Author Topic: Converting an AC toaster to DC  (Read 13843 times)

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David HK

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Converting an AC toaster to DC
« on: August 13, 2009, 08:25:54 AM »
Curiosity has got the better of me and how would anyone convert a bog standard AC voltage toaster to 12 or 24 volts DC?


Does it make any difference to the taste?


Last of all how does one post in the Diaries Section? Another mystery for me.


David in HK

« Last Edit: August 13, 2009, 08:25:54 AM by (unknown) »

fungus

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Re: Converting an AC toaster to DC
« Reply #1 on: August 13, 2009, 04:27:10 AM »
I'm guessing it'd be possible by taking it apart, finding the right length of nichrome for whatever current you want on each section (for the right power for all of them added together), cut and splice somehow, then connect all together in parallel?

And to post in diaries look on the menu on the right hand side and look in the box under your name, 'new diary entry'.
« Last Edit: August 13, 2009, 04:27:10 AM by (unknown) »

David HK

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Re: Converting an AC toaster to DC
« Reply #2 on: August 13, 2009, 04:53:58 AM »
Fungus you have echoed my own thoughts.


It must be technically possible, but why have I never read about it being done before?


Maybe Tom, or Kurt, or Dan B, or the any of the other electronics whizz kids can illuminate an answer.


David HK

« Last Edit: August 13, 2009, 04:53:58 AM by (unknown) »

RogerAS

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Re: Converting an AC toaster to DC
« Reply #3 on: August 13, 2009, 05:03:54 AM »
Wouldn't an automotive cigarette lighter, unwound, be "just right" for a 12V toaster?


RS


(Not a whiz kid, not even a kid).

« Last Edit: August 13, 2009, 05:03:54 AM by (unknown) »

Flux

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Re: Converting an AC toaster to DC
« Reply #4 on: August 13, 2009, 06:48:19 AM »
Yes it could be done but messing about with lots of parallel bits of nichrome would be a daunting task. if you have the correct wire ( or better strip) and you have access to a spot welder then it would be possible. If you have to bolt all the joins then it will probably not be reliable in the long term. The various contacts will probably not handle the current at 12v so it will be very much a watch it and see situation and switch it off when the toast is ready.


In days when appliances were expensive we used to do things like this but the cost of common appliances is now so low that it is really a labour of love or time wasted. Inverters are relatively so cheap that it would make more sense to use a normal mains appliance. These things are cheap because they are made in millions, the present world is not geared to one off expensive things and there is always the stupid approvals that every appliance has to have to be sold these days.


Flux

« Last Edit: August 13, 2009, 06:48:19 AM by (unknown) »

kurt

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Re: Converting an AC toaster to DC
« Reply #5 on: August 13, 2009, 07:11:00 AM »
why on earth would you waste precious re electricity making toast get one of those Coleman stove top toast makers they work great my mother used one for years in our camper were we had no electricity except a 12v battery
« Last Edit: August 13, 2009, 07:11:00 AM by (unknown) »

jlt

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Re: Converting an AC toaster to DC
« Reply #6 on: August 13, 2009, 07:32:28 AM »
   I have seen a toaster oven in truck stops, that works on 12 volts. and you can cook a pizza with it .
« Last Edit: August 13, 2009, 07:32:28 AM by (unknown) »

scottsAI

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Re: Converting an AC toaster to DC
« Reply #7 on: August 13, 2009, 07:50:47 AM »
Why build when you can buy:

http://www.flyingjestore.com/index.cfm?fuseaction=showitem&PRODUCT_CODE=HD272&ITEM_NUMBER=2&
amp;SKU=100


Interesting write up about 12v appliances:

http://www.ccis.com/home/mnemeth/12volt/12volta.htm


To see what is available at 12v checkout:

http://www.rvsupplywarehouse.com/product/catalog.cfm/nid/230


Before today I had not visited any of the above links. YMMV.


Have fun,

Scott.

« Last Edit: August 13, 2009, 07:50:47 AM by (unknown) »

ghurd

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Re: Converting an AC toaster to DC
« Reply #8 on: August 13, 2009, 08:49:05 AM »
I saw a 12V toaster.  It pretty much just dehydrated the bread.


About the same idea as the 12V hair driers.  They make a lot of noise to give you something to think about while your hair dries at the same rate it would without the drier.


The items I saw were not high-end.  Hopefully something out there is better.


We just got a new toaster.  If the retail box is correct, it would take ~62A of 12V to operate the same as it does on 110AC.

G-

« Last Edit: August 13, 2009, 08:49:05 AM by (unknown) »
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Jerry

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Re: Converting an AC toaster to DC
« Reply #9 on: August 13, 2009, 08:53:54 AM »
Hi G.


