2635A
 Limited Warranty & Limitation of Liability
 Table of Contents
 Front Panel Operations
2635A
 Memory Card Operations
 Printer Operations
 Index
 2635A
 List of Tables
 Viii
 List of Figures
 Overall PC-to-Instrument Modem Connection
 Interference Information
 Symbols Marked on Equipment
Safety Terms in this Manual
 DC Power Source
AC Power Source
Use the Proper Power Cord
Use the Proper Fuse
 Introduction
Ten Minute Tour
 SET Func
Power Func
OFF VAC
Ten Minute Tour
 Selecting a Measurement Scale. Select
 Scan MON
Scan
 Review
SET
 Mx+B SET Mx+B
Alrm
SLO
 YEAR TotAL
 OFF
 DESt
LISt
Mode
ALL
 Xxiii
 Xxiv
 Preparation for Use
 2635A
 Preparation for Use 1 Introduction
 Hydra
 Operating Modes
Introduction
 Data Bucket Features
 Alarm Outputs Connector Digital I/O Connector RS-232C
Ground Terminal AC Power Connector Universal Input Module
Front Panel Operation
Memory Card Operation
 Printer Operation
Computer Operation
Modem Operation
 Applications Software
Measurement Capabilities
 Connector Set, 2620A-100
Options and Accessories
Hydra Starter Package
Hydra Logger
 Options and Accessories
Setting Up the Instrument
Unpacking and Inspecting the Instrument
Model
 Connecting the Instrument to a Power Source
Adjusting the Handle
 DC Operation
AC Operation
Input Channels
 Measurement Connections
Using Shielded Wiring
Crosstalk
Universal Input Module Connections
 Measurement Connections
 Wire 4T Connection Source
Wire 2T Connection Source
Sense
Resistance
 DC Power
Alarm Outputs Connections
Alarm Outputs
External Trigger Input
 Digital I/O
Digital I/O Connections
Totalizer Input
Digital I/O
 Front Panel Indicators
Controls and Indicators
Front Panel Controls
Auto MON
 12. Annunciator Display
11. Secondary Display
 Key
Rate K J Clock K I Mode K P
Front Panel Keys Description
 Clear Local K Comm K L Zero Single K Q
Func Alarm
Annunciator Descriptions
MON Scan SET
 OFF Auto Limit HI, LO Review MIN, MAX Last PRN EXT REM CAL
Annunciator Annunciator Descriptions
 2635A
 Front Panel Operations
 Using the Monitor Mode Using the Review Mode
 Front Panel Operations
 Hydra Data Bucket
 Summary of Front Panel Operations
How to use the Control/Annunciator Diagrams
 Turning the Power on
Configuring the Instrument for Operation
 Default Setting
Configuration Reset Default Settings Parameter
Selftest Error Codes Description
Code
 Selecting a Channel
Configuring a Measurement Channel
Restrictions
 Func SET Func
Configuring a Channel to Measure DC Volts
 Configuring a Channel to Measure AC Volts
Configuring a Channel to Measure AC Volts
 Configuring a Channel to Measure Resistance
Configuring a Channel to Measure Resistance
 Configuring a Channel to Measure Frequency
Configuring a Channel to Measure Frequency
 Resistance-Temperature Detectors
Configuring a Channel to Measure Temperature
Resistance Temperature Detectors Restrictions
Thermocouples
 Positive Lead Color
Thermocouple Ranges Type Material
ANSI* IEC
Negative Lead Material
 Configuring a Channel to Measure Temperature RTDs
 Configuring a Channel Off
Setting Operating Conditions
 11. Setting the Scan Interval
Setting the Scan Interval
 Setting the Alarms
Setting the Measurement Rate
Alarm Indications While Scanning
RAtE
 Alarm Indications While Reviewing
Alarm Indications While Monitoring
Clearing Alarm Parameters from a Channel
 Alarms and Monitor-Alarm Triggering
Alarms and Autoprinting
Alarms and Mx+B Scaling
TLL Alarm Outputs Channels 0 to Decimal
 Channels
TTL Alarm Outputs Channels 4 to
 Alrm Limit
13. Setting the Alarms
 Examples
Setting the Mx+B Scaling
Clearing Mx+B Scaling from a Channel
 14. Setting the Mx+B Scaling
 Required From the previous
 Using the Scan Mode
 Path to OPEn DAtxx Menu
Memory Card Data Extraction
 16. Memory Card Error Messages
Memory Card Error Messages
 17. Using the Monitor Mode
Using the Monitor Mode
 18. Using the Review Mode
Using the Review Mode
 Monitor-Alarm Trigger
Additional Features
Scan Triggering Options
External Trigger
 19. Scan Triggering Options
Totalizer Operation
 Xxxxx
Digital Input/output Lines
 Year
