Pdf calibration of a platinum resistance thermometer pt100. Standard platinum resistance thermometer sprt isotech 670. All the platinum resistance thermometers use handmade coilwound platinum sensing elements to give high accuracy and low drift. A platinum resistance thermometer prt is a thermometer constructed from a high purity platinum element wirewound coil or thin film placed in a tube of metal or glass and sealed with an inert atmosphere andor mineral insulator. Find out information about platinum resistance thermometer. The four wire resistance thermometer configuration even further increases the accuracy and reliability of the resistance being measured. Industrial platinum resistance thermometer sensors from sai global. Fluke calibration secondary standard prts fill the gap between affordable, but temperaturelimited secondary reference prts and more expensive, highly accurate sprts. This reading output is converted to temperature via a calibration equation. Standard specification for industrial platinum resistance. Abstract afterabriefresumeofsomephasesofplatinumresistancethermometryadescrip.
Platinum resistance thermometer pprt calibration laboratory provides calibrations based on the international temperature scale of 1990 its90 1 to government owned facilities, industry and secondary calibration laboratories. The restriction of the upper limit of the use of a platinum resistance thermometer to the silver freezing point is caused by the lack of information on the standard characteristic of the platinum. En 60751iec 60751 platinum resisance t empert ature detecorst rtd. Platinum resistance thermometer thermocouple thermistor sensor platinumwire wound or flat film resistor thermoelement, two dissimilar metalsalloys ceramic metal oxides accuracy typical values 0. The company started as a manufacturer of scales and weights.
The pprt calibrates standard platinum resistance thermometers sprts by realizing the fixedpoints covering the range 83. Operating limits and tolerances of platinum resistance thermometers per en 60751. Semistandard platinum resistance thermometers isotech. A comprehensive handbook and tutorial will help you get the very best performance and stability from your 670 platinum resistance thermometer. In order to promote public education and public safety, equal justice for all, a better informed citizenry, the rule of law, world trade and world peace, this legal document is hereby made available on a noncommercial basis, as it is the right of all humans to. Fr series elements are designed for applications where high vibration resistance as well as high temperature stability is vital. After completion, repeat the process for the additional uuts. Isotechs ukasaccredited lab can calibrate to the smallest of uncertainties. Am19601950 standard platinum resistance thermometer users. The traditional sensing element of a resistance thermometer consists of a coil of small diameter wire wound to a precise resistance value. R t resistance at temperature t ohm r 0 resistance at temperature 0 o c ohm t temperature o c a 3. The 56265628 probes provide a calibrated accuracy of 0. The relative change in resistance temperature coefficient.
The simplest resistance thermometer configuration uses two wires. A working form of resistance thermometer sensor is defined in iec and din specifications and this forms the basis of most industrial and laboratory electrical thermometers. Platinum resistance thermometer definition of platinum. Thermometer construction what factors affect a platinum thermometers resistance. The platinum sensing resistor, pt100 to iec 751 is dominant in europe. Common rtd sensing elements constructed of platinum. The basis of the international practical temperature scale of 1968 from 259. It is only used when high accuracy is not required as the resistance of the connecting wires is always included with that of the sensor leading to errors in the signal. For equipment that does not allow characterization, tolerance testing may be your only choice and this is a common situation in industry today. The linearization equation for the pt100 thermometer is. Resistance thermometers are slowly replacing thermocouples in many lower temperature industrial applications below 600c.
In preparation for the its90 many national laboratories designed platinum resistance thermometers that would work to the gold point of 1064c. Platinum resistance thermometer calibration procedures are similar whether the method selected is characterization or tolerance testing. Common rtd sensing elements constructed of platinum, copper or nickel have a repeatable resistance versus temperature relationship r vs t and operating temperature range. Evaluation of uncertainties of the temperature measurement by standard platinum resistance thermometer calibrated at the defining fixed points according to its90 is a problem that can be solved in different ways. Wirewound glass resistor mgl specification wirewound platinum glass resistor mgl construction model i platinum wire wound around a glass spindle. The platinum resistance thermometer andthe platinum 10 percent rhodium versus platinum thermocouple are the specified interpolating instruments of. Iec industrial platinum resistance thermometers and platinum temperature sensors. Features hold button to freeze display and capture reading.
