Dionex DX-120 User manual

DX-120 ION CHROMATOGRAPH
OPERATOR’S MANUAL
© 1998 Dionex Corporation
Document No. 031183
Revision 03
September 1998

©1998 by Dionex Corporation
All rights reserved worldwide.
Printed in the United States of America.
This publication is protected by federal copyright law. No part of this publication
may be copied or distributed, transmitted, transcribed, stored in a retrieval system,
or transmitted into any human or computer language, in any form or by any means,
electronic, mechanical, magnetic, manual, or otherwise, or disclosed to third parties
without the express written permission of Dionex Corporation, 1228 Titan Way,
Sunnyvale, California 94088-3603 U.S.A.
DISCLAIMER OF WARRANTY AND LIMITED WARRANTY
THIS PUBLICATION IS PROVIDED “AS IS” WITHOUT WARRANTY OF
ANY KIND. DIONEX CORPORATION DOES NOT WARRANT,
GUARANTEE, OR MAKE ANY EXPRESS OR IMPLIED
REPRESENTATIONS REGARDING THE USE, OR THE RESULTS OF THE
USE, OF THIS PUBLICATION IN TERMS OF CORRECTNESS,
ACCURACY, RELIABILITY, CURRENTNESS, OR OTHERWISE.
FURTHER, DIONEX CORPORATION RESERVES THE RIGHT TO REVISE
THIS PUBLICATION AND TO MAKE CHANGES FROM TIME TO TIME
IN THE CONTENT HEREINOF WITHOUT OBLIGATION OF DIONEX
CORPORATION TO NOTIFY ANY PERSON OR ORGANIZATION OF
SUCH REVISION OR CHANGES.
EMISSIONS COMPLIANCE
This equipment meets ITE standard EN 55022 part A for radiated emissions and is
suitable for use in a laboratory environment. Operation of this equipment in a
residential area, however, may cause interference to radio and television reception.
TRADEMARKS
Teflon® and Tefzel® are registered trademarks of E.I. duPont de Nemours & Co.
AutoSuppression, DX-LAN, IonSep®, MPIC®, OmniPac®, OnGuard,
Self-Regenerating Suppressor, and SRSare trademarks of Dionex Corp.
PRINTING HISTORY
Revision 01, May 1996
Revision 02, March 1997
Revision 03, September 1998

Contents
1• Introduction
1.1 About This Manual . . . . . . . . . . . . . . . . . 1-2
1.1.1 Typefaces and Conventions . . . . . . . . 1-3
1.1.2 Safety Messages and Notes . . . . . . . . 1-4
1.1.3 Symbols . . . . . . . . . . . . . . . . . . . 1-5
1.2 Related Manuals . . . . . . . . . . . . . . . . . . . 1-5
2 •Description
2.1 Operating Features . . . . . . . . . . . . . . . . . 2-1
2.1.1 Front Control Panel . . . . . . . . . . . . 2-3
2.1.2 Pump . . . . . . . . . . . . . . . . . . . . 2-6
2.1.3 Configuration DIP Switches . . . . . . . 2-6
2.1.4 Eluent Reservoirs . . . . . . . . . . . . . 2-7
2.1.5 Component Panel . . . . . . . . . . . . . 2-8
2.1.6 Rheodyne Injection Valve . . . . . . . . . 2-11
2.1.7 Detector Cells . . . . . . . . . . . . . . . 2-12
2.1.8 DS4 Detection Stabilizer . . . . . . . . . 2-13
2.2 Dual-Column Configuration Features . . . . . . . 2-15
2.2.1 Column Select Mode . . . . . . . . . . . 2-16
2.2.2 Eluent Select Mode . . . . . . . . . . . . 2-18
2.3 Fluid Schematics . . . . . . . . . . . . . . . . . . 2-19
2.4 Control Modes . . . . . . . . . . . . . . . . . . . . 2-22
2.4.1 Local Mode . . . . . . . . . . . . . . . . . 2-22
2.4.2 Remote Mode . . . . . . . . . . . . . . . 2-22
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2.5 TTL Control . . . . . . . . . . . . . . . . . . . . . 2-23
2.5.1 Injection Valve/Remote Start Control . . 2-23
2.5.2 Recorder Range Control . . . . . . . . . . 2-23
3 •Operation and Maintenance
3.1 Preparing Eluents . . . . . . . . . . . . . . . . . . 3-1
3.1.1 Degassing Eluents . . . . . . . . . . . . . 3-1
3.1.2 Filtering Eluents . . . . . . . . . . . . . . 3-2
3.1.3 Pressurizing Eluent Reservoirs . . . . . . 3-2
3.2 Preparing Samples . . . . . . . . . . . . . . . . . 3-3
3.2.1 Collecting and Storing . . . . . . . . . . . 3-3
