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