Waters 432 Conductivity Detector
Operator’s Guide
71500043202/Revision B
Copyright © Waters Corporation 2010 All rights reserved
Copyright notice
© 2010 WATERS CORPORATION. PRINTED IN THE UNITED STATES OF AMERICA AND IN IRELAND. ALL RIGHTS RESERVED. THIS
DOCUMENT OR PARTS THEREOF MAY NOT BE REPRODUCED IN ANY FORM WITHOUT THE WRITTEN PERMISSION OF THE PUBLISHER.
The information in this document is subject to change without notice and should not be construed as a commitment by Waters Corporation. Waters Corporation assumes no responsibility for any errors that may appear in this document. This document is believed to be complete and accurate at the time of publication. In no event shall Waters Corporation be liable for incidental or consequential damages in connection with, or arising from, its use.
Trademarks
Alliance, Millennium, and Waters are registered trademarks of Waters Corporation, and Empower, LAC/E, PowerLine, SAT/IN, Sep-Pak, UltraWISP, WISP and “THE SCIENCE OF WHAT’S POSSIBLE.” are trademarks of Waters Corporation.
Other registered trademarks or trademarks are the sole property of their owners.
Customer comments
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We seriously consider every customer comment we receive. You can reach us at tech_comm@waters.com.
Contacting Waters
Contact Waters® with enhancement requests or technical questions regarding the use, transportation, removal, or disposal of any Waters product. You can reach us via the Internet, telephone, or conventional mail.
Safety considerations
Some reagents and samples used with Waters instruments and devices can pose chemical, biological, and radiological hazards. You must know the potentially hazardous effects of all substances you work with. Always follow Waters contact information
Contacting medium Information
Internet The Waters Web site includes contact information for Waters locations worldwide.
Visit www.waters.com.
Telephone and fax From the USA or Canada, phone 800 252-HPLC, or fax 508 872 1990.
For other locations worldwide, phone and fax numbers appear in the Waters Web site.
Conventional mail Waters Corporation 34 Maple Street Milford, MA 01757 USA
Good Laboratory Practice, and consult your organization’s safety representative for guidance.
Safety advisories
Consult Appendix A for a comprehensive list of warning and caution advisories.
Operating this instrument
When operating this instrument, follow standard quality-control (QC) procedures and the guidelines presented in this section.
Applicable symbols
Audience and purpose
Symbol Definition
Manufacturer location
Authorized representative of the European Community
Confirms that a manufactured product complies with all applicable European Community
directives
Australia C-Tick EMC Compliant
Confirms that a manufactured product complies with all applicable United States and Canadian safety requirements
Consult instructions for use
Intended use of the Waters 432 Conductivity Detector
Use the Waters® 432 Conductivity Detector, as a standalone module or configured as part of an HPLC system, to determine changes in the thermal conductivity of column eluent as compared with that from a reference flow.
The Waters 432 Conductivity Detector is for research use only.
Calibrating
To calibrate LC systems, follow acceptable calibration methods using at least five standards to generate a standard curve. The concentration range for standards should include the entire range of QC samples, typical specimens, and atypical specimens.
When calibrating mass spectrometers, consult the calibration section of the operator’s guide for the instrument you are calibrating. In cases where an overview and maintenance guide, not operator’s guide, accompanies the instrument, consult the instrument’s online Help system for calibration instructions.
Quality-control
Routinely run three QC samples that represent subnormal, normal, and above-normal levels of a compound. Ensure that QC sample results fall within an acceptable range, and evaluate precision from day to day and run to run.
Data collected when QC samples are out of range might not be valid. Do not report these data until you are certain that the instrument performs
satisfactorily.
ISM classification
ISM Classification: ISM Group 1 Class B
This classification has been assigned in accordance with CISPR 11 Industrial Scientific and Medical (ISM) instruments requirements. Group 1 products apply to intentionally generated and/or used conductively coupled
radio-frequency energy that is necessary for the internal functioning of the equipment. Class B products are suitable for use in both commercial and residential locations and can be directly connected to a low voltage, power-supply network.
EC authorized representative
Waters Corporation (Micromass UK Ltd.) Floats Road
Wythenshawe
Manchester M23 9LZ United Kingdom
Telephone: +44-161-946-2400
Fax: +44-161-946-2480
Contact: Quality manager
Copyright notice ... ii
Trademarks ... ii
Customer comments ... iii
Contacting Waters ... iii
Safety considerations ... iii
Safety advisories ... iv
Operating this instrument ... iv
Applicable symbols ... iv
Audience and purpose... iv
Intended use of the Waters 432 Conductivity Detector... v
Calibrating ... v
Quality-control ... v
ISM classification ... v
ISM Classification: ISM Group 1 Class B ... v
EC authorized representative ... vi
1 Introduction ... 1-1
Features ... 1-2 Method of operation ... 1-3 Measurement technique ... 1-3 Flow cell design... 1-3 Ion detection theory ... 1-42 Installing the Detector ... 2-1
Selecting the installation site ... 2-2 Operating environment ... 2-2 Required space ... 2-2 Power requirements... 2-2Table of Contents
Unpacking and inspection ... 2-3 Unpacking ... 2-3 Inspection ... 2-3 AC power connection ... 2-4 Power cord... 2-4 Required material ... 2-6 Procedure... 2-6 I/O signal connections ... 2-7 I/O signal descriptions ... 2-8 PowerLine controller connections ... 2-10 Empower and Millennium32 connections ... 2-13 Data module connections... 2-18 Chart recorder connections ... 2-19 Chart marker input connections... 2-20 Auto Zero input connections... 2-21 Alliance Separations Module connections ... 2-21 Making fluidic connections ... 2-23 Cutting stainless steel tubing ... 2-24 Cutting polymeric tubing ... 2-25 Assembling compression fittings ... 2-26 Connecting to the 432 Detector... 2-27 Installing the pulse dampener ... 2-27 Passivating the system ... 2-29 Verifying the detector ... 2-30 Calibration procedure... 2-30
3 Operating the Detector ... 3-1
Controls and indicators ... 3-2 Power switch ... 3-2 Display... 3-2Startup and shutdown ... 3-8 Startup procedure ... 3-8 Standby setup ... 3-9 Long-term storage... 3-9 Operating recommendations ... 3-9 Temperature equilibration ... 3-9 Base range... 3-10 Integrator output ... 3-10 Recorder output ... 3-10 Polarity ... 3-10 Eluent handling ... 3-10
