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Moving magnets generate a changing magnetic field, coils generate current.
So, how to produce a change of magnetic field? One way is to use the change of electric field.
Our households using alternating current, the size and direction of changes with time frequency is 50 Hz,
is a second change of 50 cycles.
The principle of the electromagnetic oven is first 50 Hz alternating current into direct current,
again after control circuit DC power converted into frequency for 20-40 kHz high frequency alternating current,
so rapid changes in the current through the coil, rapid changes in the magnetic field,
when the magnetic field in the magnetic lines of force by metal containers (such as iron) at the bottom,
the metal will produce countless small eddy current, we know, current through a conductor have heating effect.
For example, resistance furnace and old-fashioned incandescent lamp is the application of this principle
and the heat emitting light.
Similarly, at the bottom of the pan because of the myriad of eddy current, it will also generate heat effect,
this is how the electromagnetic oven heat the pan.
Inside of the electromagnetic oven, a spiral coil, the coil, resulting in a changing magnetic field,
when changing the magnetic flux through the wok bottom. At the bottom of the iron produced a myriad of eddy current, ultimately, electric energy is changed into heat energy, as shown on the red electric wires.
The coils windings inside the induction heater
Know the electromagnetic oven heating principle, we can understand why when the induction cooker is ON,
If we put on our hand upon it, hands can not be scalded, because, your hand is not metal,
even if there is a changing magnetic field, your hand should never generate eddy current.
If you want, you can do the following interesting experiments.
The two halves of the egg, pan is heated, and the other half, even close to the electromagnetic oven,
also will not be heated, because eggs is not a conductor.
It is same result when put on the Chocolates
As photo showed water is boiled because it is in the pan, the ice is not heated.
If putting newspaper in the middle of the pan and the electromagnetic oven , no eddy current generated in the newspaper,
and of course, is above the iron which in turn heats up.
After we understand the working principle of the electromagnetic oven,
you will find, electromagnetic oven only radiation is 20-40 kHz high frequency alternating current generated
by electromagnetic wave, 20-40 kHz electromagnetic wave, sound seems very high frequency of appearance, but actually not. It is in a "very low" and "low frequency" electromagnetic wave between, than we usually used to listen to the radio radio frequency also much lower.
Therefore, if you ask the electromagnetic furnace has no radiation?
The answer is yes, the radiation of electromagnetic waves, it will cause cancer? This, you have to judge for yourself.
Contact:Emily
Email: emily@motor-machinery.com
Skype: motor.machinery
Mobile: +86-18067425780
Website: http://www.motor-machinery.com; http://www.coilswinding.com
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Pearl
Emily