an inspection of the meter.