4 Performing Ion Analysis ... 4-1
Fundamental considerations ... 4-2 Water ... 4-2 Containers ... 4-2 High-pH eluents... 4-3 Sample preparation ... 4-5 Configuring the system ... 4-5 Pulse dampener ... 4-6 Eluents for ion analysis ... 4-6 Preparing anion eluent... 4-7 Preparing cation eluent ... 4-8 Standards for ion analysis ... 4-8 Preparing anion standards... 4-9 Injecting anion standards... 4-10 Preparing cation standards... 4-12 Injecting cation standards... 4-14 Required materials ... 4-14 Injecting the standard ... 4-155 Maintenance ... 5-1
Routine maintenance ... 5-2 Replacing the fuse... 5-2Maintaining the flow cell... 5-3 Cleaning the detector exterior ... 5-6 Troubleshooting ... 5-6 When you call Waters service ... 5-6 Detector does not turn on ... 5-6 Startup diagnostics... 5-7 Power supply ... 5-7 Error messages ... 5-7 Troubleshooting procedure... 5-8 Removing bubbles ... 5-8
A Safety Advisories ... A-1
Warning symbols ... A-2 Task-specific hazard warnings... A-2 Specific warnings ... A-3 Caution symbol ... A-5 Warnings that apply to all Waters instruments ... A-6 Electrical and handling symbols ... A-12 Electrical symbols ... A-12 Handling symbols ... A-13B Specifications ... B-1
C Spare Parts ... C-1
D Ion Chromatography Methods ... D-1
General anion analysis using conductivity and UV detection ... D-2 Preparing eluent ... D-3 Preparing standards ... D-3 Preparing a sample... D-4Method detection limits... D-9 Quantitation accuracy ... D-10 Analyte recovery ... D-10 Example of use ... D-11 Using direct UV detection ... D-11 Preparing lithium borate/gluconate 50X stock concentrate ... D-13 Preparing lithium borate/gluconate eluent ... D-14 Alkali and alkaline earth cations, ammonium, and amines ... D-15 Preparing eluent ... D-16 Preparing standards ... D-16 Preparing a sample... D-17 Empower data processing method ... D-18 Method detection limits... D-19 Examples of use ... D-20 Preparing stock reagent ... D-21
E Validation Support ... E-1
Validation regulation overview ... E-2 Waters regulatory compliance support ... E-2 Basic operation... E-2 Instrument maintenance... E-3 Additional Waters support ... E-3Index ... Index-1
1 Introduction
Contents
Topic Page
Features 1-2
Method of operation 1-3
Ion detection theory 1-4
Features
The Waters® 432 Conductivity Detector is specifically designed to be
integrated into chromatographic systems. The following features contribute to its performance in measuring the conductivity of column eluents:
• Unique 5-electrode flow cell design
• Heat exchanger and a built-in automatic temperature control system for stable operation
• Auto baseline/auto zero
• External recorder/integrator and chart mark connections
• Three time constant selections
• “Leak-detected” alarm signal Waters 432 conductivity detector
TP01268
IN OUT
Waters 432
Conductivity Detector
Method of operation
This section discusses the method of operation of the 432 Detector. Additional descriptive information appears in these sections:
• “I/O signal descriptions” on page 2-8
• “Controls and indicators” on page 3-2
• Appendix B
Measurement technique
The 432 Detector responds to all ions present in the flow cell, since all ions in solution conduct electricity. This allows the 432 Detector to detect a wide variety of sample ions.
The 432 Detector eliminates the eluent’s contribution to conductivity with an electronic technique called baseline suppression. The detector measures the eluent conductivity and assigns it a value of zero. Thus, any sample ions appear as positive or negative measurements, relative to the baseline.
The temperature of an ionic solution affects the conductivity of the ions.
Generally, a solution’s conductivity rises about 2% for every degree Celsius of temperature increase. The special flow cell heater in the 432 Detector
minimizes the effect of ambient temperature fluctuations on measurement accuracy.
Flow cell design
The flow cell in the 432 Detector contains five electrodes connected in a measuring circuit: two reference electrodes, two detection electrodes, and a guard electrode that provides a local electrical “ground”. Column eluent flows through the heater to attain the set temperature, and then flows through the cell, directly contacting the electrodes. The 5-electrode design permits
measurement of conductivity to be made with a very low current at the detection electrodes. The low current employed eliminates impedance and other problems associated with simpler designs, and results in a stable baseline and an extended range of linearity.
Flow cell schematic
Ion detection theory
The conductance of a solution of known concentration can be calculated using the following equation:
G = measured conductance of the solution, in Siemens (1 S = ohm−1)
C = concentration in equivalents per 1000 cm3 1
3 2
Flow Cell Block (heated)
Fluid Outlet 1= Reference Electrodes 2= Detection Electrodes 3= Guard Electrode
1=Reference electrodes
2=Detection electrodes 3=Guard electrode
Flow cell block (heated)
Fluid outlet
G λC 10–3 ---
=
The table below lists the equivalent conductances of some common ions.1 Concentrations above 10-5 to 10-3 N, generally exhibit decreased equivalent conductance due to interionic effects.
1. Henry H. Bauer et al., eds. “Instrumental Analysis,” Allyn and Bacon, Boston (1978), p. 115. Reprinted with permission from the publisher.
Limiting equivalent conductance of ions in water at 25 °C
Cations l + Anions λ —
H + 349.8 OH − 198.6
Li + 38.6 F − 55.4
Na + 50.1 Cl − 76.4
K + 73.5 Br − 78.1
Rb + 77.8 I − 76.8
Ag + 61.9 NO
3 − 71.5
NH4
+ 73.3 ClO3 − 64.6
(CH3)2NH2 + 51.8 ClO4 − 67.4
Hg 2+ 53.0 IO4 − 54.5
Mg 2+ 53.1 Formate 54.6
Ca 2+ 59.5 Acetate 40.9
Ba 2+ 63.6 Benzoate 32.4
Cu 2+ 53.6 SO4 2− 80.0
Zn 2+ 52.8 CO3
2− 69.3
La 3+ 69.7 Fe(CN)6 4− 111.0
Ce 3+ 69.8
2 Installing the Detector
This chapter guides you through the following steps in preparing the 432 Detector for operation in a chromatographic system:
• Selecting an installation site that satisfies the detector’s power and environmental requirements
• Unpacking and inspecting the 432 Detector and accompanying items
• Connecting the detector to your AC power supply
• Connecting the detector electrically to the other components of your chromatographic system
• Connecting the detector inlet to the column and the detector outlet to a waste receptacle (and, if required, installing the pulse
dampener)
• Passivating the detector and other post-column fluid path components
After you have successfully completed this chapter, familiarize yourself with the information in “Controls and indicators” on page 3-2. When you are ready to operate the detector, perform the startup procedure
described in “Startup and shutdown” on page 3-8.
