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Cooling of overloaded transformer

Started by Klaus Kragelund April 1, 2018
On Monday, April 2, 2018 at 12:44:15 PM UTC-4, Lasse Langwadt Christensen wrote:
> Den mandag den 2. april 2018 kl. 18.03.59 UTC+2 skrev George Herold: > > On Monday, April 2, 2018 at 10:56:46 AM UTC-4, mako...@yahoo.com wrote: > > > > > > > > modify the toaster to run on 230 with a diode in series with the > > > > heating element ? > > > > > > bzzzt wrong > > > > > > I'll let someone else explain why. > > > > > > mark > > > > Huh, well except for screwing up the power factor on the AC line, > > what's wrong with it? > > P = V^2/R > > I must have been low on coffee
Yeah I realized afterwards too. (just to lazy to post my mistake :^) GH
On 4/1/2018 6:12 PM, krw@notreal.com wrote:
> On Sun, 1 Apr 2018 15:15:45 -0700 (PDT), Klaus Kragelund > <klauskvik@hotmail.com> wrote: > >> On Sunday, April 1, 2018 at 9:07:26 PM UTC+2, Joseph Gwinn wrote: >>> On Apr 1, 2018, Klaus Kragelund wrote >>> (in article<6c166a81-64a7-4ed6-af8b-f79545106401@googlegroups.com>): >>> >>>> Hi >>>> >>>> When I go to the states, I usually buy white goods, half price than in Europe >>>> >>>> So I have a 600W 230V to 115V transformer installed in a cabinet >>>> >>>> Now I have bought a 1300W toaster >>>> >>>> Instead of buying a new transformer, I am seriously considering just >>>> overloading it, but then keeping the heat down by forced convection, namely a >>>> fan >>>> >>>> Anyone tried overloading transformers before? >>> >>> Won&rsquo;t really work, as others have said. My wife burn&rsquo;t her favorite hair >>> dryer out by forgetting to turn the swith from 115 to 230 on a trip some >>> years ago. Solution was to buy a local (European) hair dryer. >>> >>> I wouldn&rsquo;t think that toasters are so expensive (even in Europe) as to be >>> worth buying a big transformer. >>> >> By the way, it's only certain brands >> >> Kitchen Aid > > Have a kitchen full of KitchenAid appliances. > >> Festool tools > > ...and a basement full of those. ;-) > > Are they even more expensive than they are here? >> >> Whereas for example Garmin products are sometimes more expensive in the US even though the exchange rate US-DK has fallen by 15% the last year > > None of those. >
Keep your eye out for a junk tombstone welder and rewind the secondary. I have a transformer core that I've been saving for a project, I don't know what that project is yet! I also have a welder that someone threw in the trash after a fire on their boat, smoke damage not heat damage. I guess insurance bought them a new one. Heavy SOB's!
On Mon, 2 Apr 2018 09:44:11 -0700 (PDT), Lasse Langwadt Christensen
<langwadt@fonz.dk> wrote:

>Den mandag den 2. april 2018 kl. 18.03.59 UTC+2 skrev George Herold: >> On Monday, April 2, 2018 at 10:56:46 AM UTC-4, mako...@yahoo.com wrote: >> > > >> > > modify the toaster to run on 230 with a diode in series with the >> > > heating element ? >> > >> > bzzzt wrong >> > >> > I'll let someone else explain why. >> > >> > mark >> >> Huh, well except for screwing up the power factor on the AC line, >> what's wrong with it? > >P = V^2/R > >I must have been low on coffee
It would probably be OK at twice the normal power, quick toast, but the controls probably wouldn't work. -- John Larkin Highland Technology, Inc trk jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
George Herold <gherold@teachspin.com> wrote:

> On Monday, April 2, 2018 at 10:56:46 AM UTC-4, mako...@yahoo.com wrote: >> > >> > modify the toaster to run on 230 with a diode in series with the >> > heating element ?
>> bzzzt wrong
>> I'll let someone else explain why.
