Main Classification
Electric heaters refer to appliances that use electrical energy to achieve heating effects. According to the type of heating method, they can be roughly divided into three categories:
1. Electromagnetic heating
Electromagnetic heating generates an alternating magnetic field through electronic circuit board components. When a ferrous container is placed on it, the container surface cuts the alternating magnetic field lines, producing an alternating current (i.e., eddy current) in the metal part at the bottom of the container. The eddy current causes the iron atoms at the bottom to move rapidly and irregularly, colliding and rubbing against each other to generate heat energy, thereby achieving the effect of heating the object. Since the iron container itself generates heat, the thermal conversion rate is particularly high, up to 95%. Induction cookers and induction stoves all use electromagnetic heating technology.
2. Infrared heating
The heat transfer form of infrared is radiation heat transfer, which transmits energy through electromagnetic waves. When far-infrared rays irradiate the heated object, part of the rays are reflected back, and part penetrate through. When the wavelength of the emitted far-infrared matches the absorption wavelength of the heated object, the object absorbs the far-infrared, causing the molecules and atoms inside the object to "resonate" — generating intense vibration and rotation, which increases the temperature of the object, achieving the purpose of heating.
3. Resistance heating
A heating method that uses electric current passing through an electric heating element to release heat to heat the workpiece. Common resistance wire heating, ceramic heaters, resistance coil heating, and quartz tube heating are all based on resistance heating in principle.
