Resistanssilämmitin

Resistanssilämmitin, known in English as a resistance heater or resistive heater, is a device that converts electrical energy into thermal energy through the process of Joule heating. This occurs when an electric current passes through a resistive material, causing it to heat up. The amount of heat generated is proportional to the square of the current and the resistance of the material, as described by the formula P = I^2R, where P is power, I is current, and R is resistance.

These heaters are widely used in various applications due to their simplicity, reliability, and relatively low cost. Common examples include electric stoves, toasters, hair dryers, electric kettles, and industrial heating processes such as furnaces and ovens. They can also be found in water heaters, space heaters, and defroster elements in vehicles. The resistive element is typically made from materials with high electrical resistance and a high melting point, such as nichrome (an alloy of nickel and chromium), tungsten, or molybdenum, often formed into wires, ribbons, or rods.

The design of a resistanssilämmitin can vary significantly depending on its intended use. Some are simple exposed coils, while others are embedded within insulating materials or enclosed in protective casings to enhance safety and efficiency. The control of temperature is usually achieved by regulating the electrical current or voltage supplied to the heating element, often through thermostats or variable power controls.