Contents
Topic Page
Selecting the installation site 2-2
Unpacking and inspection 2-3
AC power connection 2-4
I/O signal connections 2-7
Making fluidic connections 2-23
Passivating the system 2-29
Verifying the detector 2-30
Selecting the installation site
Operating environment
The 432 Detector operates in any standard laboratory environment that provides suitable electrical power and remains within the following ranges:
• Temperature: 5 to 35 °C (40 to 95 °F)
• Humidity: 20 to 80%, noncondensing
Install the instrument in a clean area that is free from exposure to:
• Temperature or humidity extremes, which can be found near direct sunlight, heat registers, and air conditioning vents
• Strong electromagnetic radiation, such as from large motors or arcing contacts
• Appreciable shock or vibration
Required space
The 432 Detector requires bench space that measures approximately:
• 10 inches (25 cm) high
• 14 inches (34 cm) wide
• 24 inches (60 cm) deep
Power requirements
The 432 Detector requires:
• One properly grounded AC voltage outlet.
• Correct voltage and fuse selections as shown in the table titled “Nominal operating voltage” on page 2-6.
Caution: Make sure that air can circulate freely through the ventilation slots on both side panels.
Unpacking and inspection
Unpacking
The 432 Detector is shipped in one carton that contains the following items:
• Waters 432 Conductivity Detector
• Startup Kit
• Validation certificate
• Waters 432 Conductivity Detector Operator’s Guide
• Packing list
• Declaration of conformity
Tip: If you purchased the 432 Detector as part of an ion/liquid chromatograph system, a Waters representative will perform the installation and startup.
To unpack the 432 Detector:
1. Locate the packing list.
2. Unpack the contents of the shipping carton and check the contents against the packing list to make sure that you received all items.
3. Check the contents of the Startup Kit against the Waters 432 Conductivity Detector Startup Kit List.
4. Save the shipping carton for future transport or shipment.
Inspection
Inspect all items. If you find any damage or discrepancy, immediately contact the shipping agent and Waters. For more information about the instrument warranty, refer to Waters Licenses, Warranties, and Support.
If the shipment is complete and undamaged, record the installation date and serial number of the 432 Detector in the spaces provided in Appendix C.
AC power connection
Power cord
The power connector is located on the lower-right corner of the rear panel. If a power plug other than the one supplied is needed for your location, consult the table titled “Power cord wire identification” on page 2-5 and observe the existing applicable regulations.
Warning: To avoid a potential fire hazard and damage to the 432 Detector, make sure that the voltage selector in the power connector is set correctly to match the available AC power source, and that the correct fuses are installed before you apply AC power.
Rear panel
The 432 Detector can be adapted to operate within two voltage ranges at 50 or 60 Hz. The table below describes these voltage ranges and the fuse value that is appropriate to each.
Power cord wire identification
Wire (USA) Wire (International) Connection
Black Brown Hot
White Blue Neutral
Green Green/Yellow Ground (Earth)
IEEE DIP switch cover
Required material
You need a flat-blade screwdriver to perform this procedure.
Procedure
To change the operating voltage setting:
1. Remove the power cord from its connector on the rear panel of the controller and pry open the power connector cover with a flat-blade screwdriver.
2. Remove the voltage selection barrel and locate the correct voltage setting.
3. Reinstall the voltage selection barrel so the desired voltage setting appears through the window when you close the power connector cover.
Nominal operating voltage Nominal Voltage (VAC) Fuse
100/120 T 2A
220/240 T 1A
Warning: To avoid the possibility of electrical shock, turn off the front panel power switch and unplug the power cord.
Changing the voltage setting
4. Determine if you need to change the fuses (see the table titled “Nominal operating voltage” on page 2-6). All units are supplied with two 2-A fuses installed for 100/120 volt operation. If you operate the unit on 220/240 volt power, change the fuse as outlined in “Replacing the fuse” on page 5-2.
5. Reinstall the power connector cover and the power cord.
I/O signal connections
The 432 Detector is usually installed as an integral part of a data collection system. You can control the 432 Detector either locally from the keypad on the front panel or remotely from a PowerLine™ controller, such as the Waters 600S.
This section describes the detector’s I/O signals and how they connect to the following devices:
• PowerLine controller
• Empower™ or Millennium®32 software
• Data module
• SAT/IN™ module
• Chart recorder
TP01275
Voltage setting
• Device signalling the Chart Marker input
• Device signalling the Auto Zero input
I/O signal descriptions
The 432 Detector rear panel has an IEEE-488 connector for communication with a PowerLine controller, and a terminal strip for the input/output signals.
These signals are described in the table titled “I/O signal descriptions” on page 2-9.
Caution: To meet the regulatory requirements of immunity from
external electrical disturbances that may affect the performance of this instrument, do not use cables longer than 9.8 feet (3 meters) when connecting to the screw-type barrier terminal strips. In addition, ensure you always connect the shield of the cable to chassis ground at one instrument only.
I/O terminal strip
I/O signal descriptions
Terminal pairs Function
Rec (+ and –) Recorder output – A 10-mV full-scale analog output signal appears on these terminals. The measurement range is determined by the product of the Base Range and Sensitivity settings: for example, 500μS (base range) x 0.005 (sensitivity) = 2.5 μS full scale.
Int (+ and –) Integrator output – A 1-V full-scale analog output signal appears on these terminals. The measurement range is selectable:
10, 50, or 100 μS full scale.
Marker Out Marker output – A 1-second contact closure signal appears on these terminals when either of the following events occurs:
• The Chart Mark key on the keypad is pressed
• A contact closure signal occurs between the Marker In terminals
+ – + –
+ –
+ –
INT
REC
LEAK
MARKER IN
MARKER OUT
AUTO ZERO Int
Rec
Leak
Marker in
Marker out
Auto zero
Required material
To connect cables to the I/O terminals, use a small flat-blade screwdriver.
Other rear panel connections and DIP switch
In addition to the I/O terminal strip, the rear panel also contains the following items:
• IEEE-488 connector – Communication bus for use with a Waters PowerLine system controller, such as the Waters 600S.
• DIP switch – Sets the IEEE-488 address seen by the system controller.
• Ground lugs – Used to connect the 432 Detector to an earth ground connection and also used as a chassis ground connection to other system instruments.
PowerLine controller connections
The 432 Detector can be programmed remotely by a PowerLine controller (such as the Waters 600S) via the IEEE-488 data communications bus.
Leak Leak Alert output – A contact closure signal
appears on these terminals if a leak is detected inside the detector.
