Agilent 5975 Series MSD Troubleshooting and Maintenance Manual Agilent Technologies
Notices © Agilent Technologies, Inc. 2012 Warranty No part of this manual may be reproduced in any form or by any means (including electronic storage and retrieval or translation into a foreign language) without prior agreement and written consent from Agilent Technologies, Inc. as governed by United States and international copyright laws. The material contained in this document is provided “as is,” and is subject to being changed, without notice, in future editions.
Contents 1 Introduction 5975 Series MSD Version Abbreviations Used 10 11 The 5975 Series MSD 13 MSD Hardware Description 15 Electron Ionization (EI) systems 16 Chemical Ionization (CI) systems 16 Changing modes 17 Important Safety Warnings Hydrogen Safety 18 20 Safety and Regulatory Certifications Cleaning/Recycling the Product Moving or Storing the MSD 2 25 28 28 General Troubleshooting Troubleshooting Tips and Tricks General Symptoms 31 Chromatographic Symptoms Mass Spectral Symptoms Pressu
3 CI Troubleshooting Common CI-Specific Problems 58 Troubleshooting Tips and Tricks Air Leaks 60 Pressure-Related Symptoms 4 59 64 Signal-Related Symptoms 68 Tuning-Related Symptoms 77 General Maintenance Before Starting 84 Maintaining the Vacuum System To Remove the MSD Covers 89 90 To Connect the Micro-Ion Vacuum Gauge To Move or Store the MSD 92 94 To Check and Add Foreline Pump Oil To Drain the Foreline Pump 98 To Refill the Foreline Pump 100 96 To Check the Diffusion Pump Flui
To Remove the Micro-Ion Vacuum Gauge 116 To Reinstall a Micro-Ion Vacuum Gauge To Lubricate the Side Plate O-Ring 118 To Lubricate the Vent Valve O-Ring 120 To Remove the Diffusion Pump 122 To Replace the Diffusion Pump Fluid To Reinstall the Diffusion Pump 129 To Reinstall the Foreline Gauge 130 131 Maintaining the GC/MSD Interface Maintaining the Electronics 5 124 127 To Remove the Foreline Gauge Maintaining the Analyzer 117 153 157 CI Maintenance To Clean the CI Ion Source 164 To M
Diffusion pump system 178 Turbo pump system 178 Analyzer Chamber 179 Diffusion pump version 179 Turbo pump version 179 Side Plate 180 Vacuum Seals 182 Foreline Gauge 184 Diffusion Pump and Fan Turbo Pump and Fan 185 191 Calibration Valves and Vent Valve Micro-Ion Vacuum Gauge 7 195 Analyzer Overview 198 EI Ion Source 200 CI Ion Source 202 Filaments 204 Other Source Elements 206 Quadrupole Mass Filter 208 Detector 211 Analyzer Heaters and Radiators 8 192 213 Electronics Local Cont
LAN/MS Control Card Power Supplies 223 224 Back Panel and Connectors Interfacing to External Devices 9 225 228 Parts To Order Parts Electronics 232 233 Local Control Panel Vacuum System Analyzer 238 240 250 EI GC/MSD Interface 259 Consumables and Maintenance Supplies CI Parts Index 260 265 271 5975 Series MSD Troubleshooting and Maintenance Manual 7
5975 Series MSD Troubleshooting and Maintenance Manual
Agilent 5975 Series MSD Troubleshooting and Maintenance Manual 1 Introduction 5975 Series MSD Version 10 Abbreviations Used 11 The 5975 Series MSD 13 Physical description 13 Local control panel 13 Vacuum gauge 13 MSD Hardware Description 15 Important Safety Warnings 18 Many internal parts of the MSD carry dangerous voltages 18 Electrostatic discharge is a threat to MSD electronics 18 Many parts are dangerously hot 19 The oil pan under the standard foreline pump can be a fire hazard 19 Hydrogen Safety 20 Da
1 Introduction 5975 Series MSD Version 5975 Series MSDs are equipped with a diffusion pump or one of two turbomolecular (turbo) pumps. The serial number label displays a product number (Table 1) that indicates what kind of MSD you have.
Introduction 1 Abbreviations Used The abbreviations in Table 2 are used in discussing this product. They are collected here for convenience.