3.2.2 Pretreating . . . . . . . . . . . . . . . . . 3-3
3.2.3 Diluting . . . . . . . . . . . . . . . . . . . 3-4
3.3 Operating . . . . . . . . . . . . . . . . . . . . . . 3-5
3.3.1 Starting Up . . . . . . . . . . . . . . . . . 3-5
3.3.2 Injecting the Sample . . . . . . . . . . . . 3-7
3.4 Using an Integrator . . . . . . . . . . . . . . . . . 3-9
3.5 Running under PeakNet Control . . . . . . . . . . 3-9
3.6 Optimizing Temperature Compensation . . . . . . 3-10
3.6.1 With a DS4 . . . . . . . . . . . . . . . . . 3-10
3.6.2 With a CDM-3 Cell . . . . . . . . . . . . 3-10
3.7 Maintenance . . . . . . . . . . . . . . . . . . . . . 3-11
4 •Troubleshooting
4.1 Alarms . . . . . . . . . . . . . . . . . . . . . . . . 4-1
4.2 Error Codes . . . . . . . . . . . . . . . . . . . . . 4-3
4.3 Liquid Leaks . . . . . . . . . . . . . . . . . . . . . 4-4
4.4 Pump Difficult to Prime . . . . . . . . . . . . . . 4-8
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4.5 Pump Loses Prime . . . . . . . . . . . . . . . . . 4-8
4.6 Pump Does Not Start . . . . . . . . . . . . . . . . 4-9
4.7 No Flow . . . . . . . . . . . . . . . . . . . . . . . 4-9
4.8 Excessive System Backpressure . . . . . . . . . . 4-9
4.9 Peak “Ghosting” . . . . . . . . . . . . . . . . . . . 4-10
4.10 Nonreproducible Peak Height or Retention
Time . . . . . . . . . . . . . . . . . . . . . . . . . 4-11
4.11 Abnormal Retention Time or Selectivity . . . . . 4-11
4.12 DS4 Temperature Inaccurate . . . . . . . . . . . . 4-12
4.13 No Detector Response . . . . . . . . . . . . . . . 4-13
4.14 Low Detector Output . . . . . . . . . . . . . . . . 4-14
4.15 High Detector Output . . . . . . . . . . . . . . . . 4-14
4.16 Noisy or Drifting Baseline . . . . . . . . . . . . . 4-15
5 •Service
5.1 Replacing Tubing and Fittings . . . . . . . . . . . 5-2
5.2 Changing the Sample Loop . . . . . . . . . . . . 5-2
5.3 Isolating a Restriction in the Liquid Plumbing . . 5-3
5.4 Replacing the DS4 Cell . . . . . . . . . . . . . . . 5-3
5.5 Cleaning Cell Electrodes . . . . . . . . . . . . . . 5-5
5.6 Calibrating the Cell Constant . . . . . . . . . . . 5-6
5.7 Calibrating the Pump Flow Rate . . . . . . . . . . 5-8
5.8 Cleaning and Replacing Pump Check Valves . . . 5-8
5.9 Replacing a Pump Piston Seal . . . . . . . . . . . 5-9
5.10 Replacing a Pump Piston . . . . . . . . . . . . . . 5-12
5.11 Replacing the Pressure Transducer Waste
Valve O-Ring . . . . . . . . . . . . . . . . . . . . 5-14
5.12 Changing the Main Power Fuses . . . . . . . . . . 5-15
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A •Specifications
A.1 Electrical . . . . . . . . . . . . . . . . . . . . . . . A-1
A.2 Environmental/Physical . . . . . . . . . . . . . . . A-1
A.3 Control Panel . . . . . . . . . . . . . . . . . . . . A-2
A.4 Pump . . . . . . . . . . . . . . . . . . . . . . . . . A-2
A.5 Pulse Damper . . . . . . . . . . . . . . . . . . . . A-2
A.6 Detector . . . . . . . . . . . . . . . . . . . . . . . A-2
A.7 Conductivity Cell . . . . . . . . . . . . . . . . . . A-3
A.8 DS4 Detection Stabilizer (Optional) . . . . . . . . A-3
A.9 Valves . . . . . . . . . . . . . . . . . . . . . . . . A-3
A.10 Delay Volume . . . . . . . . . . . . . . . . . . . . A-4
B •Installation
B.1 Facility Requirements . . . . . . . . . . . . . . . . B-1
B.2 Installation Overview . . . . . . . . . . . . . . . B-1
B.3 Rear Panel Connections . . . . . . . . . . . . . . B-2
B.3.1 Power Connection . . . . . . . . . . . . . B-2
B.3.2 Switched AC Outlet Connection
(Optional) . . . . . . . . . . . . . . . . . . B-4
B.3.3 Waste Lines . . . . . . . . . . . . . . . . . B-5
B.3.4 Gas Connection . . . . . . . . . . . . . . B-5
