miércoles, 11 de junio de 2008
Induction Cooking: Makers and Products
http://www.nextag.com/bosch-cooktop/search-html
http://theinductionsite.com/makers.shtml
How to Sort the Heap
There are several ways in which one might organize a discussion of induction-cooking equipment and its makers. One might be geographic availability, for there is little point in reading about units you cannot obtain. But units not available in some one locale can often be ordered elsewhere, and--even with shipping, insurance, and customs costs added into the price--might be attractive packages. Another way to organize might be "commercial" versus "residential" units--save that many "residential" cooks like to use so-called "professional" level equipment. Yet another scheme might be to organize by type of equipment: true, integral cooktops (four or five elements in an integral housing); free-standing, one-element units (some meant for commercial catering use, others for tabletop residential use); drop-in modules (one- or two-element units intended for placement in custom kitchen-countertop designs); and so on.
What we have decided to do is to begin by presenting comprehensive, world-wide lists, after which we tabulate by major regions what makers' products seem available where.
You need to be aware that in the always (and rapidly) evolving world of "white goods" (as major apliances are known in the reade) all these data are necessarily snapshots of moving targets, and thus likely to be a bit blurred. We will strive mightily to keep up, but the pace of change these days is positively dizzying in this field, which is exciting but hectic. Always double- and triple-check anything you see here with the horse's mouth before making any crucial decisions. (But we didn't need to tell you that, did we?)
| Attention Induction-Appliance Makers! If you are associated with a maker of induction appliances and are reading this, ask yourself a question: whyever in the world would you dream that a consumer would want to spend substantial monies on a product that you, its maker, care so little about that you cannot be bothered to publish for it on your web site any of the most basic and critical statistics a purchaser might need to know to make an informed selection? Would you buy an automobile based on the information that it has four wheels and looks stylish? But you--most of you, anyway--seem to feel that consumers should buy your induction cooktops costing hundreds or thousands of dollars (or pounds) on the basis of information little if any more complete than that. Wake up and smell the coffee! Get your lazy corporate butts in gear and put some real information out for potential customers to see and evaluate. That is not "the retailer's job": it is your job--and if you don't want to bother with it, all we can assume is that your attitude is that you really don't care at all either about your products or about their potential buyers. As Lily Tomlin's famous line goes, we don't care--we don't have to. Well, we'll see . . . . . |
As you can deduce from that heartfelt message, most appliance makers are Not Real Good at putting out information. To begin with, it looks (whether so or not) as if they've all hired the same very, very, very, very, very bad web-site designer to assure that their site pages are difficult to navigate (and often so Flash-ridden as to be impossible to load at all, especially for those who eschew Microsoft products), arranged illogically and inconveniently, lack basic information, and are out of date, often wildly. Do these folk seriously believe that all a potential buyer wants and needs to know about a cooktop before spending the national budget of a third-world country on it is that it's black and shiny and has four cooking elements? Oh, maybe if they're feeling expansive, they'll tell you how wide the unit is. Boys and girls, those are not the rules by which the grownups play the game. Smart businessmen do not insult their customers' intelligence. OK?
| Important notes on these data:
(For much fuller information on power, read our page Kitchen Electricity 101.) |
Parallel Brands
Even to the inexperienced eye, it is obvious that not a few lines of induction equipment bear a suspicious resemblance ot other lines under other brand names--indeed, the name and logo on the unit often seems the only difference whatever. That is not mere parallel evolution at work: there is probably a definite connection between those parallel brands. One such connection is common ownership by an "appliance group" (that is, holding company); another is the use by one maker of "guts" (internal electronics) made by another company. Also, many "brands" are actually "outsourced" goods, meaning the so-called "maker" in fact just contracts out the making to another company and puts its own brand label on the product; sometimes the outsource maker will also make units under its own name and sometimes it is strictly a background manufacturer with no brands of its own. In any event, the point of note to the consumer is that many lines of induction equipment with substantially differing prices are in fact virtually identical: all you would be paying for in many cases is the "image" or feel-good quality that the brand projects, not the actual hardware.
Common Ownership
Knowing that Brand X and Brand Y are owned by the same paernt company does not mean that you can automatically treat their equipment lines as equivalent--but it is a useful thing to have in mind when balancing possible purchase choices' merits, especially when the products look and spec out with obvious parallelism.
Here, then, is a list, very probably incomplete, of who seems to own which brands. Brand names not on this list are either--we think--independents or are members of a group that makes no other induction equipment. The "group" links (in boldface) are to web-site pages of the groups themselves; the following by-brand links are each to the page of this site that deals with the brand in question. Keep in mind that some brands, whether subsidiaries on this list or nominal "independents", may use equipment made by some other company; we'll list some of those in a moment. This list is just ownership.