Auto Zero
(+ and –) Auto Zero input – The voltage at the Recorder and Integrator output terminals is set to the user-selected balance offset level when a contact closure occurs between these terminals.
Marker In
(+ and –) Marker input – A chart mark (~0.5 mV for 3
seconds) is added to the Recorder output signal when a contact closure signal appears between these terminals.
I/O signal descriptions (Continued) Terminal pairs Function
Procedure
To connect the 432 Detector to a PowerLine controller:
1. Turn off the PowerLine controller and the 432 Detector.
2. Plug one end of the IEEE-488 cable (included in the Startup Kit) into the bus connector on the rear panel of the 432 Detector (see the figure “Rear panel” on page 2-5) and the other end of the cable into the bus connector on the PowerLine controller.
3. Remove the DIP switch cover (see the figure “Rear panel” on page 2-5) using a 2.5-mm Allen wrench.
4. Refer to the table titled “IEEE-488 DIP switch setting” on page 2-12 to set the DIP switches on the rear panel of the 432 Detector (see the figure
“IEEE-488 address switch” on page 2-11) to a unique IEEE-488 address between 2 and 29.
5. After you set the DIP switches, reinstall the DIP switch cover.
Tip: To operate the 432 Detector in local mode, press the front panel Remote key. The illuminated light above the key will go out.
IEEE-488 address switch
1 2 3 4 5
O F F
1 2
4
8 16
Switch 5 Switch 1
(Address 8 Shown)
The IEEE-488 address DIP switch employs positive logic to determine the address of the 432 Detector from the switch settings. The table below shows the settings for valid addresses.
IEEE-488 DIP switch setting IEEE-488
address
DIP switch settings
1 2 3 4 5
2 OFF ON OFF OFF OFF
3 ON ON OFF OFF OFF
4 OFF OFF ON OFF OFF
5 ON OFF ON OFF OFF
6 OFF ON ON OFF OFF
7 ON ON ON OFF OFF
8 OFF OFF OFF ON OFF
9 ON OFF OFF ON OFF
10 OFF ON OFF ON OFF
11 ON ON OFF ON OFF
12 OFF OFF ON ON OFF
13 ON OFF ON ON OFF
14 OFF ON ON ON OFF
15 ON ON ON ON OFF
16 OFF OFF OFF OFF ON
17 ON OFF OFF OFF ON
18 OFF ON OFF OFF ON
19 ON ON OFF OFF ON
20 OFF OFF ON OFF ON
21 ON OFF ON OFF ON
22 OFF ON ON OFF ON
23 ON ON ON OFF ON
PowerLine operation
Under PowerLine control, the 432 Detector is recognized as a 431 Detector and it retains the functionality of the 431 Detector with the following differences:
• The Balance field on the detector setup page of the PowerLine controller affects the Integrator Balance and the Integrator Output only.
• When you press the Setup key on the controller, the selected Balance value is sent to the 432 Detector from the PowerLine controller.
However, the 432 Detector output does not change to the selected balance until the detector is autozeroed by a contact closure at the Auto Zero input terminals on the rear panel (remote or local mode) or when you press the Auto Zero key on the front panel (local mode only).
Under PowerLine control, the 432 Detector retains the full functionality of local mode operation, except for the following differences:
• The Recorder Sensitivity ranges of 0.0002 and 0.0001 are not accessible.
• The Integrator Sensitivity ranges are not accessible.
• The 432 Detector does not automatically perform an Auto Zero after an Auto Base routine has occurred.
Empower and Millennium
32connections
Empower and Millennium32 software perform data acquisition, processing, and management of chromatographic information. This software requires the detector’s analog signal to be converted to a digital form.
27 ON ON OFF ON ON
28 OFF OFF ON ON ON
29 ON OFF ON ON ON
IEEE-488 DIP switch setting (Continued) IEEE-488
address
DIP switch settings
1 2 3 4 5
Empower and Millennium32 are menu-driven applications specifically designed by Waters for chromatographers. Use the software to:
• Acquire data
• Process data
• Generate and print reports
• Store information (or data) in a central area and share this information with users who have proper security access
To connect the 432 Detector to an Empower or Millennium32 computer, be sure to:
• Connect the Bus Satellite Interface (SAT/IN) module to the Bus
Laboratory Acquisition and Control/Environment (LAC/E™) card in the Empower computer, Millennium32 computer, acquisition client, or LAC/E32.
• Connect the 432 Detector to the Bus SAT/IN module (Channel 1 or 2).
• Remove the IEEE-488 cable from the rear panel of the 432 Detector, if it is connected.
The 432 Detector is in local mode when it is connected to an Empower and Millennium32 computer.
Bus SAT/IN module
The Waters Bus SAT/IN module translates analog signals into digital form. It then transmits these digital signals to the Bus LAC/E card inside the
workstation, acquisition client, or LAC/E32.
Bus SAT/IN module (front panel)
Tip: To prevent damage to the unit, always disconnect the power cord at either the wall outlet or the power supply before you attach or remove the power connection to the Bus SAT/IN module. The Bus SAT/IN module does not have a power switch.
Connecting the Bus SAT/IN module to the Bus LAC/E card
The Bus SAT/IN module connects to the Bus LAC/E through an I/O distribution box.To connect the Bus SAT/IN module to the Bus LAC/E card:
1. Use the I/O distribution cable to connect the I/O distribution box to the 9-pin I/O distribution port on the Bus LAC/E card at the back of the Millennium32 computer.
2. Use a serial cable to connect the data terminal on the back of the Bus SAT/IN to a port of the I/O distribution box.
3. Configure the serial port for the Bus SAT/IN module as described in the Empower or Millennium32 installation and configuration guides.
1 2 3 4 5 6 7 8 CHANNEL 1 CHANNEL 2
IN OUT IN OUT CH1
EVENTS CH2
+ – Waters SAT/IN Module
CH1 CH 2 OK
+ –
Bus SAT/IN to Bus LAC/E connections
AC to DC Converter I/O Distribution Por t (9-pin)
of Bus LAC/E Card
I/O Distribution Box
Connect SAT/IN to Port 1 on the I/O Distribution Box
Modified Modular Jack Connections I/O Distribution
Cable
PWR DATA BCD
SAT/IN Module Rear Panel
Serial Cable
Connecting the Bus SAT/IN module to the 432 Detector
The Bus SAT/IN module connects to the 432 Detector as shown below. Refer to the procedure following the figure and the table titled “Bus SAT/IN cable connections” on page 2-18 for complete details.