B.3.5 DX-LAN Cable Connection (Optional) . B-6
B.4 Eluent Reservoir Connections . . . . . . . . . . . B-8
B.5 Pump Setup . . . . . . . . . . . . . . . . . . . . . B-8
B.5.1 Priming the Pump . . . . . . . . . . . . . B-8
B.5.2 Checking the Pump Flow Rate
Calibration . . . . . . . . . . . . . . . . . B-9
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B.6 Connections to Chromatography Components . . B-10
B.6.1 Backpressure Requirements . . . . . . . . B-12
B.6.2 Self-Regenerating Suppressor (SRS)
Installation . . . . . . . . . . . . . . . . . B-13
B.6.3 Column Installation . . . . . . . . . . . . B-17
B.7 TTL Control Connections (Overview) . . . . . . . B-19
B.7.1 TTL Inputs . . . . . . . . . . . . . . . . . B-19
B.7.2 TTL Outputs . . . . . . . . . . . . . . . . B-20
B.7.3 Ferrite Core Installation on TTL Output
Cables . . . . . . . . . . . . . . . . . . . . B-21
B.8 Autosampler Connections (Optional) . . . . . . . B-22
B.8.1 Autosampler Outlet Line Connection . . B-22
B.8.2 AS40 Automated Sampler Connections . B-22
B.8.3 AS3500 Automated Sampler
Connections . . . . . . . . . . . . . . . . B-24
B.9 Recorder and Integrator Connections
(Optional) . . . . . . . . . . . . . . . . . . . . . . B-27
B.9.1 Chart Recorder Connections . . . . . . . B-27
B.9.2 4400 or 4600 Integrator Connections . . B-27
B.10 Configuration DIP Switch Settings . . . . . . . . B-29
B.11 DS4 Detection Stabilizer Installation . . . . . . . B-33
B.12 CDM-3 Cell Installation . . . . . . . . . . . . . . B-35
B.13 Injection Valve Connections . . . . . . . . . . . . B-36
B.14 Column Switching Valve Connections . . . . . . . B-37
B.15 DX-LAN Card Installation (Optional) . . . . . . . B-38
C •Integrator Programming
C.1 Integrator Power-up Configuration . . . . . . . . C-1
C.2 Setting Offsets . . . . . . . . . . . . . . . . . . . . C-2
C.3 Area Percent Mode . . . . . . . . . . . . . . . . . C-2
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C.4 Using DIALOG to Create a Method . . . . . . . . C-3
C.4.1 Time Functions . . . . . . . . . . . . . . . C-3
C.4.2 Creating a Method . . . . . . . . . . . . . C-4
C.5 BASIC Programming . . . . . . . . . . . . . . . . C-7
D •Conductivity Detection
D.1 How Conductivity Is Measured . . . . . . . . . . D-1
D.2 Conductivity of Solutions . . . . . . . . . . . . . D-2
D.2.1 Effect of Hydration Sphere and
Solvent on Conductivity . . . . . . . . . . D-4
D.2.2 Effect of Temperature on Conductivity . D-4
D.2.3 Species Detected by Conductivity . . . . D-5
D.2.4 Chemical Suppression . . . . . . . . . . . D-6
D.2.5 Eluents for Conductivity Detection . . . D-9
E •Glossary
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1• Introduction
The Dionex DX-120 Ion Chromatograph performs isocratic ion
analysis applications using conductivity detection. The DX-120 is an
integrated system, which includes a pump, detector, and injection
valve. The chromatography components, including the column(s),
Self-Regenerating Suppressor(SRS), and conductivity cell are
ordered separately. These components are mounted on the inside of
the DX-120 door.
The DX-120 can be controlled locally, using the front panel keypad
and display, or remotely, from a PeakNet workstation. The PeakNet
workstation consists of a computer with a Dionex DX-LAN
interface card and PeakNet software (Release 4.30 or higher)
installed. Limited remote control is also available using TTL signals.
The DX-120 can be ordered as a single-column system or a
dual-column system. The dual-column system allows switching
between two sets of columns (column select mode) or between two
eluents (eluent select mode). In the eluent select mode, the DX-120
can perform step gradients.