Setting Date and Time
Mn.dY
 Reading Instrument Software Versions
Returning to the Local Mode
Returning to the Local Mode. Press
 Instrument Interfaces
REM Monitor Mode Review
Front Panel Key Lockout Options
Memory Card Interface
 Using the RS-232 Computer Interface With a Modem
Using the RS-232 Computer Interface With a Printer
RS-232 Computer Interface
 2635A
 Recording Measurement Results During Scanning
Memory Card Operations
 256KB
 WRITE-PROTECT Switch
Insertion Direction PIN Connector
Lithium Battery 3 Volts
Summary of Memory Card Operations
 Data Files
Setup Files
Memory Card Capacity
 Inserting and Removing the Memory Card
Installing or Replacing the Memory Card Battery
 Memory Card Error Codes Probable Cause
Error
 Files
Initializing a Memory Card
Init
SUrE
 MOdE
Recording Measurement Results During Scanning
 Using Setup Store
Setup File Procedures
SEtUP
StorE
 Using Setup Load to Load Configuration Files
Using Setup Load
 ErASE
Using Setup Erase
 Using Data Open
Data File Procedures
DAtA
 Using Data Erase to Delete a Measurement Data File
Using Data Erase
 NnnnK
Setup and Data Files Directory
 USEd
Setup and Data File Current Status
 Memory Card File Operations to and from a PC
 Computer Operations
 Op82f.eps
 Summary of Computer Operations
Connecting the Instrument to a PC
 PC Connection With DB-9
Connector
PC Connection With DB-25
 PAR
Configuring the Instrument for Computer Operations
 Testing the Instrument/PC RS-232 Interface
Configuring the PC for Computer Operations
 Rstfunc 0,VDC,4PRINTTYPE 0,0PRINT 1*TRG
 2635A
 Open COM1,9600,N,8,1,CS,CD for Random AS #1
Testing the RS-232 Interface Using Gwbasic
 Print #1, Printtype 0,0PRINT INPUT$20, #1
Testing the RS-232 Interface Using Qbasic
 IDN?
 How the Instrument Processes Input
Computer Interface Commands and Operation
Input Terminators
 Sending Numeric Values to the Instrument
Input String Examples
How the Instrument Processes Output
 Instrument Event Register IER
Status Registers
 Overview of Status and Event Data Registers
 Bit Name
Standard Event Status Register ESR
Instrument Event Register IER Description
 Bit Event Status Register ESR Name Description
Status Byte Register STB
 Xmodem File Transfers
Computer Interface Command Set
IEB
MAV ESB
 Echo
Command and Query Summary
DIOLEVELS? Dolevel
Func FUNC? RTDR0 RTDR0? RANGE?
 MAX? MIN? NEXT?
Rate RATE?
MON MONCHAN? MONVAL?
Scalemb SCALEMB?
 Lock LOCK? Locs Lwls Rems Rwls
Tempconfig TEMPCONFIG?
Format FORMAT?
Reviewclr
 Date Time TIMEDATE?
IDN? TST?
Total TOTAL? Totaldbnc TOTALDBNC?
Trigger TRIGGER?
 Cntlc CLS ESE ESE? ESR?
Command and Query Reference
 Field Description
IDN?
OPC OPC? RST SRE SRE?
 TST? WAI
TRG
 ALARMS?
 Alarmassoc
 Alarmassocclr
ALARMASSOC?
 ALARMDOLEVELS?
Alarmdolevel
 ALARMLIMIT? CLS Date
Alarmlimit
LO OFF
 DIR
DIOLEVELS? Digital I/O State Query
 Echo ESE ESE? ESR? FILEERROR? Fileload
 FILEOPEN? Fileremove
 FILESPACE? Filestore
 Configuration File Tag
 Measurement Units String
Format
MX+B
VDC
 Range Voltage Ohms Frequency
Func
 IEE? IER?
FUNC? IDN? IEE
 Intvl INTVL? LAST?
 Lock
 LOCK? Locs LOG? LOGGED?
 Logmode LOGMODE? Lwls
LOGBIN? Logclr LOGCLR1 LOGCOUNT?
 MAX? MCARD?
BIT Memory Card Battery Status
MAX?
 MCARDSIZE?
Mcardformat
 Disables monitoring
 OPC OPC? Print
 PRINT? Printtype
 PRINTTYPE?
 Rate RATE? Rems Reviewclr RST RTDR0
 RTDR0? Rwls
 Scalemb
 SCALEMB? Scan
 SCAN? SCANTIME? SRE SRE? STB? Tempconfig
 Total
TEMPCONFIG?
 TOTAL? Totaldbnc TOTALDBNC? TRG Trigger
 Returns an integer representing the present trigger type
 Sample Program Gwbasic 1
 Sample Program Gwbasic 2
 Sample Program Qbasic 1
 Sample Program QBASIC2
 Sample Program Qbasic 3
 Sample Program QuickC 1of
 Sample Program QuickC 2
 Sample Program QuickC 3
 Sample Program QuickC4
 Sample Program QuickC5
 Printer Operations
 Op83f.eps
 Summary of Printer Operations
Connecting the Instrument to a Printer
 Printer
SERIAL-INPUT
PARALLEL-INPUT
 Configuring the RS-232 Ports for Print Operations
Configuring for Printer Operations
 Printing Measurement Data and Memory Card Directory
Problems?