>> mark
> Huh, well except for screwing up the power factor on the AC line, > what's wrong with it?
P = E^2 / R
> George H. >
On Monday, 2 April 2018 21:08:05 UTC+1, John Larkin  wrote:
> On Mon, 2 Apr 2018 09:44:11 -0700 (PDT), Lasse Langwadt Christensen > <langwadt@fonz.dk> wrote: > >Den mandag den 2. april 2018 kl. 18.03.59 UTC+2 skrev George Herold: > >> On Monday, April 2, 2018 at 10:56:46 AM UTC-4, mako...@yahoo.com wrote:
> >> > > modify the toaster to run on 230 with a diode in series with the > >> > > heating element ? > >> > > >> > bzzzt wrong > >> > > >> > I'll let someone else explain why. > >> > > >> > mark > >> > >> Huh, well except for screwing up the power factor on the AC line, > >> what's wrong with it? > > > >P = V^2/R > > > >I must have been low on coffee > > It would probably be OK at twice the normal power, quick toast, but > the controls probably wouldn't work.
quick meltdown too.
On Monday, April 2, 2018 at 4:08:05 PM UTC-4, John Larkin wrote:
> On Mon, 2 Apr 2018 09:44:11 -0700 (PDT), Lasse Langwadt Christensen > <langwadt@fonz.dk> wrote: > > >Den mandag den 2. april 2018 kl. 18.03.59 UTC+2 skrev George Herold: > >> On Monday, April 2, 2018 at 10:56:46 AM UTC-4, mako...@yahoo.com wrote: > >> > > > >> > > modify the toaster to run on 230 with a diode in series with the > >> > > heating element ? > >> > > >> > bzzzt wrong > >> > > >> > I'll let someone else explain why. > >> > > >> > mark > >> > >> Huh, well except for screwing up the power factor on the AC line, > >> what's wrong with it? > > > >P = V^2/R > > > >I must have been low on coffee > > It would probably be OK at twice the normal power, quick toast, but > the controls probably wouldn't work.
With some counter you could pick every fourth pulse, maybe slosh it around and use a filter. The FEL use to pick AC pulses, 10Hz popular, but you could get any AC fractional period. George H.
> > > -- > > John Larkin Highland Technology, Inc trk > > jlarkin att highlandtechnology dott com > http://www.highlandtechnology.com
On Monday, April 2, 2018 at 4:11:00 PM UTC-4, Steve Wilson wrote:
> George Herold <gherold@teachspin.com> wrote: > > > On Monday, April 2, 2018 at 10:56:46 AM UTC-4, mako...@yahoo.com wrote: > >> > > >> > modify the toaster to run on 230 with a diode in series with the > >> > heating element ? > > >> bzzzt wrong > > >> I'll let someone else explain why. > > >> mark > > > Huh, well except for screwing up the power factor on the AC line, > > what's wrong with it? > > P = E^2 / R > > > George H. > >
If I ever get a new job description, I'll ask for a line about making mistakes... It's what I do best, well and making things work. Making 'em work is the fun bit. Mistakes are par for the course. George H.