The following models are available:
Configuration Voltage/Line Frequency* Without
DX-LAN With DX-LAN
Single-column 115 VAC/60 Hz P/N 050100 P/N 050200
100 VAC/50 Hz P/N 050103 P/N 050203
230 VAC/50 Hz P/N 050106 P/N 050206
Dual-column 115 VAC/60 Hz P/N 050102 P/N 050202
100 VAC/50 Hz P/N 050105 P/N 050205
230 VAC/50 Hz P/N 050108 P/N 050208
*Must match the voltage and line frequency of the installation site’s
power source.
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1.1 About This Manual
Chapter 1
Introduction Introduces the DX-120 and explains the
conventions used in the manual, including
safety-related information.
Chapter 2
Description Describes the DX-120 operating features, the
chromatographic fluid path, and the control
modes.
Chapter 3
Operation and
Maintenance
Provides operating and routine preventive
maintenance procedures.
Chapter 4
Troubleshooting Lists problems, with step-by-step procedures to
isolate and eliminate their sources.
Chapter 5
Service Provides step-by-step instructions for routine
service and parts replacement procedures.
Appendix A
Specifications Lists the DX-120 specifications and installation
site requirements.
Appendix B
Installation Describes how to install the DX-120.
Appendix C
Integrator
Programming
Describes how to program a Dionex 4400 or
4600 integrator for automated control of the
DX-120.
Appendix D
Conductivity
Detection
Describes conductivity detection and its
applications.
Appendix E
Glossary Defines terms commonly used in ion
chromatography.
DX-120 Operator’s Manual
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1.1.1 Typefaces and Conventions
•Capitalized bold type indicates a front panel button. For
example:
Press Pump to turn on the pump.
•Upper-case bold type indicates information displayed on
the front panel screen. For example:
LEAK ALARM displays when a leak occurs.
•Upper-case italic type indicates a grouping of front panel
buttons. For example:
Use the buttons in the DISPLAY group to select the type
of information shown on-screen.
•When a function can be controlled by a DIP switch
setting, the switch and position numbers are in
parentheses. For example:
(SW1-3) indicates DIP switch 1, position 3.
(SW2-5, 6, 7, 8) indicates DIP switch 2, positions 5, 6, 7,
and 8.
1
•
Introduction
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1.1.2 Safety Messages and Notes
The DX-120 meets European, EMC, and safety requirements
per Council Directives 73/23/EEC and 89/336/EEC, EN
61010-1:1993 (safety), EN 50082-1:1992 (susceptibility), and
EN 55011:1991 (emissions). The TUV/CE and GS safety
label on the DX-120 attests to compliance with these
standards.
The DX-120 is designed for ion chromatography applications
and should not be used for any other purpose. If there is a
question regarding appropriate usage, contact Dionex before
proceeding.
This manual contains warnings and precautionary statements
that, when properly followed, can prevent personal injury
and/or damage to the instrument. Safety messages appear in
bold type and are accompanied by icons, as follows:
Indicates an imminently hazardous situation which, if not
avoided, will result in death or serious injury.
Indicates a potentially hazardous situation which, if not
avoided, could result in death or serious injury.
Indicates a potentially hazardous situation which, if not
avoided, may result in minor or moderate injury.
Indicates that the function or process of the instrument
may be impaired. Operation does not constitute a hazard.
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Informational messages also appear throughout this manual.
These are labeled NOTE and are in bold type:
NOTE
NOTES call attention to certain information. They alert
you to an unexpected result of an action, suggest how to
optimize instrument performance, etc.
1.1.3 Symbols
The symbols below appear on the DX-120, or on DX-120
labels.
Alternating current
Protective conductor terminal
Power supply is on
Power supply is off
1.2 Related Manuals
During installation and operation of the DX-120, you may need to
refer to one or more of the following manuals for information about
other components or instruments in the system.
•4440 Integrator User’s Guide (Document No. 034200) or 4600
Integrator User’s Guide (Document No. 034408)
•AS40 Automated Sampler Operator’s Manual (Document
No. 034970)
•Installation of Dionex Ferrule Fittings (Document No. 034213)
~
1
•
Introduction
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•PeakNet Software User’s Guide (Document No. 034914)
•Installing the PeakNet System (Document No. 034941)
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2 •Description
2.1 Operating Features
Figures 2-1 and 2-2 illustrate the main operating features of the
DX-120.
Figure 2-1. DX-120 Operating Features (Exterior)
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Figure 2-2. DX-120 Operating Features (Interior)
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2.1.1 Front Control Panel
The control panel liquid crystal display (LCD) shows status
information and alarm conditions. Press a button in the group
labeled DISPLAY to determine the type of status information
shown. The remaining buttons control DX-120 operation.