Bus SAT/IN to 432 Detector connections
To connect the 432 Detector to the Bus SAT/IN module:
1. Connect the white wire of the analog cable (included with the Bus SAT/IN module) to the Int + terminal on the rear panel of the 432 Detector. Connect the black wire to the Int – terminal.
Caution: To prevent damage to the unit, do not plug in the power cord of the Bus SAT/IN module until you perform all of the procedures
described in the Waters Bus SAT/IN Module Installation Guide.
+ – + –
+ –
+ –
INT
REC
LEAK
MARKER IN
MARKER OUT AUTO ZERO
TP01264
1 2 3 4 5 6 7 8 CHANNEL 1 CHANNEL 2
IN OUT IN OU T CH1
EVENTS CH2
+ – Waters SAT/IN Module
CH 1 CH
2 OK
Red Black
Waters 432 Detector
+ –
2. Connect the other end of the cable to either the Channel 1 or Channel 2 connector on the front panel of the Bus SAT/IN module.
3. Connect the Event In terminals of the channel you chose in the previous step to the Inject Start output signal of the Waters Alliance® solvent delivery system or the Waters 717plus (or equivalent) Autosampler.
4. Remove the IEEE-488 cable from the rear panel of the 432 Detector, if it is connected.
The connections from the 432 Detector to the Bus SAT/IN are summarized below.
Data module connections
This section describes how to connect the analog output signal from the 432 Detector to the Waters 746 Data Module.
Bus SAT/IN cable connections 432 Detector I/O
connector terminal Bus SAT/IN cable Bus SAT/IN connector
Int (+) White wire
Int (–) Black wire Channel 1 or 2
Caution: Remember to meet the regulatory requirements of immunity from external electrical disturbances that may affect the performance of this instrument, do not use cables longer than 9.8 feet (3 meters) when connecting to the screw-type barrier terminal strips. In addition, ensure you always connect the shield of the cable to chassis ground.
Analog signal
To send the analog output signal from the 432 Detector to a Waters data module, connect the signal cable in the 432 Detector Startup Kit as described below.
Marker out signal
The Marker Out terminals of the 432 Detector provide a contact closure output signal when either of the following events occurs:
• Chart Mark key is pressed
• Marker In terminals are shorted together
Use the signal to start a Waters 746 Data Module by connecting a signal cable to the module’s data cable.
Chart recorder connections
To connect the 432 Detector to a chart recorder:
1. Attach the Recorder cable (see Appendix C) to the 432 Detector REC output terminals, as indicated in the table titled “Chart recorder cable connections” on page 2-20.
Data module signal cable connections
Wire 432 Detector I/O
connector terminal 746 terminal
Red Int (+) (+)
Black Int (–) (–)
Shield Ground lug None
Data module chart mark cable connection
Wire 432 Detector I/O
connector terminal 746 cable
Either wire Marker Out Join to both Remote
Start wires (white and red)
Other wire Marker Out Green wire
2. Connect the cable shield to the ground lug on the 432 Detector rear panel.
3. Connect the other end of the cable to the 10-mV input terminals on the chart recorder.
Chart marker input connections
The 432 Detector accepts a chart mark (start inject) signal from the following devices:
• Waters 717plus Autosampler
• Any other device that provides a compatible switch closure
Waters 717plus Autosampler
To connect the 432 Detector to a Waters 717/717plus Autosampler, connect a signal cable as indicated in the table below.
Chart recorder cable connections
Wire 432 Detector I/O
connector terminal
Chart recorder terminal
Red Rec (+) Pen (+)
Black Rec (–) Pen (–)
Autosampler chart mark cable connections 432 Detector I/O
connector terminal Autosampler terminal
Marker In (+) Either Inject Start terminal of a pair
Marker In (–) Other Inject Start terminal of the same pair
Auto Zero input connections
The voltage at the Recorder and Integrator outputs is set to the user-selected balance offset level when a contact closure occurs between the Auto Zero terminals. This section describes how to connect the 432 Detector to the following devices (so that an auto zero occurs at the injection point):
• Waters 717plus Autosampler
• Any other device that provides a compatible switch closure
Waters 717plus Autosampler
To connect the 432 Detector to a Waters 717plus Autosampler, connect a signal cable as indicated in the table below.
Alliance Separations Module connections
Connect the detector to Waters Alliance Separations Modules, when it is not under the control of the Millennium32 software, to perform the following tasks:
• Auto-Zero on inject
• Chart mark on inject
• Method start
Generating Auto-Zero on inject
To generate the Auto-Zero function on the 432 Detector at the start of an injection, make the connections summarized in the table titled “Connections for generating Auto-Zero on inject” on page 2-22 and illustrated in the figure Autosampler Auto Zero cable connections
432 Detector I/O
connector terminal Autosampler terminal
Auto Zero (+) Either Inject Start terminal of a pair
Auto Zero (–) Other Inject Start terminal of the same pair
“Alliance Separations Module connections to the 432 Detector Auto-Zero on inject” on page 2-22.
Before you can generate an Auto-Zero from an Alliance Separations Module, you must configure the Auto-Zero signal at the 432 Detector front panel. The default Auto-Zero signal is Low.
Alliance Separations Module connections to the 432 Detector Auto-Zero on inject
Generating chart mark on inject
Connections for generating Auto-Zero on inject Alliance Separations Modules (B
inputs and outputs) 432 Detector (A inputs)
Pin 1 Inject Start Auto-Zero (+)
Pin 2 Inject Start Auto-Zero (–)
Inject start +
Inject start –
Ground Stop flow +
Stop flow –
Hold inject 1+
Hold inject 1 –
Hold inject 2 +
Hold inject 2 –
Ground Chart out +
Chart out –
Waters Alliance B (inputs and outputs)
10 Auto-Zero - 9 Auto-Zero + 8 Ground 7 Chart Mark - 6 Chart Mark + 5 Lamp On/Off - 4 Lamp On/Off + 3 Ground 2 Inject Start - 1 Inject Start +
Waters 432 Detector A (inputs)
+ – + –
+ –
+ –
Int
Rec
Marker in
Auto Zero Leak
Marker out
“Alliance Separations Module connections to the 432 Detector chart mark on inject” on page 2-23.
Before you can generate a chart mark from an Alliance Separations Module, you must configure the chart mark signal at the front panel. The default chart mark signal is Low.