1 12 Introduction Table 2 Abbreviations (continued) Abbreviation Definition NCI Negative CI OFN Octafluoronaphthalene (calibrant) PCI Positive CI PFDTD Perfluoro-5,8-dimethyl-3,6,9-trioxydodecane (calibrant) PFHT 2,4,6-tris(perfluoroheptyl)-1,3,5-triazine (calibrant) PFTBA Perfluorotributylamine (calibrant) Quad Quadrupole mass filter RF Radio frequency RFPA Radio frequency power amplifier Torr Unit of pressure, 1 mm Hg Turbo Turbomolecular (pump) 5975 Series MSD Troubleshooting
Introduction 1 The 5975 Series MSD The 5975 Series MSD is a stand-alone capillary GC detector for use with Agilent Gas Chromatographs (Table 3).
1 Introduction The gauge is required for chemical ionization (CI) operation. Table 3 5975 series MSD models and features Model Feature G3170A G3175A G3171A G3176A G3172A G3174A High vacuum pump Diffusion Standard turbo Performance turbo Performance turbo Optimal He column flow mL/min 1 1 1 to 2 1 to 2 Maximum recommended gas flow mL/min* 1.5 2.0 4.0 4 Maximum gas flow, mL/min† 2 2.4 6.5 6.5 Max column id 0.25 mm (30 m) 0.32 mm (30 m) 0.53 mm (30 m) 0.
Introduction 1 MSD Hardware Description Figure 1 is an overview of a typical GC/MSD system.
1 Introduction Electron Ionization (EI) systems EI systems ionize sample molecules by bombarding them with electrons. The ions, including fragments, are drawn into the quadrupole analyzer where they are separated by their mass-to-charge (m/z) ratios and detected. Chemical Ionization (CI) systems CI systems use a reagent gas as an intermediate between the electrons and the sample. CI is more gentle than direct electron bombardment.
Introduction 1 Changing modes Switching back and forth between CI and EI sources takes less than an hour, although a 1- to 2-hour wait is required to purge the reagent gas lines and bake out water and other contaminants. Switching from PCI to NCI requires about 2 hours for the ion source to cool.
1 Introduction Important Safety Warnings There are several important safety notices to always keep in mind when using the MSD. Many internal parts of the MSD carry dangerous voltages If the MSD is connected to a power source, even if the power switch is off, potentially dangerous voltages exist on: • The wiring between the MSD power cord and the AC power supply, the AC power supply itself, and the wiring from the AC power supply to the power switch.
1 Introduction Many parts are dangerously hot Many parts of the GC/MSD operate at temperatures high enough to cause serious burns. These parts include but are not limited to: • The inlets • The oven and its contents • The detector • The column nuts attaching the column to an inlet or detector • The valve box • The foreline pump Always cool these areas of the system to room temperature before working on them. They will cool faster if you first set the temperature of the heated zone to room temperature.
1 Introduction Hydrogen Safety WARN I NG The use of hydrogen as a GC carrier gas is potentially dangerous. WARN I NG When using hydrogen (H2) as the carrier gas or fuel gas, be aware that hydrogen gas can flow into the GC oven and create an explosion hazard. Therefore, be sure that the supply is turned off until all connections are made and ensure that the inlet and detector column fittings are either connected to a column or capped at all times when hydrogen gas is supplied to the instrument.
Introduction 1 Dangers unique to GC/MSD operation Hydrogen presents a number of dangers. Some are general, others are unique to GC or GC/MSD operation. Dangers include, but are not limited to: • Combustion of leaking hydrogen. • Combustion due to rapid expansion of hydrogen from a high-pressure cylinder. • Accumulation of hydrogen in the GC oven and subsequent combustion (see your GC documentation and the label on the top edge of the GC oven door).
1 Introduction Table 4 22 Hydrogen accumulation mechanisms (continued) Mechanism Results Mass spectrometer automated shutoff valves closed Some mass spectrometers are equipped with automated diffusion pump shutoff valves. In these instruments, deliberate operator action or various failures can cause the shutoff valves to close. shutoff valve closure does not shut off the flow of carrier gas. As a result, hydrogen may slowly accumulate in the mass spectrometer.
1 Introduction WARN I NG Once hydrogen has accumulated in a mass spectrometer, extreme caution must be used when removing it. Incorrect startup of a mass spectrometer filled with hydrogen can cause an explosion. WARN I NG After a power failure, the mass spectrometer may start up and begin the pumpdown process by itself. This does not guarantee that all hydrogen has been removed from the system or that the explosion hazard has been removed.
1 Introduction Operating precautions • Turn off the hydrogen at its source every time you shut down the GC or MSD. • Turn off the hydrogen at its source every time you vent the MSD (do not heat the capillary column without carrier gas flow). • Turn off the hydrogen at its source every time shutoff valves in an MSD are closed (do not heat the capillary column without carrier gas flow). • Turn off the hydrogen at its source if a power failure occurs.