On Mon, 2 Apr 2018 00:55:52 -0700 (PDT), Klaus Kragelund
<klauskvik@hotmail.com> wrote:

>On Monday, April 2, 2018 at 1:12:48 AM UTC+2, k...@notreal.com wrote: >> On Sun, 1 Apr 2018 15:15:45 -0700 (PDT), Klaus Kragelund >> <klauskvik@hotmail.com> wrote: >> >> >On Sunday, April 1, 2018 at 9:07:26 PM UTC+2, Joseph Gwinn wrote: >> >> On Apr 1, 2018, Klaus Kragelund wrote >> >> (in article<6c166a81-64a7-4ed6-af8b-f79545106401@googlegroups.com>): >> >> >> >> > Hi >> >> > >> >> > When I go to the states, I usually buy white goods, half price than in Europe >> >> > >> >> > So I have a 600W 230V to 115V transformer installed in a cabinet >> >> > >> >> > Now I have bought a 1300W toaster >> >> > >> >> > Instead of buying a new transformer, I am seriously considering just >> >> > overloading it, but then keeping the heat down by forced convection, namely a >> >> > fan >> >> > >> >> > Anyone tried overloading transformers before? >> >> >> >> Won&#2013266066;t really work, as others have said. My wife burn&#2013266066;t her favorite hair >> >> dryer out by forgetting to turn the swith from 115 to 230 on a trip some >> >> years ago. Solution was to buy a local (European) hair dryer. >> >> >> >> I wouldn&#2013266066;t think that toasters are so expensive (even in Europe) as to be >> >> worth buying a big transformer. >> >> >> >By the way, it's only certain brands >> > >> >Kitchen Aid >> >> Have a kitchen full of KitchenAid appliances. >> > >In Denmark, Kitchen Aid is considered top notch > >I have had to repair an older mixer before, with a worn worm drive gear. The toaster we had died, and I could not repair it. (was an intermittent problem, so difficult to locate). > >> >Festool tools >> >> ...and a basement full of those. ;-) >> >> Are they even more expensive than they are here? >> > > > >Festool products are the best, good German design > >Some are the same price, the plunge saws are almost the same price, probably due it's popularity > >The accessories are a half price, likewise with the cordless drills. The big miter saw is something like 30% off.
Half price here?
>The local Woodcraft store does not have the best price, so need to order online before going over there, so it has been delivered at the hotel
Huh? Festool regulates the price very tightly. They'll pull the franchise from anyone selling under their MSRP.
On 2018-04-01, tabbypurr@gmail.com <tabbypurr@gmail.com> wrote:
> On Sunday, 1 April 2018 20:15:56 UTC+1, Lasse Langwadt Christensen wrote: >> Den s&oslash;ndag den 1. april 2018 kl. 16.16.27 UTC+2 skrev Klaus Kragelund: >> > Hi >> > >> > When I go to the states, I usually buy white goods, half price than in Europe >> > >> > So I have a 600W 230V to 115V transformer installed in a cabinet >> > >> > Now I have bought a 1300W toaster >> > >> > Instead of buying a new transformer, I am seriously considering just overloading it, but then keeping the heat down by forced convection, namely a fan >> > >> > Anyone tried overloading transformers before? >> > >> > Regards >> > >> > Klaus >> >> modify the toaster to run on 230 with a diode in series with the >> heating element ? > > Double voltage quadruples power, diode only halves it > And the electronics wouldn't work, usually powered by a capacitor dropper.
Why wpuld they waste money on a capacitive dropper when for the price of a rivet they can have a resistive dropper? -- This email has not been checked by half-arsed antivirus software
On Tuesday, 3 April 2018 10:01:07 UTC+1, Jasen Betts  wrote:
> On 2018-04-01, tabbypurr wrote: > > On Sunday, 1 April 2018 20:15:56 UTC+1, Lasse Langwadt Christensen wrote: > >> Den s&oslash;ndag den 1. april 2018 kl. 16.16.27 UTC+2 skrev Klaus Kragelund: > >> > Hi > >> > > >> > When I go to the states, I usually buy white goods, half price than in Europe > >> > > >> > So I have a 600W 230V to 115V transformer installed in a cabinet > >> > > >> > Now I have bought a 1300W toaster > >> > > >> > Instead of buying a new transformer, I am seriously considering just overloading it, but then keeping the heat down by forced convection, namely a fan > >> > > >> > Anyone tried overloading transformers before? > >> > > >> > Regards > >> > > >> > Klaus > >> > >> modify the toaster to run on 230 with a diode in series with the > >> heating element ? > > > > Double voltage quadruples power, diode only halves it > > And the electronics wouldn't work, usually powered by a capacitor dropper. > > Why wpuld they waste money on a capacitive dropper when for the price > of a rivet they can have a resistive dropper?
You may well be right. NT