It would seem then it would take even more amps the to operate that 110 volt toaster with an inverter. I don't think inverters are 100% eficient?


                         Jerry

« Last Edit: August 13, 2009, 08:53:54 AM by (unknown) »

Flux

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Re: Converting an AC toaster to DC
« Reply #10 on: August 13, 2009, 10:10:01 AM »
You can do anything at 12v if you are prepared to supply the current. Some things really aren't that practical. Heating appliances are best avoided if at all possible.


The smallest toaster is usually about 750W. It will take marginally more to run it with an inverter than one designed for 750W direct but for the time it is used it makes little difference.


I suspect those 12v things that claim to be toasters and pizza cookers aren't much over 100W. They may do the job, do it badly or not even do it, you would have to buy one to find out but generally these cheap 12v things are of little use. The little vacuum cleaners are virtually toys. For most things there is a fairly normal power consumption and if you try to go well below it the things don't work well.


On days when you have lots of power you can afford luxuries but kettles, toasters and similar things really tax a small low voltage system and it makes little difference whether you use an inverter or a specialist ( and probably expensive or useless) 12v device.


Ovens generally are a non event but the microwave does get the heat where you want it effectively and does the job quickly so running a kilowatt or so for a short time is not so bad.


I see friends with many gadgets that I find useless but I suppose they get pleasure from them and the manufacturers are more than happy to supply this market.


Cordless drills and a few other things have come a long way but most gadgets still need the same sort of power as they did long ago and the toaster is likely to be one of them.


Flux

« Last Edit: August 13, 2009, 10:10:01 AM by (unknown) »

Norm

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Re: Converting an AC toaster to DC
« Reply #11 on: August 13, 2009, 11:33:38 AM »
With a fresnel lens I can toast/burn my name on

a slice of bread....now one step further you would

take an old scanner and instead 'scan' a slice of

bread with the spot from a freznel lens going

thru an optical cable....would be entertaining

and a conversation piece.


    ( Oh Look....here's a light spot on the

toast where we had some clouds passing over)

   ( Why isn't that an image....why its its

Elvis Presley !)LOL

« Last Edit: August 13, 2009, 11:33:38 AM by (unknown) »

spinningmagnets

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Re: Converting an AC toaster to DC
« Reply #12 on: August 13, 2009, 12:09:52 PM »
On the short-lived TV series "Living with Ed" (Ed Begley Jr) he used a ped-gen to power a DC toaster each morning. No details about his specific components but his 20-minute morning exercise made one slice of organic whole-grain toast, to be covered with locally-grown no-sugar fruit spread.


Many web-posts about using a thrift-store bike and blender to make a pedal fruit-smoothie/margarita machine. Cut out the battery from the loop every chance you get....

« Last Edit: August 13, 2009, 12:09:52 PM by (unknown) »

tanner0441

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Re: Converting an AC toaster to DC
« Reply #13 on: August 13, 2009, 01:09:08 PM »
Hi


I have a mental picture of a modified toaster with a pair of 35mm2 cables feeding to the top of the work surface to carry the current. I have fitted several 12V microwaves to boats and 100A was the minimum we had to allow for. A 900W microwave is 900W into the cavity, the input power is nearer 1200W.  12 or 24W microwaves have the inverter built in. Magnetrons don't do much at 12V so it is 1200W plus inverter losses......


A 12V toaster is a none starter.


Brian

« Last Edit: August 13, 2009, 01:09:08 PM by (unknown) »

kurt

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Re: Converting an AC toaster to DC
« Reply #14 on: August 13, 2009, 01:20:17 PM »
a microwave magnetron needs 4000 volts dc to operate don't really matter if you start with 120v ac or 12v dc or whatever that is what you have to end up with to make the magnetron work.
« Last Edit: August 13, 2009, 01:20:17 PM by (unknown) »

David HK

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Re: Converting an AC toaster to DC
« Reply #15 on: August 13, 2009, 06:00:37 PM »
Who would have guessed that a simple toaster matter would have brought such interesting comments.


My impression is (rightly or wrongly) that in a renewable energy home of the future one can expect many appliances such as toasters, irons, televisions, microwaves, kettles, food blenders, ovens, water heaters et al to be powered via DC/AC inverters.


My original line of thinking was to consider what can be converted directly to 12, 24 or 48 volts DC to run directly off the battery supply without the need for an inverter.