Printing Measurement Results During Scanning
 Printing Measurement Data and Memory Card Directory
 Printing the Review Array
Printing the Review Array
 Printing the Memory Card Directory
Printing the Directory of the Memory Card
 2635A
 Modem Operations
Configuring the Instrument for Modem Operations
 Op84f.eps
 Overall PC-to-Instrument Modem Connection
Summary of Modem Operations
 Configuring the Instrument Modem for Modem Operations
Connecting the Modem to a PC for Modem Configuration
 Modem Connection With PC DB-25 Connector
Modem Connection With PC DB-9 Connector
 Connecting the Modem to an Instrument
Connecting the Modem to an Instrument
 Enter
Configuring the Instrument for Modem Operations
 Testing the RS-232/Modem Interface
 Dedicated Alarm Output Test
Maintenance
 Calibrator
 Line Fuse
Introduction Cleaning
 Error Power-Up Error Codes Description
Selftest Diagnostics and Error Codes
Performance Tests
 Performance Tests
 Instrument Type
Recommended Test Equipment Minimum Specification
Recommended Model
Instrument Type Recommended Model
 Function
Accuracy Verification Test
Range
Input Level Frequency
 Channel Integrity Test
 Thermocouple Measurement Range Accuracy Test
 Four-Terminal Resistance Test
Thermocouple Temperature Accuracy Test
 Open Thermocouple Response Test
 5700A
Hydra Input Module
UUT
 RTD Temperature Accuracy Test Using Decade Resistance Source
RTD Temperature Accuracy Test
 Temperature Simulated
RTD Temperature Accuracy Test Using DIN/IEC 751 RTD
Temperature Accuracy
Decade Resistance Source
 Digital Output Test
Digital Input/Output Verification Tests
 Digital Input Test
Dolevel 0,0 CR
 Terminal Grounded
Totalizer Test
Digital Input Values
State of Digital Inputs
 Totalizer Sensitivity Test
Dedicated Alarm Output Test
 Maintenance
 GND Source Input
Alarm Output
Module Sense
Hydra
 External Trigger Input Test
Calibration
 Variations in the Display
Service
 Appendix Title
Appendices
Page
 Accuracies at Ambient Temperatures Other than Specified
Specifications
Resolution
DC Voltage Measurements
 Common Mode Rejection
Normal Mode Rejection
Accuracy
Input Impedance
 Maximum Input
Appendices
Cross-Talk Rejection
 Accuracy
Resolution
 Type Temperature Days Year Slow Fast 0C to 60C
Temperature Measurements Thermocouples
 2635A
 Common Mode and Normal Mode Rejection
Temperature Measurements RTDs
Open Thermocouple Detect
RTD
 Temperature Slow Fast
Wire Accuracy
AC Voltage Measurements
RTD Type
 Resolution Slow Fast
Table A-10. AC Voltage Measurements Resolution Range
Minimum Input for Rated Accuracy
 DC Component Error
Crest Factor Error
2635A Maximum Voltage Input VS. Frequency Input
Maximum Crest Factor
 Resistance Measurements
 Resolution and Accuracy
2635A Wire Accuracy
Frequency Measurements
Input Sensitivity
 Table A-17. Typical Scanning Rate
Typical Scanning Rate
 Totalizing Input
Maximum Autoranging Time
Digital Inputs
 Input Voltages
Trigger Inputs
Minimum Pulse Width Maximum Frequency Specified Conditions
Maximum Latency
 Environmental Specifications
Digital and Alarm Outputs
Real-Time Clock and Calendar
 General
 Power
Weight
2635A Voltage Ratings
Size
 Crosstalk Considerations
AC Signal Cross Talk in a DC Voltage Channel
 AC Signal Cross Talk into an Ohms Channel
AC Signal Cross Talk into an AC Voltage Channel
 AC Signal Crosstalk into a Temperature Channel
AC Signal Cross Talk into a Frequency Channel
 2635A
 Decoding the Ascii String
Binary Upload of Logged Data
 +--------+--------+--------+--------+
 Figure C-1. Ascii String Decoding
 Floating Point Conversion
 Mmsb
Sign Bit
Mlsb Lmsb
 Figure C-2. FloatingPoint Conversion
 Example
 Figure C-3. Example
 Cables
RS-232 Cabling
 Figure D-1. Summary of RS-232 Connections
 RS-232 Cabling D
 Figure D-3. Hydra DB-9 to PC DB-25 RS-232 Connection
 RS41 Cable or Equal
 Printer
 Side Male Female
Connector
Side
 2635A
 Bit Binary-Coded-Decimal Table
 Binary
Table E-1 -Bit Binary-Coded-Decimal
 Memory Card File Formats
Setup File Format
Data File Format
 Trigger
 Memory Card File Formats
 Unsigned char mdr unsigned char bdr float rtdr0
 Appendices
 2635A
 Appendices
 2635A
 Effect of Internal Noise in AC Measurements
True RMS Measurements
Waveform Comparison True RMS VS Average Responding
 Waveform RMS CAL Hydra Only
Component
Sine
PK-PK
 Scan Rate
Temperature Units
RS-232-C Communication
Output
 Hydra Memory Card Record
 Index
 2635A
 Index
 2635A