Accuracy of the thermocouple measurements | Escort 3016B, 3008B

17 Appendix

17.2.Accuracy of the thermocouple measurements

The measurement inaccuracies thereafter are given as maximum values: typical values are 2 to 3 times less.

The measurement accuracy in temperature is the sum of several possible sources of inaccuracy: Pl: accuracy of standardisation

Ps: cold weld accuracy

Pm: accuracy of the measurement of the equivalent voltage

Pd: accuracy of the measurement offsets

The total accuracy is then: Pt = Pl + Ps + Pm + Pd

For the recorder:

Pl = 0.25 C for all the thermocouples

Ps = 1.25 C for all the thermocouples

Pd = 0.15 % of the offset

Pm = given in the tables

Measurement accuracy: Pm

The measurement accuracy Pm depends on the voltage range used by the appliance. The measurement error in degrees will then be the measurement error in voltage divided by the slope in V/C of the thermocouple. For each thermocouple, an illustrative value of the slope is given at a given temperature. This slope value is relevant for the thermocouple and allows you to calculate the temperature error. If you want to have even further accuracy, you have to read the slope in the thermocouple reference tables (because it changes with the temperature).

EXAMPLE OF ACCURACY CALCULATION

A measurement is made with the range 50C centred on 25C with a J thermocouple without cold weld compensation.

Pt = Pl + Ps + Pm + Pd

Pl = 0.25 C (accuracy of standardisation)

Ps = 0C (no cold weld compensation)

Pd = 0.04C (+ 0.15 % of the temperature, paper medium)

Pm = 0.20C (extracted from the table at range 50C)

Max. total accuracy:

Pt = 0.25 + 0.04 +0.20 = 0.49C

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Escort 3016B, 3008B, 3004B user manual Accuracy of the thermocouple measurements, Example of Accuracy Calculation

Contents

Recorders Page Page Page Garanty Page Contents Diagrams Inputs / Outputs Appendix Page Important informations Symbols and definitionsImportant Information Security instructions Conformity and restrictions of the appliance Symbols that appear in this manualSymbols that appear on the appliance See chapter Technical specifications Presentation Presentation Presentation Escort 3016B and Escort 3004B Rear side or top side Description of the screen Front side Keys Thumb Wheel F1 Modify Updating the Internal Software Initialisation Initialisation and Precautions of USE Fuse Initialisation Storage precautions of the records Initialisation Power up of Escort 3008B Initialisation Power up of Escort 3016B and Escort 3004B Configuration on POWER-UP Measure of temperature with a thermocouple Measure of temperature with a PT100Measure of voltage Connection of the grounding Measure of intensity Menu key Calibration Offset Routine maintenanceCalibration of the offsets Unplug the appliance before any intervention Menu key Reload Factory Coeff Factory adjustement Initialisation and precautions of use Use Mode key Help key Set up key Use Escort 3008B recorder only Chart key Analogical channels Channels set up key Use Use Logic channels Channel on/off key Display Ft oscilloscope mode Display keyVertical or horizontal sweep on screen Use Digital display Direction keysUse Display XY  Y channel Trigger key  Blocks and Files Replay key Start/Stop key Paper-feed key Diagrams Diagrams Positions of the channels Change diagrams Single / Several thresholds TriggersTriggers Trigger key, parameters Start and Stop Single threshold Triggering with analogical channels Triggers Several thresholds Triggers Trigger according to thresholds Triggers Trigger according to the slope Triggering with logical channels Mathematical Calculations DefinitionsMathematical calculations Types of calculations High MinimumMaximum Low Width   VCyclical RMS Direct Mode Configuration of the plottingDirect mode Direct mode Triggering plotting Direct mode Rearmament of the plotting Writing dataExample of plotting program  Channels set up key Memory Mode Configuration Triggering of the acquisitionMemory mode Sampling period Manual with the F2 key Urge triggeringTrigger Triggering position Internal memory, blocks Recording Double Trigger mode Memory mode Memory mode Memory output Memory mode 10. GO/NOGO Mode Configuration and triggering of the acquisition10 Go/Nogo mode Creation of the frame Memory Mode 10 Go/Nogo mode Channels for Go/Nogo selected in the Trigger Use of the frame File Mode Configuration and start of the acquisitionFile mode Limits Binary fileAscii file File mode File Management GeneralFile management Management of the configuration files Saving the configuration files Saving the acquisitions File management Loading the configuration filesManagement of the acquisition files Press the Load from disk key Real time File management Loading the acquisition files PC Software for Analysis File management File transfer with FTP File management Display with Escortview File management ESCORTview Myfile.rec /x Printing Plot set up and launchReplay , key Setup Plot Printing with Escort 3016B and Escort 3004B Printing Printer Setup Printing Pin no Input or Ouput Supplementary input / output connectorInputs / Outputs Inputs / Outputs External clock Logical inputs13.1.1.Use Plotting and display 13.1.2.Use Alarm outputsPower supply output Keyboard input Not used. Reserved to future applications Mouse inputXGA screen output 14.8. RS232 Ethernet RJ45 interface USB Interface Ethernet Interface Interface EthernetEthernet interface Programming language Format of the reception messagesSyntax of a reception message Data Syntax of a message unit Ethernet interface Format of the emission messages Text data Standard instructions Structure of the status data Indication of the status of the appliance Status register Registers of service request Registers of standard events Validation register Register of the alarms Example Using the structure of status data Programming dictionary Setup CHAnnel Ethernet interface Parameters of the channels Changing mode Functions of the channels and between the channelsCurrent function Header Parameters Examples Directplot Ethernet interface Chart Starttrig Triggerings Header Parameters Examples Triglog P1 Ethernet interface Triggers MEMSpeed Reloadings, real-time savings RECord Ethernet interface Launching plotting and recording Replay memory output Ethernet interface Direct display Ethernet interface Service request Error messages Ethernet interface Isolated inputs Technical Specifications Technical specifications Temperature recording SamplingBandwidth Type of measurements Multiplexed inputs Calibre Supplementary inputs / outputs Display Alarm outputsExternal power supply Paper Environmental conditions Escort 3008B File acquisitionCommunication interface Miscellaneous Environmental conditions Escort 3016B & Escort 3004B Technical specifications Dimensions, weight Accordance test Electromagnetic compatibility Internal saving battery 16.13.3 Expandable items Accessory items16.13.2 Optional accessory items Items furnished with the appliance Voltage-type inputs AppendixInformation about the ranges of the inputs Appendix Thermocouple K type input Appendix Thermocouple J type input Thermocouple S type input Appendix Thermocouple T type input Thermocouple E type input Appendix Thermocouple B type input Thermocouple W5 type input Appendix Thermocouple N type input Example of Accuracy Calculation Accuracy of the thermocouple measurements Temperature C Accuracy of the PT100 measurementsSlope V/ C Accuracy class index of class