How Does an Electric-Range Element Work?

Introduction

Electric energy comes to homes via electric wires from local power plants and once in the home, the electricity enters an electric-range's element. At the flick of a switch, the electricity is converted to heat. This is due to the resistive nature of the element. The resistance translates to heat, which in turn heats the pots and cooks the food through heat conduction and convection. The electric-range element works on the following electrical principles of resistivity, conductivity and reflection.

Resistivity

Voltage can be equated to the pressure that is needed to push electrons through a conductor; therefore resistance is equivalent to the friction that arises as the electron attempt to pass through the wire. The resistance of a material depends on its length, the area of its cross-section and its resistivity. Resistivity (rho) depends on what material the wire is made of. The wire used in an element is designed to resist and not completely block the flow of electricity. The amount of resistivity is related to the amount of electricity that is converted to heat. The wire should be also stable at the required temperatures of the element, resist oxidation at high temperatures and be non corrosive. The most commonly used resistant wire in the element is nichrome, an alloy of nickel and chromium.

Conductivity

The nichrome wire is placed within a ceramic binder and placed in a metal sheath or shell. This kind of element is called metal-sheathed or a calrod elements. This commonly used element has a fast heat-up time and quick response. The heat is conducted through the binder to the sheath, which is the coil that you see. The heat is further conducted to heat your pot. It is important to note that the sheath does not conduct electricity, only heat; you will not be electrocuted by touching the element. The heat heats up the pot via conduction, which in turn heats the contents of the pot via convection.

Reflector

This reflector is found below the coil. The element sends heat in all directions, making it inefficient; therefore a metal reflector is installed below the element. The reflective surface redirects the heat upwards to where it is needed. It also acts as a reservoir for spills in keeping your stove top clean.

Working Together

The switch, which acts like a dimmer, is connected to the element; it determines the amount of electricity that flows through the element. The higher the electric current that is allowed to pass through the element, the higher the internal resistance of the wire which leads to a hotter element.

Warnings

Do not immerse your element in water; this will compromise its function. It is recommended that you hire a certified technician to repair your stove.