Alliance Separations Module connections to the 432 Detector chart mark on inject
Making fluidic connections
Fluid lines to a column and waste container connect to the front of the 432 Detector, as shown in the figure “Fluid connections” on page 2-24. To make these connections:
Connections for generating chart mark on inject Alliance Separations Modules (B
inputs and outputs) 432 Detector (A Inputs)
Pin 1 Inject Start Marker In (+)
Pin 2 Inject Start Marker In (–)
Inject start +
Inject start –
Ground Stop flow +
Stop flow –
Hold inject 1+
Hold inject 1 –
Hold inject 2 +
Hold inject 2 –
Ground Chart out +
Chart out –
Waters Alliance B (inputs and outputs)
10 Auto-Zero - 9 Auto-Zero + 8 Ground 7 Chart Mark - 6 Chart Mark + 5 Lamp On/Off - 4 Lamp On/Off + 3 Ground 2 Inject Start - 1 Inject Start +
Waters 432 Detector A (inputs)
+ – + –
+ –
+ –
INT
REC
LEAK
MARKER IN
MARKER OUT AUTO ZERO
+ – + –
+ –
+ –
Int
Rec
Marker in
Auto Zero Leak
Marker out
• Cut the tubing.
• Assemble compression fittings and ferrules.
• Connect the tubing to the detector.
This section will guide you through each of these procedures.
Fluid connections
Cutting stainless steel tubing
You need the following tools to cut stainless steel tubing:
• A file with cutting edge
• Two cloth- or plastic-covered pliers
Caution: Conductivity detection is sensitive to flow rate fluctuations. If you use a non-Waters pump or a Waters pump without the SILK
microflow compensation algorithm, you must install the pulse dampener kit supplied in the Startup Kit for optimum performance. Refer to the installation procedure in this section.
In From Column IN OUT
Out To Waste (18 inches.
0.009-inch I.D.)
Waters 432
Conductivity Detector
Out to waste
(18 inches, 0.000-inch ID) In from column
To cut the tubing:
1. Measure the length of 1/16-inch OD, 0.009-inch ID, stainless steel tubing you need to make the following connections:
• Column to the detector inlet
• Detector outlet to a suitable waste container
2. Use a file with a cutting edge to scribe the circumference of the tubing at the desired length.
3. Grasp the tubing on both sides of the scribe mark with cloth-covered pliers. Gently work the tubing back and forth until it separates.
4. File the ends smooth.
Cutting polymeric tubing
Waters chromatography systems are supplied with a tubing cutter (similar to the one in the figure “Cutting polymeric tubing” on page 2-26) to facilitate cutting polymeric tubing. This section presents the recommended procedure for using the tubing cutter.
Tip: To avoid bandspreading caused by angled cuts, always use a tubing cutter. Angled cuts leave unswept dead volumes at the connection junction due to the poor fit of the tubing against the connector or port.
To cut a length of polymeric tubing:
1. Estimate the length of tubing required to connect the components. Allow slack so that the tubing is not pulled tightly around sharp corners.
2. Insert the tubing into the cutter so that the tubing extending from the metal side is the length required. Use the proper hole to have a snug enough fit so that the tubing is not flexed by the blade when you cut it.
Cutting polymeric tubing
3. Press down on the razor blade to cut the tubing. Discard the excess tubing that extends from the clear side of the cutter.
4. Inspect the cut for burrs or scratches and for the perpendicularity of the cut.
Assembling compression fittings
To assemble each compression fitting:
1. Slide the compression screw over the tubing end, followed by the ferrule.
2. Mount the ferrule with its taper end facing the end of the tubing.
Ferrule and compression screw assembly Compression
Screw
Ferrule Compression screw
Ferrule
Connecting to the 432 Detector
To make connections at the column outlet and detector inlet, and at the detector outlet:
1. Install a compression screw and then a ferrule on the length of
0.009-inch tubing from the column outlet. Use stainless steel fittings on stainless steel tubing and PEEK fittings on PEEK tubing.
Tip: If you are using a column with 1/4–28 end fittings and there is a length of tubing with 1/4–28 fittings on each end, use the 1/4–28 to Z-detail adapter (included in the Startup Kit) to connect this tubing to the tubing that leads to the detector inlet.
The Waters IC-Pak C column comes supplied with a length of tubing that has a 1/4–28 fitting on one end (column outlet) and a Waters compression screw and ferrule on the other end (detector inlet).
2. Push the free end of the tubing as far as it will go into the IN fitting on the 432 Detector. While you hold it there, use a 5/16-inch open-end wrench to tighten the compression screw 3/4-turn past finger-tight.
Tip: The 432 Detector and IC-Pak series of columns have very deep ferrules.
3. Remove the compression screw and tubing from the connection and verify that fluid can flow freely.
4. Reconnect the tubing to the IN fitting, making sure to push the tubing all the way into the fitting.
5. Install a ferrule on an 18-inch length of 0.009-inch tubing and connect it to the OUT connection on the 432 Detector. Use stainless steel fittings on stainless steel tubing and PEEK fittings on PEEK tubing.
6. Place the other end of the tube in a waste container. If you are using any Teflon tubing, attach it after the stainless steel or PEEK tubing.
Installing the pulse dampener
To achieve the best performance from the 432 Detector in a chromatographic system with a non-Waters pump, Breeze™ software, or Waters HPLC 515 Pump, you must install the pulse dampener kit supplied in the Startup Kit.
The pulse dampener is not required if you are using a Waters 2695 Separations Module.
To install the pulse dampener between the pump and the injector:
1. Assemble the pulse dampener (see the figure “Pulse dampener” on page 2-28) using the instructions in the pulse dampener kit.
2. Connect the large-ID (0.020-inch) tubing to the pump outlet using a stainless steel compression screw and ferrule.
3. Connect the small-ID (0.009-inch) tubing to the injector inlet using a stainless steel compression screw and ferrule.
4. Disconnect the tubing from the injector inlet.
5. Pump ASTM Type I reagent water at £ 2 mL/min through the pulse dampener assembly until you see a constant stream exiting from the restrictor assembly outlet line.
6. Reconnect the tubing to the injector inlet.
Pulse dampener
0.020-inch I.D.
Tubing
0.009 inch I.D.
Tubing
To Injector U nion
From Pum p Union To injector
0.009-inch ID tubing 0.020-inch ID tubing
From pump
Passivating the system
Passivating the system removes potential contamination from the wetted surfaces of all system components. Perform passivation on a new system, and subsequently, whenever you suspect that contamination may have occurred.
See “Troubleshooting” on page 5-6, for help diagnosing performance problems.
Use this procedure for Waters hardware only. For other equipment, check with the manufacturer before you continue with this procedure.
To passivate the system:
1. Replace the column with a union fitting.
2. If the system is not new, flush it thoroughly with ASTM Type I reagent water to remove any residual solvents or salts.
3. Connect the power cord to the 432 Detector and plug the other end into an AC power outlet. Push the 432 Detector power switch to turn on the instrument.