1 Introduction Safety and Regulatory Certifications The 5975 Series MSD conforms to the following safety standards: • Canadian Standards Association (CSA): CAN/CSA-C222 No.
1 Introduction Symbols Warnings in the manual or on the instrument must be observed during all phases of operation, service, and repair of this instrument. Failure to comply with these precautions violates safety standards of design and the intended use of the instrument. Agilent Technologies assumes no liability for the customer’s failure to comply with these requirements. See accompanying instructions for more information. Indicates a hot surface. Indicates hazardous voltages.
Introduction 1 Electromagnetic compatibility This device complies with the requirements of CISPR 11. Operation is subject to the following two conditions: • This device may not cause harmful interference. • This device must accept any interference received, including interference that may cause undesired operation.
1 Introduction Cleaning/Recycling the Product To clean the unit, disconnect the power and wipe down with a damp, lint-free cloth. For recycling, contact your local Agilent sales office. Moving or Storing the MSD The best way to keep your MSD functioning properly is to keep it pumped down and hot, with carrier gas flow. If you plan to move or store your MSD, a few additional precautions are required. The MSD must remain upright at all times; this requires special caution when moving.
Agilent 5975 Series MSD Troubleshooting and Maintenance Manual 2 General Troubleshooting Troubleshooting Tips and Tricks 30 General Symptoms 31 Chromatographic Symptoms 33 Mass Spectral Symptoms 38 Pressure Symptoms 42 Temperature Symptoms 45 Error Messages 47 Air Leaks 53 Contamination 54 How to identify the symptoms and causes of problems in your MSD. This is a quick reference to symptoms and possible causes of the most common problems experienced by users.
2 General Troubleshooting Troubleshooting Tips and Tricks Rule 1: “Look for what has been changed.” Many problems are introduced accidentally by human actions. Every time any system is disturbed, there is a chance of introducing a new problem. • If the MSD was just pumped down after maintenance, suspect air leaks or incorrect assembly. • If carrier gas or helium gas purifier were just changed, suspect leaks or contaminated or incorrect gas.
General Troubleshooting 2 General Symptoms This section describes symptoms you might observe when first turning on the GC/MSD system. All of these symptoms would prevent operation of the system. GC does not turn on Nothing happens when the GC is switched on. The GC fans do not turn on and the keypad display does not light.
2 General Troubleshooting MSD turns on but then the foreline pump shuts off MSDs will shut down both the foreline pump and the high vacuum pump if the system fails to pump down correctly. This is usually because of a large air leak: either the sideplate has not sealed correctly or the vent valve is still open. This feature helps prevent the foreline pump from sucking air through the system, which can damage the analyzer and pump. See “Pumpdown failure shutdown” on page 174.
2 General Troubleshooting Chromatographic Symptoms These are symptoms you may observe in the chromatograms generated by data acquisition. In general, these symptoms do not prevent you from operating your GC/MSD system. They indicate, however, that the data you are acquiring may not be the best data obtainable. These symptoms can be caused by instrument malfunctions but are more likely caused by incorrect chromatographic technique.
2 General Troubleshooting • Calibration valve is not working correctly • Bad signal cable connection • Filament has failed or is not connected correctly • Bad ion source wiring connection • Bad detector wiring connection • Failed electron multiplier horn Peaks are tailing • Active sites in the sample path • Injection is too large • Incorrect GC inlet temperature • Insufficient column flow • GC/MSD interface temperature is too low • Ion source temperature is too low Peaks are fronting • Column film thick
General Troubleshooting 2 Peaks have split tops • Bad injection technique • Injection is too large Baseline is rising • Column bleed • Other contamination Baseline is high • Column bleed • Other contamination • Electron multiplier voltage is too high Baseline is falling A falling baseline indicates contamination is being swept away. Wait until the baseline reaches an acceptable level.
2 General Troubleshooting Baseline wanders • Insufficient carrier gas supply pressure* • Malfunctioning flow or pressure regulator* • Intermittent leak in the GC inlet* * These could cause a fault condition in the GC that would prevent the GC from operating.
General Troubleshooting 2 Poor sensitivity • Incorrect tuning • Tune file that does not match the type of analysis • Repeller voltage is too low • Incorrect temperatures (oven, GC/MSD interface, ion source, or mass filter) • Incorrect sample concentration • Leaking GC inlet* • Dirty GC inlet • Incorrect split ratio • Purge off time in splitless mode is too short • Excessive pressure in the MSD • Dirty ion source • Air leak • Poor filament operation • Detector (HED electron multiplier) is not working corre
2 General Troubleshooting Mass Spectral Symptoms This section describes symptoms you might observe in mass spectra. Some of these symptoms will appear in the mass spectra of samples. Others you will observe only in a tune report. Some of these symptoms have causes that can be corrected by the operator. Others, however, require service by an Agilent Technologies service representative.