Button Function
DISPLAY
Displays the pump flow rate setting (0.5 to 4.5 mL/min).
Displays the pump pressure transducer reading (0 to
27.6 MPa or 0 to 4000 psi)
NOTE
MPa is the default pressure unit. For psi, set DIP
SW1-4 on. See Section B.10 for details.
Displays the total conductivity reading (0 to 999.9 µS).
Displays the offset conductivity reading (-999.9 to
999.9 µS). Offset conductivity is the total conductivity
minus the offset for the current run (see the description of
the Auto Offset button).
Figure 2-3. DX-120 Control Panel
Table 2-1. Control Panel Button Functions
2
•
Description
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Button Function
RECORDER
Delivers a chart mark signal to the analog output. The mark
is 10% of the full-scale voltage.
Delivers a 100% signal to the analog output. Pressing the
button continuously keeps the output signal at full scale. The
default full-scale voltage is 1 V, but can be changed to 10 V
(SW4-4).
Reduces the analog output signal to zero. Pressing the
button continuously keeps the output signal at zero.
COMPONENT ON/OFF
Turns the gas pressure to the eluent reservoirs on and off.
When on, the LED on the button is illuminated. This button
is disabled when the DX-120 is in Remote mode (see
Local/Remote below).
Turns the pump flow on and off. When on, the LED on the
button is illuminated. This button functions in Local or
Remote mode.
Turns the SRS power on and off, as well as the DS4
Detection Stabilizer, if installed. When on, the LED on the
button is illuminated. In the dual-column configuration, this
button controls the power to the SRS and DS4 of the
selected column set (see Section 2.2.1). This button is
disabled when the DX-120 is in Remote mode (see
Local/Remote below).
SYSTEM CONTROL
Toggles between Local and Remote control modes. Local is
control from the DX-120 control panel and Remote is
control from a PeakNet workstation via the DX-LAN. The
selected mode is shown in the lower right-hand corner of the
display.
A red LED on the left side of the button indicates an alarm
condition. The top line of the display indicates the source of
the alarm: cabinet or cell leak, high or low pressure, or SRS.
Pressing the button clears the alarm. If the alarm condition
is still present, the alarm reappears after 15 seconds.
Table 2-1. Control Panel Button Functions (continued)
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Button Function
Offsets the background conductivity. After start-up, allow
the system to equilibrate. The display shows the background
conductivity (the eluent conductivity before sample
injection). Press Auto Offset to offset this background
reading and zero the chromatogram baseline.
Switches the injection valve between the Load and Inject
positions. The current position is shown in the lower
left-hand corner of the display.
When switched from Load to Inject, the DX-120 also:
- sends a chart mark signal to the analog output (SW4-7)
- performs an auto offset (SW3-3)
- sends a TTL signal indicating that an injection has
occurred
After 1 minute, the valve automatically returns to the Load
position (SW1-1).
This button is disabled when the DX-120 is in Remote
mode.
COLUMN SELECTION
The COLUMN SELECTION buttons are active in the
dual-column configuration only.
In column select mode, this button initiates the column
switching sequence from column set B to column set A (see
Section 2.2.1). In eluent select mode, this button switches to
eluent delivery from line A (see Section 2.2.2).
In column select mode, this button initiates the column
switching sequence from column set A to column set B (see
Section 2.2.1). In eluent select mode, this button switches to
eluent delivery from line B (see Section 2.2.2).
These buttons are disabled when the DX-120 is in Remote
mode.
Table 2-1. Control Panel Button Functions (continued)
2
•
Description
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2.1.2 Pump
The pump is located on the right side of the main
compartment (see Figure 2-2). The knob on the front of the
pump adjusts the flow rate from 0.5 to 4.5 mL/min.
Eluent Save Mode
If the DX-120 is idle (i.e., no control panel buttons have been
pressed and no PeakNet commands have been received) for
90 minutes, the pump flow automatically decreases to 1/20th
of its current flow rate and the SRS cycles on and off. When
this occurs, the LEDs on the Pump and SRS buttons flash.
Press any button to return to the last selected flow rate.
To turn off this feature, reset the Pump Time-out DIP switch
(SW1-2).
2.1.3 Configuration DIP Switches
The DIP switches on the left side of the main compartment
control system parameters. The factory-set defaults can be
changed to meet specific system and application requirements
(see Section B.10).
NOTE
In this manual, when a function is controlled by a DIP
switch setting, the switch and position numbers are shown
in parentheses. For example: (SW1-3, 4) indicates DIP
switch 1, positions 3 and 4.
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