4. Prime the pump with 6 N nitric acid (HNO3) and run it at a flow rate of 1.2 mL/min for 20 minutes to passivate all the wetted parts of the detector. Press the Clear key to stop the overrange alarm.
5. Stop the pump.
6. Remove the inlet line from the nitric acid and place it in ASTM Type I reagent water.
7. Flush the system using one of the following methods:
• Prime and start the pump, then flush it with ASTM Type I reagent water at 1.2 mL/min until you observe a consistent reading of less than 20 μS (base range set to 50 μS).
Caution: If you are installing the 432 Detector into an existing Waters system, replace the pump seals before you passivate. Use the new pump seals supplied in the Startup Kit and refer to the replacement procedure in the pump manual.
Warning: To avoid chemical hazards, always wear safety glasses and gloves when you are using solvents.
• Flush the system overnight with 100% methanol at a reduced flow rate. By the next morning the system will be passivated and ready for use.
Tip: If you are using a pump with seal-wash capability, skip step 8.
8. Use a syringe to flush the back of the pump seals and pistons by slowly running about 5 mL of water into the top hole in the baseplate of the pump heads. Place a tissue under the baseplates to absorb the water.
9. Set the pump flow rate to 0.0 mL/min. It is not necessary to turn off the 432 Detector unless it will be idle for an extended period (14 days).
For best results, always leave the power on to maintain cell temperature; it takes a minimum of 2 to 3 hours once the detector is turned on to equilibrate the flow cell at the selected operating temperature.
Verifying the detector
This procedure is a guideline for verifying that the detector works correctly within its expected operational range. The detector is calibrated before shipping, and recalibration is not normally required.
Verify the detector when any of these conditions apply:
• When you replace the flow cell
• To verify accuracy
• When you make adjustments
Calibration procedure
Tip: You need solution of 1 mM potassium chloride (KCl) to calibrate the detector.
Tip: Waters suggests one of its Technical Service Representatives perform this procedure.
To perform the calibration procedure:
1. Turn on the 432 Detector and set the temperature control to 35 °C.
4. Pump 1 mM KCl solution through the detector (without a column in place).
5. Verify that the front panel output is 147 μS ± 5 μS.
3 Operating the Detector
This chapter contains:
• A description of front panel controls and displays
• Procedures for starting up, shutting down, and long-term storage
• Recommended operating practices
Contents
Topic Page
Controls and indicators 3-2
Startup and shutdown 3-8
Operating recommendations 3-9
Controls and indicators
The figure below illustrates the controls and indicators on the front panel of the 432 Detector.
Front panel
Power switch
The power switch (located in the lower-right corner of the front panel) controls power to the 432 Detector. Upon startup, an initialization routine verifies the data in ROM memory, tests RAM memory function, and checks for any internal leakage or an eluent conductivity over-range condition.
Remote Temp. Pol. Chart
Mark
7 8 9
4 5 6
1 2 3
0 . Clear
Enter Shift
Resp. Bal.
Base Range
Sens.
Range Auto
Base Auto
Zero CONDUCT
( S/cm) BASE
( S/cm/FS) SENS
274 500 0.0005
ON OFF
IN OUT
Waters 432
Conductivity Detector
briefly. If any error conditions are detected during startup or normal operation, the appropriate error message is displayed.
The main screen shows the measured conductivity, as well as the base range and sensitivity settings. When you set an operating parameter, the display shows the selected or entered value.
Error messages
A corresponding error message is displayed if one of the following conditions occurs:
• ROM/RAM error (checked during startup only) Error: ROM/RAM
• Leakage detected Error: Leak
• Temperature control failure Error: Temp
• Over-range (above base range setting) Error: Over Range
• Overflow (above 10,000 μS) Error: Over Flow
Press the Clear key to clear an error alarm and message. For a continuing error condition, the error message remains after the audio alarm is cleared.
Keypad
Use the keypad to control the operation of the 432 Detector. The table titled
“Key descriptions” on page 3-4 describes the function of each key.
Tip: Three keys (Balance, Sensitivity Range, and the numeral 1) perform an alternate function when they are preceded by the Shift key.
Key descriptions
Key Function
Remote key: Toggles between local and remote operating modes. In remote mode, the light above the key is on and all other front panel controls are
disabled.
Polarity key: Toggles the polarity of the signal to the external chart recorder and integrator. When positive polarity is selected, the light above the key is
illuminated.
Base Range key: Sets the base sensitivity range of the 432 Detector to the appropriate value for the eluent being used. The base sensitivity is set to one of ten steps, from 10 μS (maximum gain) to 10,000 μS, using the Up and Down keys or the numeric keypad.
Sensitivity Range key: Sets the sensitivity range multiplier of the 432 Detector. The sensitivity range has twelve steps, from 0.0001 (maximum sensitivity) to 1.0 (available only with 100μS multiplier setting), and is set using the Up and Down keys or the numeric keypad. The 10-mV full-scale recorder response is calculated by multiplying the Base Range by the Sensitivity Range to obtain a value of “x” μS / 10 mV FS. The recorder range is 1 to 0.0001 for the 100 μS setting and 0.1 to 0.0001 for the two lower settings.
Shift key then Sensitivity Range key: Sets the sensitivity range multiplier of the integrator to 100, 50, or 10 μS using the Up and Down keys or the numeric keypad; the integrator output is 100, 50, or 10 μS/1 V, respectively.
Remote
Pol.
Base Range
Sens.
Range
Balance key: Manually sets the offset (%) of the signal to the external chart recorder. (Use the numeric keypad or Up and Down keys.)
Shift key then Balance key: Manually sets the offset (%) of the signal to the integrator. (Use the numeric keypad or Up and Down keys.)
Shift key after Balance key: Changes the polarity of the offset. Allowable values are –100 to +100%.
Temperature key: Sets the temperature of the detection cell. Use the Up and Down keys or the numeric keypad to turn temperature control off (Setting 0) or select one of the following eight
settings: 30, 35, 40, 45, 50, 55, 60, or 65 °C. The light above the key is illuminated when the temperature control is on.
Response key: Sets the response time constant of the 432 Detector to optimize signal-to-noise ratio. Use the Up and Down keys or the numeric keypad to choose Setting 1 (Fast, 0.25 sec) for very narrow peaks, Setting 2 (Standard, 0.5 sec), or Setting 3 (Slow, 1.0 sec) to detect wider peaks. Setting 2 is used for most applications.
Auto Zero key: Automatically zeros the Recorder and Integrator signals to the specified Recorder Balance and Integrator Balance offsets, respectively.
Auto Base key: Automatically sets the base range of the 432 Detector to the appropriate value for the eluent being used. This is the next highest setting above the actual background conductivity of the eluent.