David in

HK

« Last Edit: August 13, 2009, 06:00:37 PM by (unknown) »

Volvo farmer

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Re: Converting an AC toaster to DC
« Reply #16 on: August 13, 2009, 06:29:17 PM »
You have no wife huh? :-P
« Last Edit: August 13, 2009, 06:29:17 PM by (unknown) »
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boB

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Re: Converting an AC toaster to DC
« Reply #17 on: August 13, 2009, 08:21:07 PM »


  28 Volts, 400 Hz tastes best.


boB

« Last Edit: August 13, 2009, 08:21:07 PM by (unknown) »

dbcollen

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Re: Converting an AC toaster to DC
« Reply #18 on: August 13, 2009, 09:00:02 PM »
28.2 Volts is best, but 28.0 will suffice in a pinch.    :)
« Last Edit: August 13, 2009, 09:00:02 PM by (unknown) »

Flux

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Re: Converting an AC toaster to DC
« Reply #19 on: August 14, 2009, 12:39:34 AM »
You can't beat dielectric heating between two plates connected to a high frequency oscillator, it toasts from the inside outwards.


Flux

« Last Edit: August 14, 2009, 12:39:34 AM by (unknown) »

richhagen

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Re: Converting an AC toaster to DC
« Reply #20 on: August 14, 2009, 01:03:40 AM »
David,


I used a couple elements from a 120 VAC toaster as a dump load for a while.  A typical two slice toaster here has three elements, two on the outside that are wrapped on one side of a card, and one in the middle that is wrapped on both sides.  The two on the outsides are connected in series, and they are connected in parallel with the card in the middle.  


Splitting the outside cards and running them as a dump load on a 48V system (at about 56VDC) was about equivelant in terms of power, I tapped the middle element and with the outside cards ended up with four sections that would draw about 250 Watts each.  You could split up the elements to work on 12V and from the toasts perspective it would be equivelant.  


The control to pop it would be a bit more difficult.  It appeared to work by heating up slowly when about 8.3 amps went through it, causing it to slowly distort and ultimately cause the toast to pop.  I doubt it would work out too well with 83 amps DC unless you liked your toast rare, and even if you got arround that, the contacts would almost certainly be destroyed in short order switching that much current.  


You could cut the current load in half if you only wanted to toast one slice at a time.  Then you could use a 40 Amp DC breaker (I have one, and I think it costs more than a cheap toaster), or a bunch of FET's to switch the current, and you could build a circuit, maybe 555 Chip based, with a potentiometer to adjust the timer for how brown you wanted your toast.  


After all of that, you would still have to handle 40 amps to the toaster, which would require about size U.S. Guage 8 Wire.


While it could be done, I am not sure it that is where I would spend my time and energy on my system.  Rich

« Last Edit: August 14, 2009, 01:03:40 AM by (unknown) »
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richhagen

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Re: Converting an AC toaster to DC
« Reply #21 on: August 14, 2009, 01:16:17 AM »
note:  a 40 amp dc breaker wouldn't do much there, I meant a 40 amp solid state dc relay.  It's late and I am tired.  Rich
« Last Edit: August 14, 2009, 01:16:17 AM by (unknown) »
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bob golding

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Re: Converting an AC toaster to DC
« Reply #22 on: August 14, 2009, 04:59:24 AM »
as you live in HK i woud try a tracking solar concentrator  put a plate at the focus, and it would probably cook as fast as a conventional toaster. only one side at a time,and you would have to keep an eye on it,but it would work. google "solar cookers international" for more info. i have baked bread using a solar cooker even here in the UK summer.


bob golding

« Last Edit: August 14, 2009, 04:59:24 AM by (unknown) »
if i cant fix it i can fix it so it cant be fixed.

zap

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Re: Converting an AC toaster to DC
« Reply #23 on: August 14, 2009, 09:09:55 AM »
lol Norm

And if you decided you didn't want the toast... you could always sell any excess "Image of Elvis" toast and use the profit to buy more lenses and bread.

http://www.etsy.com/view_listing.php?ref=cat1_gallery_18&listing_id=17660808
« Last Edit: August 14, 2009, 09:09:55 AM by (unknown) »

Tritium

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Re: Converting an AC toaster to DC
« Reply #24 on: August 14, 2009, 11:37:36 AM »
Funny,  I used to use my heat gun at work to make toast. Did a great job. :)


Thurmond

« Last Edit: August 14, 2009, 11:37:36 AM by (unknown) »

dnix71

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Re: Converting an AC toaster to DC
« Reply #25 on: August 14, 2009, 06:36:54 PM »
Maybe you could do a cd burner laser mod to burn toast or jack up a handheld bar code scanner to do the job. You would need good eye protection against the scatter, though.
« Last Edit: August 14, 2009, 06:36:54 PM by (unknown) »

Old F

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Re: Converting an AC toaster to DC
« Reply #26 on: August 15, 2009, 06:49:51 AM »
Just be care full you could end up with something like this


http://www.youtube.com/watch?v=RZslRQvv5zM


Old F

« Last Edit: August 15, 2009, 06:49:51 AM by (unknown) »
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