This monograph describes the calibration of standard platinum resistance thermometers at the nbs including the equipment, techniques, and procedures. Platinum resistance thermometers prts are calibrated at the highest level in fixed points, as specified in the international temperature scale of 1990 its90. Calibration should be specified to suit the particular operating range and application. Order online the fluke calibration a probe,secondary prt,ohm 14 x12 from transcat.
Am19601950 standard platinum resistance thermometer users guide. Platinum resistance thermometer calibrations nist page. Troemner was founded over 160 years ago by henry troemner. The r vs t relationship is defined as the amount of resistance change of the sensor per degree of temperature change. Operating limits and tolerances of platinum resistance. Uncertainty in sprt resistance at the triple point of water. How to calibrate an rtd or platinum resistance thermometer. Fisherbrand traceable rtd platinum thermometer rtd.
The resistance tends to be almost linear with temperature. The platinum resistance thermometer johnson matthey. Recent modifications in the construction of platinum. Guide to the realization of the its90 platinum resistance thermometry 3 56 5. Platinum resistance thermometer thermocouple thermistor sensor platinumwire wound or flatfilm resistor thermoelement, two dissimilar metalsalloys ceramic metal oxides accuracy typical values 0. The fluke platinum resistance thermometer prt, is designed to be a secondary standard interpolating instrument converting temperature to resistance. These thermometers operate on the principle that electrical resistance changes in pure metal elements, relative to temperature.
Platinum sensing resistors are available with alternative ro values, for example 10, 25 and 100 ohms. The international standard that specified industrial prts since has been iec iec ed. Platinum resistance thermometer information peak sensors. Platinum resistance thermometry at high temperatures. This document outlines the recurrent concepts and technologies that apply to all resistance thermometers produced by wika. Resistance thermometers come in a number of construction forms and offer greater stability, accuracy and repeatability. Fluke calibration secondary standard prts fill the gap between affordable, but temperature limited secondary reference prts and more expensive, highly accurate sprts. Resistance thermometers may be called rtds resistance temperature detectors, prts platinum resistance thermometers, or sprts standard platinum resistance thermometers. Instruction manual series 162 standard platinum resistance thermometers models 162ce, 162cg, 162d, 162k isotech north america 158 brentwood drive, unit 4 colchester, vt 05446 phone. It is used both for precision measurements of the highest accuracy and for routine industrial work. The paper presents a procedure based on the propagation of distributions using the monte carlo method. Platinum resistance thermometry at high temperatures nist page. The 670 platinum resistance thermometer can be supplied with r tpw and w ga only, or with full nist traceable or ukas accredited calibration. Typical industrial applications include analytical equipment, chemical plants and mechanical equipment.
Thermometers failed to perform to the expected stabilities and so the its90 reduced the upper temperature of contact thermometry to the silver point 961. In top diagram a standard two terminal rtd is used with another pair of wires to form an additional loop that cancels out the lead resistance. Pdf a common problem found in the industrial metrology is the reliability of the results obtained from temperature instruments, especially. Platinum resistance thermometers prt characteristics. What is the principle of working platinum resistance. A platinum resistance thermometer prt was selected for this application.
Application of monte carlo method for evaluation of. Platinum 100ohm fourwire rtd probe can be used in liquids, airgas, and semisolids. The market was surveyed for a prt probe that would meet these accuracy and. Platinum resistance thermometry unt digital library. Platinum resistance thermometer synonyms, platinum resistance thermometer pronunciation, platinum resistance thermometer translation, english dictionary definition of platinum resistance thermometer.
Platinum resistance thermometer article about platinum. Small tolerances on diameter allow problem free installation in protective tubes. The platinum resistance thermometer is a versatile instrument for temperature measurement in. The pprt laboratory utilizes a computer and software to automate and speed the collection of. A platinum resistance thermometer has resistances of 200. The resistance of the platinum wire is measured via passing an electrical current ac or dc through it, and measuring the voltage with a suitable device. The platinum resistance thermometer prt is very widely used below 500 c as a thermometric sensor. For best accuracy with modern equipment choose characterization.
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