Key descriptions (Continued)
Key Function
Bal.
Temp.
Resp.
Auto Zero
Auto Base
Shift key: Press the Shift key before, not along with, other keys to access additional functions and also to change polarity when you set balance offset values.
When the Shift key is pressed, an asterisk (*) appears at the right side of the display; press Shift again to return to normal mode.
Shift key then Balance key: Displays the integrator balance offset value. When setting the balance offset, press Shift to change polarity.
Shift key then Sensitivity Range key: Displays integrator range value.
Shift key then 1 key: Displays the current, actual value of the chart recorder balance offset. Press Enter to return to the main screen.
Chart Mark key: When this key is pressed, a 1-second, 1-mV signal is sent to the Recorder
terminals and a 1-second contact closure is sent to the Marker Out terminals.
Enter key: When you manually set offsets, sensitivity range, or base range, pressing Enter records the displayed value and returns the display to the main screen. The Enter key is also used to access the beep setting function.
Clear key: Erases a value input from the keypad.
The Clear key is also used to clear an error alarm and message. For a continuing error condition, the error message remains after the audio alarm is cleared.
Up key: Increments the current parameter setting.
Key descriptions (Continued)
Key Function
Shift
Chart Mark
Enter
Clear
Beep function
You can set the 432 Detector to beep when a key is pressed and/or an error condition is detected.
Use the Clear key to stop an error alarm. For a continuing error condition, the error message remains after the beep is cleared.
To set the beep function, follow the procedure in the table below.
Tip: Since the void volume in many separations contains highly conductive counter-ions, the error alarm sounds upon each injection. See the table titled
“Setting the beep function” on page 3-7 to silence the beep-on-error alarm.
Down key: Decrements the current parameter setting.
Setting the beep function
Keystroke Key Function
1 Enter Accesses the beep function parameters.
2 . (decimal point)
3 Enter
4 1 Turns on the beep-on-error function.
0 Turns off the beep-on-error function.
5 1 Turns on the beep-on-keystroke function.
0 Turns off the beep-on-keystroke function.
6 Enter Saves settings and returns to the main screen.
Key descriptions (Continued)
Key Function
Startup and shutdown
Startup procedure
Perform the following procedure to start the 432 Detector. Typically, this procedure is done at the beginning of each workday.
Tip: This procedure assumes that the flow cell has stabilized at the selected temperature (minimum 2 to 3 hours). Standard practice is to leave the detector powered and with the temperature control on unless the instrument will be unused for several days.
Set the temperature at least 5 °C above the highest ambient temperature expected for the duration of the application.
1. Prime the pump with properly degassed eluent and set the flow rate to 1.2 mL/min or to the flow rate recommended for your particular column or application. Do not sparge eluents, since sparge gasses may contain ionic contaminants.
2. Set the response (time constant) to the desired setting by pressing the Response key. A standard setting (0.5 seconds) is preferred for most applications.
3. Set the base value by pressing the Auto Base key or by manually entering the base range that is the next highest setting above the eluent’s background conductivity.
4. Turn on the recorder/integrator and run the system until the baseline stabilizes.
5. Depending on whether you are using a recorder or an integrator, do one of the following actions:
• If you are using a 10-mV recorder connected to the Recorder terminals on the rear panel, select the desired sensitivity by pressing the Sensitivity Range key, then the appropriate Up or Down arrow key.
• If you are using an integrator connected to the Integrator terminals on the rear panel, select the desired sensitivity by pressing the Shift
6. Zero the recorder/integrator by pressing the Auto Zero key or have the Auto Zero terminals of the rear panel I/O terminal strip connected to your manual injector or autosampler.
The 432 Detector is now ready for operation.
Standby setup
To eliminate the need to allow time for the flow cell temperature to
equilibrate, leave the 432 Detector turned on at the end of the workday or workweek. Set the temperature control to the operating temperature and the pump flow rate to 0.01 to 0.1 mL/min (depending on the pump).
Long-term storage
If the 432 Detector is to be removed from a system for storage or if the system itself is to be stored for a long time, flush the detector/system with 100%
water, then 100% HPLC-grade methanol. Leave the methanol in the system after shutdown. If you are removing the 432 Detector from the system, seal the inlet and outlet bulkheads with dead-end fittings or a loop of tubing.
Operating recommendations
Observe the following recommendations for best detector performance.
Temperature equilibration
The 432 Detector should be powered up and set at the desired operating temperature for two to three hours before use. Select a temperature at least 5 °C above the highest ambient temperature expected during the duration of the application. The detector is usually set at 35 °C, but it should be set higher if the ambient temperature will exceed 30 °C.
You may choose to leave the 432 Detector powered up overnight at a flow rate of 0.01– 0.1 mL/min (depending on the pump) to minimize the daily
reequilibration time.
A drifting baseline is one indication that the temperature of the flow cell is not uniform across the flow cell or stable over time.
Base range
The Base Range is normally set at the next setting above the background conductivity of the eluent. For example, if the conductivity of borate/gluconate eluent is 270μS, set the Base Range to 500 μS.
Integrator output
The Integrator output is not attenuated; signals should be below 1 V. Set the Integrator output to 10μS/V for small signals or to 50 μS/V when you expect a signal greater than 10μS. If you are using the 432 Detector with chemical suppression, set the integrator output to 100 μS/V.
Recorder output
The Recorder output is attenuated and the Sensitivity Range should be adjusted to provide the appropriate output level.
Polarity
Signal polarity depends on eluent conductivity. If necessary, press the Polarity key to obtain peaks rather than dips.
Eluent handling
Replace your eluent reservoir filter regularly. When you analyze cations, use an all-plastic eluent reservoir filter. Filter and degas eluents to prolong column life, reduce pressure fluctuations, and decrease baseline noise. When you change eluents, flush the flow cell and associated tubing thoroughly with the new eluent.
4 Performing Ion Analysis
This chapter provides essential information about ion analysis
techniques. Two representative columns serve as typical examples: the Waters IC-Pak A for anions and the IC Pak C M/D for cations. The following topics are discussed:
• Fundamental considerations
• Configuring the system
• Selecting and preparing eluents
• Preparing and injecting standards
Also refer to the manufacturer’s manual for the particular column you are using. A recommended source for more information about ion analysis in general is Ion Chromatography: Principles and Applications by Paul R. Haddad and Peter E. Jackson, Elsevier Science Publishing, New York, 1990.
Contents
Topic Page
Fundamental considerations 4-2
Configuring the system 4-5
Eluents for ion analysis 4-6
Standards for ion analysis 4-8
