Nernst Lamp

Nernst Lamp (Nernst), a type of incandescent electric lamp. In it, a refractory rod is used as the glowing element, the main mass of which consists of magnesium oxide. This rod can be heated to 2,000°, at which it emits bright light. In the Nernst lamp, preliminary heating of the rod is required, since in a cold state it does not conduct electricity. This is usually achieved by means of a special spiral surrounding the rod and also heated by current. When the rod glows, it begins to conduct electricity, and further heating is maintained by the current passing through it, while the heating spiral is usually turned off automatically with the help of an electromagnetic relay located in the upper part of the lamp. Energy consumption in the Nernst lamp is about 1.3 watts per candle and its efficiency is about 1.4%. In composition, the light of the Nernst lamp is very close to the light of gas incandescent burners with an Auer cap. The N. lamp was invented in 1897 by the German physicochemist Nernst. At present, N. lamps have gone out of use due to their fragility and low efficiency, and are used only in laboratory research to obtain a linear light source, but even there they are being replaced by special single-filament incandescent lamps.