Agilent Technologies U2802A manual Calibration Information, Zeroing Function

Page 78

5 Calibration

Calibration

Calibration Information

The Agilent U2802A is factory calibrated and the calibration constants are stored in the EEPROM. During initial setup, the calibration constants are read from the EEPROM before any measurements are taken.

Zeroing Function

The Agilent U2802A thermocouple input device operating in thermocouple mode can be set to zero mode, where the differential inputs of each channel are shorted together. This zeroing function is used to measure the total system offset errors due to initial offset error, temperature drift error, and long term drift error from the DAQ (U2355A or U2356A) and the U2802A. This measurement can then be subtracted from subsequent measurements in order to remove the system offset error.

62	Agilent U2802A 31-Channel Thermocouple Input User’s Guide

Image 78

Contents Agilent U2802A 31-Channel Thermocouple Input Device U T I O N WA RN I N G Safety Information U2802A 31-Channel Thermocouple Input User’s Guide Regulatory Markings General Safety Information Do not dispose in domestic household waste Environmental Conditions This Guide November-2007 Regulatory Information for Australia/New Zealand XII Contents Calibration List of Figures List of Tables Getting Started Introduction to Agilent U2802A 31-Channel Thermocouple Input Top View Product OverviewProduct Outlook Front ViewSide View Bottom ViewProduct Dimensions Top View Front ViewStandard Purchase Items Checklist Installations and Configurations Ii. If Agilent IO Libraries Suite 14.2 has Check Your System Requirements Hard disk space 1 GBCheck Your Pre-Installed IO Libraries Suite You do not have the Agilent IO Libraries installed, orIii. If Agilent IO Libraries Suite is not installed Getting Started Install the DAQ Hardware Driver Install the Agilent Measurement ManagerGetting Started Agilent U2802A 31-Channel Thermocouple Input User’s Guide Getting Started Connect Your DAQ Device to the PC Hardware VerificationConnect Your U2802A to DAQ Launch Your Agilent Measurement Manager IVI-COM Drivers Choosing Instrument-Specific InterfaceChoosing Class-Compliant Interface Using Class-Compliant Interface IVI- COMIVI-COM Driver Installation Programming EnvironmentsGetting Started Agilent U2802A 31-Channel Thermocouple Input User’s Guide Getting Started Features and Functions Features Applications System Overview 1System overview of U2802A with DAQTheory of Operation Functionality of the SystemFunctional Block Diagram 3Functional block diagram for U2802A4Functional block diagram for thermocouple mode in U2802A Analog input channel circuitry5Floating signal source configuration in U2802A Agilent U2802A 31-Channel Thermocouple Input User’s Guide Cold junction sensor Digital controlOpen Thermocouple Detection Trigger, Counter, External Timebase, and Analog OutputFeatures and Functions Pin Configurations and Assignments Pin Configurations Pin AssignmentsConnector J71 Pin DescriptionPin Configurations and Assignments Connector J50 Pin Configurations and Assignments Connector J60 Pin Pin name DescriptionConnector Pinout Rear panel pinout for Connector3Connector 2 pin assignment for U2355A and U2356A Pin Configurations and Assignments Product Specifications General Specifications Operating EnvironmentProduct Characteristics General CharacteristicsOther Features System Accuracy Specifications Accuracy on page 54 for calculation methodologyWith different number of averaging points U2356A @ 0 C to 18 C and 28 C to 45 C Calculating System Accuracy Example= 0.02% × 33.102 mV = 6.62 µV = 6.62 µV ÷ 59 µV/C = 0.112 C System accuracy without thermocouple sensor error System accuracy with thermocouple sensor errorThermoelectric Characteristics System Typical PerformanceTypical Error vs. Measurement Performance Making Accurate Temperature Measurements Product Specifications Calibration Calibration Calibration InformationZeroing Function Restore Factory Calibration Calibration Contact us