Temperature Calibrators - TEMPSENS - #2

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W TEMPSENS INSTRUMENTS TOTAL SOLUTION FOR TEMPERATURE CALIBRATION What is Calibration ? Calibration is the comparing of a measurement device (an unknown) against an equal or better standard. A standard in a measurement is considered the référence; which is the one taken to be the more correct of the two in the comparison. One calibrâtes to find out how far the unknown is from the standard. Accurate Température Calibration Température Calibration has many facets. It can be carried out thermally in the case of probes or electrically in the case of Instrument and it can be performed directly with certifiée! equipment, or indirectly with traceable standards. Thermal (Température) calibration is achieved by elevating (or depressing) the température sensor to a known, controlled température and measuring the corresponding change in its associated electrical parameter (voltage or résistance). The accurately measured parameters compared with that of a certified référence probe; the absolute différence represents the calibration error. If the sensor is connected to a measuring instrument, the sensor and the instrument combination can be effectively calibrated bythis technique. A typical gênerai purpose System comprises of a thermal référence (stable température source), a certified référence probe with its certificate, a précision electronic digital thermometer, bridge or digital voltmeter. Température Source Dry BlockCalibrator Provides the most convenient, portable facilities for checking industrial probes and they usually reasonable rapid heating and cooling. The unit consists of a spécial designed heating block within which is located internai holes for the probes. Although the block température is accurately controlled, any indication provided should be used for guidance only. As with any comparison technique a certified sensor and indicator should be used to measure the block température and used as a référence for the test probe. Two types of unit are available; portable units which can be taken on to plant for the on-site calibration and laboratory units to which industrial sensors are brought as required. Stirred Liquid Bath Provide superior thermal environment for probe immersion as no air gap exist between the probe and the médium. Thermal coupling is therefore much better than the alternatives described, and the stirring results in very even heat distribution throughout the médium. Alcohols are used for température below 0 Deg C, water from 0 to 80 Deg C and oil for up to300DegC Black Body Source Blackbodies are référence sources used for testing infrared Systems. They are required in industry for calibration of pyrometers, infrared line scanners or caméras. In laboratory, they are part of benches for characterization of complex optronic Systems. Tempsens offers a wide range of blackbodies to coverall Customers' needs Cold Junction Compensation By Connecting any thermocouple to measurement device three dissimilar métal junction are created in the circuit: the » thermocouple junction itself, or hot junction, and the junction between * each lead and the measurement device, or cold junctions. Thèse cold junction provide their own thermoelectric voltages that are proportional to the température at the device terminais. Atechnology known as cold junction compensation is therefore used to remove this unwanted effect