User ManualTable of Contents2620A/2625A Users Manual1LIMITED WARRANTY & LIMITATION OF LIABILITY2Table of Contents3List of Tables7List of Figures9Safety10Caution10Interference Information10Declaration of the Manufacturer or Importer10Bescheinigung des Herstellers/Importeurs10Safety Terms in this Manual11Symbols Marked on Equipment11AC Power Source12DC Power Source12Use the Proper Fuse12Grounding the Instrument12Use the Proper Power Cord12Do Not Operate in Explosive Atmospheres12Do Not Remove Cover12Do Not Attempt to Operate if Protection may be Impaired12Getting Started13Introduction13The Basics13Turning On the Instrument13Setting Up a Channel13Selecting the Scan Data Destination14Taking Measurements15Viewing Minimum, Maximum, and Last Data Values161. Introduction19The Hydra Series II Data Acquisition Unit21The Hydra Series II Data Logger21Options and Accessories21Applications Software21IEEE-488 Interface Assembly21Connector Set (2620A-100)21Accessories23Where to go From Here232. Overview25Introduction27Setting Up the Instrument27Unpacking and Inspecting the Instrument27Adjusting the Handle27Line Power28Front/Rear Panel Features28Input Channels33Operating Modes33Turning the Instrument On33Front Panel Display34Reading the Display34Left Display34Right Display34Specific Annunciators34Front Panel Buttons35Selecting a Channel35Using the Buttons35Setting up a Channel36Setting Alarm Limits and Mx+B Scaling Values38Alarm Limits38Mx+B Scaling39Setting the Scan Interval39Using the Monitor Function40Using the Scan Function40Reviewing Channel Data40Viewing the Totalizer Count41Using External DC Power41Using the Rack Mount Kit423. Operating the Instrument from the Front Panel43Introduction45Operating Modes45Other Displayed Data46What is the Present Configuration?46If Power is Interrupted46If the Configuration is Reset46Channel Configuration46Selecting Channel, Function, and Range46Setting Alarms51Alarm Limits51Alarm Indications52Resetting Alarm Conditions53Using the Digital I/O Lines53Mx+B Scaling54Instrument Configuration56Entering and Changing Numeric Values56Selecting Scan Interval57Selecting the Measurement Rate57Triggering58External Triggering58Changing the Temperature Unit58Setting Date and Time of Day59Measurement Connections59DC Volts, AC Volts, Frequency, and Thermocouples60Resistance and RTD62Totalizing64General64Connections64Review Array64List Button Functions65Autoprint67Memory Storage67Front Panel Lock out Conditions68Front Panel Review Only Function68Front Panel Monitor Only Function68Computer Interface-Initiated Lockouts69REM Annunciator69Calibration694. Using the Computer Interface71Introduction73Front Panel and Computer Interface Operations73Types of Computer Interface73Using the RS-232 Computer Interface73Setting Communication Parameters (RS-232)74Autoprint and Memory Storage (RS-232)75Autoprint: Computer Interface Control75Autoprint: Output Format75Memory Storage: Computer Interface Control76Memory Retrieval76Memory Full Operation77Clearing Memory77Cabling the Instrument to a Host or Printer (RS-232)77Installation Test78RS-232 Information78Character Echoing78Character Deletion78Device Clear Using Ctrl C78RS-232 Prompts79Sample Program Using the RS-232 Computer Interface79Using the IEEE-488 Interface79IEEE-488 Operating Limitations79Installing the IEEE-488 Interface79Enabling the IEEE-488 Interface82Installation Test83General Information (RS-232 and IEEE-488)83How the Instrument Processes Input83Input Strings84Input Terminators84Typical Input Strings84Sending Numeric Values to the Instrument (RS-232 and IEEE-488)86Sending Input Strings to the Instrument86How the Instrument Processes Output86Service Requests (IEEE-488 only) and Status Registers87Event Status and Event Status Enable Registers89Status Byte Register89Reading the Status Byte Register90Service Request Enable Register91Instrument Event Register91Computer Interface Command Set925. Additional Considerations117Introduction119Measurement Rate119Advanced Trigger Mechanisms119Front Panel Trigger Control119Computer Interface Trigger Control119Both External and Monitor Alarms Disabled (Type 0)120External Trigger Enabled (Type 1)120Monitor Alarm Enabled (Type 2)122Thermal Voltages122When Measuring Resistance or Temperature (RTD)122True RMS Measurements124Effects of Internal Noise in AC Measurements124Waveform Comparison (True RMS vs Average Responding)124Making Mixed Measurements125Using Shielded Wiring127General Rule127Alternate Suggestions127Non-Isolated Sensor Configuration127Isolated and Shielded Sensor Configuration127In More Detail1286. Maintenance129Introduction131Cleaning131Line Fuse131Self-Test Diagnostics and Error Codes131Performance Tests132Accuracy Verification Test135Channel Integrity Test135Thermocouple Measurement Range Accuracy Test1374-Terminal Resistance Test138Thermocouple Temperature Accuracy Test139Open Thermocouple Response Test141RTD Temperature Accuracy Test142RTD Temperature Accuracy Test (Using Decade Resistance Source)142RTD Temperature Accuracy Test (Using DIN/IEC 751)143Digital Input/Output Verification Tests143Digital Output Test144Digital Input Test144Totalizer Test145Totalizer Sensitivity Test146Dedicated Alarm Output Test147External Trigger Input Test149Calibration149Variations in the Display150Service150Appendices151A. Specifications153Introduction153Accuracies at Ambient Temperatures Other Than Specified153Response Times153DC Voltage Inputs154Input Impedance154Normal Mode Rejection154Common Mode Rejection154Maximum Input154Cross-Talk Rejection154Thermocouple Inputs155Input Impedance157Common Mode and Normal Mode Rejection157Cross-Talk Rejection157Open Thermocouple Detect157RTD Inputs157Type1572-Wire Accuracy158Maximum Current Through Sensor158Typical Full Scale Voltage158Maximum Open Circuit Voltage158Maximum Sensor Temperature158Cross-talk Rejection158AC Voltage Inputs158Ohms Inputs161Frequency Inputs162Typical Scanning Rate163Maximum Autoranging Time164Totalizing Input164Digital Inputs164Trigger Input165Digital and Alarm Outputs166Real-Time Clock and Calendar166Environmental166General1672625A Data Storage1682620A Options168B. ASCII & IEEE-488 Bus Codes169Introduction171C. IEEE-488.2 Devise Documentation Requirements171Introduction171Implementation of IEEE Standard 488.2-1987171D. Making Mixed Measurements177Introduction177Signal Cross Talk in a DC Voltage Channel177AC Signal Cross Talk Into an AC Voltage Channel178AC Signal Cross Talk Into an Ohms Channel178AC Signal Cross Talk Into a Frequency Channel178AC Signal Crosstalk Into a Temperature Channel179E. Binary Upload of Logged Data (LOG_BIN?) (2625A only)181Introduction181Decoding the ASCII String181Floating Point Conversion183Example184F. RS-232 Cabling187Introduction187Connections187Cables187Hydra Configuration Record195Index196Size: 900 KBPages: 197Language: EnglishOpen manual
