Level measurement devices can detect, indicate, and/or help control liquid or solid levels. Level measurement devices can be separated into two categories: direct, or mechanical, measurement and electronic measurement.
Solar cells are multiple panel-conductor-electrode systems which, when joined with several others, can generate a tangible and significant amount of electrical current.
Furnaces and kilns are very similar in design and are closely related to dryers. The major difference is that dryers only have an outer metal shell, whereas furnaces and kilns have refractory bricks for insulation.
Condensers make use of a condensing medium, such as air or water, that absorbs heat from a vapor. As the vapor loses its heat to the condensing medium, its temperature falls to the saturation point, and it condenses to a liquid.