Temperature sensors remote

Improved sensors allow computer monitoring of the system for safety and protection of the equipment from damage. Sensors include lubrication-flow monitors and alarms, bearing-temperature sensors, belt scales, rotation sensors, and proximity sensors to detect ore level under the crusher. The latter prevent jamming of the output with too high an ore level, and protect the conveyor from impact of lumps with too low an ore level. Motion detectors assure that the conveyor is moving. Control applied to crusher systems including conveyors can facilitate use of mobile crushers in quarries and mines, since these can be controlled remotely by computer with reduced labor. 

A particularly difficult problem in microwave processing is the correct measurement of the reaction temperature during the irradiation phase. Classical temperature sensors (thermometers, thermocouples) will fail since they will couple with the electromagnetic field. Temperature measurement can be achieved either by means of an immersed temperature probe (fiber-optic or gas-balloon thermometer) or on the outer surface of the reaction vessels by means of a remote IR sensor. Due to the volumetric character of microwave heating, the surface temperature of the reaction vessel will not always reflect the actual temperature inside the vessel [7]. 

Sampling sites are also referred to as station locations. For water column work, depth profiles are constructed from seawater samples collected at representative depths. Temperature and salinity are measured in situ with sensors. Remote-closing sampling bottles deployed from a hydrowire are used to collect water for later chemical analysis, either on the ship or in a land-based laboratory. The standard chemical measurements made on the water samples include nutrients (nitrate, phosphate, and silicate), dissolved O2, and total dissolved inorganic carbon (TDIC) concentrations. 

It is also possible to use an implanted temperature sensor to monitor temperature remotely and without using this type of invasive measurement. For example, microchip transponders (ELAMS, BioMedic Data Systems, Inc., Seaford DE, USA) have been shown to reliably monitor temperature without significant difference from rectal temperature measurements (35). 

Some applications require that sensing be performed in a location that precludes the presence of RF electronic circuitry. For example, the location may be subjected to extreme temperatures or pressures, or it may simply not be large enough to allow room for the circuitry. In all of these situations, mounting of the sensor remote from the RF electronics is necessary. 

Finally, we wish to note that hydrogen is not the only small molecule, where molecular exchange symmetry causes the existence of a para- and an ortho- spin isotopomer. Water is another important example. In the gas phase it exists as para- or ortho-water. They are distinguishable by IR. Their concentration ratio is used in astronomy as a remote temperature sensor. The spin conversion mechanisms of these isotopomers are still an open field for future studies [98, 99]. 

Filling. Compost is brought into the room. If remote reading temperature sensors are... 

Radiation thermometers sore used for remote (non-contact) sensing of temperature in situations where the contact sensors cannot be used. Operation is based on the principles of heat transfer through thermal radiation. Radiation thermometers focus the infrared energy from a heat source onto a black body (target) within the radiation thermometer enclosure (Fig. 18.23). One of the contact temperature sensors described previously is incorporated into the target to measure the target temperature. 

The thermographic sensor is used as a remote sensing radiometer when a reference target is imaged. It is usually necessary to correct for emissivity and atmospheric transmission to determine surface temperature with a reasonable degree of accuracy. 

Process-variable feedback for the controller is achieved by one of two methods. The process variable can (I) be measured and transmitted to the controller by using a separate measurement transmitter with a 0.2-I.0-bar (3-15-psi pneumatic output, or (2) be sensed directly by the controller, which contains the measurement sensor within its enclosure. Controllers with integral sensing elements are available that sense pressure, differential pressure, temperature, and level. Some controller designs have the set point adjustment knob in the controller, making set point adjustment a local and manual operation. Other types receive a set point from a remotely located pneumatic source, such as a manual air set regulator or another controller, to achieve set point adjustment. There are versions of the pneumatic controller that support the useful one-, two-, and three-mode combinations of proportional, integral, and derivative actions. Other options include auto/manual transfer stations, antireset windup circuitry, on/off control, and process-variable and set point indicators. 

Temperature control Immersed fiber-optic probe (max. 300 °C) Outside IR remote sensor (optional)... 

Cavity size (volume) Approx. 50 L Delivered power 1500 W Max. output power 1200 W Temperature control Outside IR remote sensor Immersed fiber-optic probe (optional) Pressure measurement Pneumatic pressure sensor (optional) Cooling system Air flow through cavity 100 m3 h1 External PC Optional not required as integrated key panel is standard equipment ... 

Temperature measurement is achieved by means of a remote IR sensor beneath the lower outer surface of the vessels. The operation limit of the IR sensor is 400 °C, but it is regulated by the software safety features to 280 °C as the operation limits of the materials used are around 300 °C. For additional control, temperature measurement in a reference vessel by means of an immersed gas-balloon thermometer is available. The operational limit of this temperature probe is 310 °C, making it suitable for reactions under extreme temperature and pressure conditions. 

Capability of remote measurements. The small size of the fiber and its electrical, chemical, and thermal inertness allow long-term location of the sensor deep inside complex equipment and thereby provide access to difficult locations where temperature may be of interest. Beyond this, however, certain of the optical techniques allow noncontact or remote sensing of temperature. 

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