Search results
Results from the WOW.Com Content Network
Since PIR sensors have ranges of up to 10 meters (30 feet), a single detector placed near the entrance is typically all that is necessary for rooms with only a single entrance. PIR-based security systems are also viable in outdoor security and motion-sensitive lighting; one advantage is their low power draw, which allows them to be solar-powered.
The generalised chemical structure of polyisocyanurate showing the isocyanurate group. The polyols are abbreviated as R-groups.. Polyisocyanurate (/ ˌ p ɒ l ɪ ˌ aɪ s oʊ s aɪ ˈ æ nj ʊər eɪ t /), also referred to as PIR, polyol, or ISO, is a thermoset plastic [1] typically produced as a foam and used as rigid thermal insulation.
A typical water meter register showing a meter reading of 8.3 gallons. Notice the black "1" on the odometer has not yet fully turned over, so only the red hand is read. Water meters connected to remote reading devices through three-wire cables. There are several types of registers on water meters.
The National Water Quality Inventory Report to Congress is a general report on water quality, providing overall information about the number of miles of streams and rivers and their aggregate condition. [65] The CWA requires states to adopt standards for each of the possible designated uses that they assign to their waters.
Occupancy sensor types include: PIR sensors, which work on heat difference detection, measuring infrared radiation.Inside the device is a pyroelectric sensor which can detect the sudden presence of objects (such as humans) who radiate a temperature different from the temperature of the background, such as the room temperature of a wall.
A water detector is an electronic device that is designed to detect the presence of water for purposes such as to provide an alert in time to allow the prevention of water leakage. A common design is a small cable or device that lies flat on a floor and relies on the electrical conductivity of water to decrease the resistance across two contacts.
They are used for quality assurance, process control, and for research and development in many industries. Jacques and Pierre Curie discovered the piezoelectric effect in 1880, [ 3 ] but only in the 1950s did manufacturers begin to use the piezoelectric effect in industrial sensing applications.
Air bubbler systems contain no moving parts, making them suitable for measuring the level of sewage, drainage water, sewage sludge, night soil, or water with large quantities of suspended solids. The only part of the sensor that contacts the liquid is a bubble tube which is chemically compatible with the material whose level is to be measured.