- Amica:
- BSH (Bosch Siemens Home Appliances):
- Candy:
- Electrolux:
- AEG
- Arthur Martin
- Dito [commercial]
- Electrolux
- Elco [commercial]
- Husqvarna
- Juno
- Molteni [commercial]
- Voss
- Zanussi
- Fagor:
- Glen Dimplex:
- Home Products:
- Indesit:
- Antonio Merloni: (not Merloni Elettrodomestici, which is now Indesit)
- Premium Appliance Brands:
- Teka:
- V-Zug:
- Bauknecht (Whirlpool appears to have discontinued this brand, which it now owns)
- Kitchenaid
- Whirlpool
Common Equipment
Some brands, though under distinctly different owners, may use hardware from some one source, necessarily making their lines quite similar. That arises because there are really only a few companies that have developed and maintain the actual technological and manufacturing capability of making induction equipment from the ground up. Some of those companies themselves market finished gear, while others remain in the background simply as suppliers to the known name labels. Here are the ones we think (no oaths taken) we have identified:
- Electrolux supplies:
- Fagor supplies:
- Diva de Provence (the residential units, not the commercial units)
- Heartland
- Kitchenaid
- Windcrest
- Luxine [no lines of its own] supplies:
- Jaeger Controls [no lines of its own] supplies:
- Spring supplies:
- Sunpentown (or it could be vice-versa: who owns the mark "Mr. Induction"?)
All Makers and Their Products
Here is a click-on/jump-to list of the data we have for each of the induction-cooker makers we know of. Each of our pages includes a link to the maker's own web site, as well as information on the maker and a list of all that maker's induction products (usually with full details on each).
Other related key resources on this site are our pages on:
- Selecting an Induction Unit (the important considerations involved in narrowing the field)
- Residential Build-In Database (lets you interactively identify units matching your available countertop space, kitchen wiring, and desired number of cooking zones)
- Residential Countertop Units (a compact list with cost/power merit figures from which you can select a unit to meet your needs)
- Commercial Units (a comprehensive induction-equipment tabulation for restaurants, buffet services, and other cooking professionals)
- Buying an Induction Unit (which tells you where you can buy units, including many you can buy from right here at the lowest prices around)
What Is Available Where
Obviously, not all makers' induction products are to be found in all nations or even regions. Moreover, within a given region--say "Europe"--a given maker may distribute a number of units that differ in variety and exact detail from nation to nation (in fact, that is common). So this guide is really only a top-level approximation of availability.
The sharpest divide is between Europe and North America, presumably owing to those regions' each having its own electrical codes and standards. Even though, in realistic and practical terms, any European unit will operate "as is" perfectly in North America, and vice versa (assuming only an appropriate supply voltage, and almost all major appliances run off 240-volt lines worldwide), a unit is not legal for sale or use till it has been certified by the appropriate authority for a given region. (Your tax dollars at work.)
Here is our best knowledge; outside North America and Europe, it is, we readily concede, spotty knowledge at best; we're trying to discover more.
Productos
http://www.wolfappliance.com/InductionCooktops
http://theinductionsite.com/
http://www.thermador.com/kitchen-appliances-cooking_cooktops_induction-cooktops.html
http://www.kuppersbuschusa.com/ElectricCooktops.asp
http://www.inductionsystems.com
http://www.inductionsystems.com/Merchant2/merchant.mv?Screen=CTGY&Store_Code=I&Category_Code=SUNI
http://www.freepatentsonline.com/result.html?query_txt=inductive%20cooktops
http://www.galtak.com/kyh30ap.html
http://www.current.com.au/news/article/DIQETASKZR
http://www.cooktek.com/product_info.php?p=1
Enlarge Image Featured Product - MagnaWave™ Heritage Single Counter Top Cooktop
 Spec Sheet Owner Manual |
Models MC1800 / MC2500 / MC3000 / MC3500
The classic CookTek® MC series counter top, single burner, induction cooktop offers outstanding performance and value for money. Designed and built in the USA to survive and thrive in the world’s toughest commercial foodservice operating environments. Simple one knob and one button control.
Features and Benefits
- Four models / four levels of power over two voltages to choose from.
- 100-120VAC and 200-240VAC versions.
- Worldwide plug options for 200-240VAC models.
- 0-20 Power settings or 80°F - 500°F (30°C - 260°C) temperature settings.
- Simple, familiar-feel control via single rotary knob and one button.
- Crisp, clean red LED display shows power level or temperature.
- Faster than gas. Induction heats the pan not the air or the unit itself.
- Safer. No flames, hot coil or other radiant hest source.
- Cleaner. Because the surface remains cool, spills don’t burn on.
- Cooler. No flame or radiant heat means a much cooler cooking environment.
- Cheaper. Induction cooking is over 90% efficient. Heat the food not the kitchen!
- Entela certified, NSF and CE approved.
Marcapasos Peligro
Confederación Suiza
Induction hobs
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The principle of induction cooking
Beneath each cooking zone of the induction hob there is a coil through which a medium-frequency alternating current (20 - 100 kHz) flows. This creates a magnetic field of the same frequency which passes unobstructed through the ceramic cover of the hob and penetrates the pan sitting on the cooking zone (Figure 1). The magnetic field creates a circular current in the electrically conductive base of the pan (eddy current). This principle is called induction. The base of the pan is made of a material in which the heat-loss of the eddy current is as high as possible at the frequency being used. This happens in ferromagnetic materials. In these materials the alternating field is forced into the outer layer of the pan base (skin effect), which increases the resistance of the material to the current and produces intense heat. The alternating magnetic field within the base of the pan also repeatedly magnetises and demagnetises the material, and this creates additional heat (hysteresis loss) [1].
Leakage current
Typical output
Regulating heating power
- Regulation using the frequency of the alternating current: The induction hob constitutes an electrical oscillating circuit which carries the maximum current at resonant frequency. If the frequency deviates from the resonant frequency, both current and output are reduced. (Example: full output at the resonant frequency of 17.5 kHz, output is four times lower at 41.7 kHz.)
- Regulation using pulse-amplitude modulation: Output is regulated by switching the magnetic field on and off periodically at lower cooking settings. One pulse every two seconds is typically used, with the duration of the pulse varying according to the selected output. The resulting magnetic fields are pulsed at a frequency of 0.5 Hz with varying pulse length.
Using several cooking zones at the same time
The measurements were carried out using appropriate and inappropriate pans which were centred over the cooking zone.
- Appropriate pans: Pans which are suitable for induction hobs AND whose diameter is the same as that of the cooking zone.
- Inappropriate pans: Pans which are not suitable for induction hobs OR whose diameter is not the same as that of the cooking zone.
The stray fields measured with inappropriate pans were up to 3.5 times larger than those measured with appropriate pans (Figure 2).
An induction hob switches off automatically when the pan is removed from the cooking zone. The stray-field measurements compared exactly centred pans with those which were only so far off-centre that the hob did not switch off. Figure 3 shows that positioning the pan off-centre increases the stray field for the same pan by a factor of up to 5.
Appropriate pan, centred vs. inappropriate pan, off-centre
Figure 4 compares the stray fields from an appropriate, centred pan and an unsuitable, off-centre pan (worst case). The stray fields in the worst case are up to 9.5 times larger than the stray field generated by the use according to the standard.
Stray fields are larger the closer to the cooking field they are measured. At a distance of 30 cm, all models comply with the reference value of 6.25 microtesla (µT) recommended by the ICNIRP. In most cases the stray field measured 1 cm in front of the edge of the cooking zone exceeds this reference value. With an off-centre placing the stray field reached the reference value at a distance of <>
Some studies have looked at the way induction hobs affect implanted electronic devices [7-10]. The possibility cannot be excluded that stray magnetic fields generated by induction hobs may affect implanted electronic devices at short range; this has been demonstrated for unipolar cardiac pacemakers [10]. Also the effect of leakage current on unipolar cardiac pacemakers has to be borne in mind. People with unipolar pacemakers are advised not to touch pans for extended periods and not to use metal spoons for cooking [7]. It is vital for people with implanted electronic devices to read the safety advice provided by the manufacturer and talk to their doctor before using an induction hob. The likelihood of the implanted device being affected adversely is very low if the induction hob is used correctly.
4. SN EN 50366 "Electromagnetic fields around household and similar electrical appliances – Methods for evaluation and measurement”
US Patent 6956188 - Induction heating coil with integrated resonant capacitor and method of fabrication thereof, and induction heating system employin
US Patent 6956188 - Induction heating coil with integrated resonant capacitor and method of fabrication thereof, and induction heating system employing the same
Links Inductive Ideas
http://ieeexplore.ieee.org/Xplore/login.jsp?url=/iel5/28/4157663/04157682.pdf?tp=&isnumber=&arnumber=4157682
Panasonic Cooktop
http://www.galtak.com/kyh30ap.html
Cocinar al wok
http://www.zealux.com/freestanding-induction-wok-cooktop-p-41.html