2 General Troubleshooting High abundances at m/z 18, 28, 32, and 44 or at m/z 14 and 16 • System was recently vented (residual air and water) • Air leak. Large peaks at m/z 14 and 16 are symptomatic of especially large leaks. Mass assignments are incorrect Small shape changes at the top of the mass peaks can cause 0.1 m/z shifts in mass assignments. Shifts greater than 0.2 m/z indicate a possible malfunction.
2 General Troubleshooting Relative abundance of m/z 502 is less than 3% Autotune should give an m/z 502 relative abundance greater than 3%. The relative abundance of m/z 502 can, however, vary a great deal depending on column flow, ion source temperature, and other variables. As long as relative abundance is above 3%, the stability of the relative abundance is more important than the absolute value.
2 General Troubleshooting High mass sensitivity is poor This refers to a condition where the absolute abundance at the upper end of the mass range is poor. Absolute abundance should not be confused with the relative abundance (percentage) of m/z 502 to m/z 69. Sensitivity at high masses can be excellent even if the relative abundance of m/z 502 is low.
2 General Troubleshooting Pressure Symptoms This section describes unusual pressure readings and their possible causes. The symptoms in this section are based on typical pressures. At typical column flow rates (0.1 to 2.0 mL/minute), the foreline pressure will be approximately 20 to 100 mTorr. The analyzer chamber pressure will be approximately 1 × 10-6 to 1.4 × 10-4 Torr.
General Troubleshooting 2 Foreline pressure is too low If the pressures you observe are below 20 mTorr, check for the following: • Column (carrier gas) flow is too low • Column plugged or crushed by an overtightened nut • Empty or insufficient carrier gas supply* • Bent or pinched carrier gas tubing* • Foreline gauge is not working correctly * These could create a fault condition in the GC that would prevent the GC from operating.
2 General Troubleshooting Power indicator on the gauge controller does not light • Unplugged gauge controller power cord • Incorrect or inadequate line voltage (24 V supply) • Failed gauge controller fuse 44 5975 Series MSD Troubleshooting and Maintenance Manual
2 General Troubleshooting Temperature Symptoms The MSD has three heated zones: • Ion source (Source in the MSD ChemStation software) • Mass filter (Quad in the MSD ChemStation software) • GC/MSD interface (in the MSD ChemStation software Thermal Aux #2 for the Agilent 7890A and 6890, Thermal Aux #1 for the Agilent 7820A, Thermal Aux for the Agilent 6850) Each heated zone has a heater and temperature sensor. The ion source and mass filter are powered and controlled by the MSD.
2 General Troubleshooting • Mass filter heater failed (burned out or shorted to ground)* • Mass filter temperature sensor failed* • Source power cable is not connected to the sideboard* • MSD electronics are not working correctly * These will cause an error message.
2 General Troubleshooting Error Messages Sometimes, a problem in your MSD will cause an error message to appear in the MSD ChemStation software. Some error messages appear only during tuning. Other messages may appear during tuning or data acquisition. Some error messages are “latched.” These messages remain active in your data system even if the condition that caused the message has corrected itself.
2 General Troubleshooting Difficulty with the HED supply The only time this error occurs is if the output of the supply cannot get to its destination (the HED). • Large peak, such as the solvent peak, eluted while the analyzer was on • Pressure in the analyzer chamber is too high • Detector is not working correctly • MSD electronics are not working correctly Difficulty with the high vacuum pump In an MSD equipped with a diffusion pump, this indicates the diffusion pump became too hot.
General Troubleshooting 2 High foreline pressure • Excessive carrier gas flow (typically > 5 mL/min) • Excessive solvent volume injected • Large vacuum leak • Severely degraded foreline pump oil (standard foreline pump) • Collapsed or kinked foreline hose • Foreline pump is not working correctly • Foreline gauge is not working correctly (diffusion pump MSD only) Internal MS communication fault • MSD electronics are not working correctly Lens supply fault • Electrical short in the analyzer • MSD electron
2 General Troubleshooting • Electrical leads to the detector are not connected correctly • HED power supply output cable failed • Electrical leads to the ion source are not connected correctly • Filament shorted to the source body Temperature control disabled • One of the heater fuses has failed • MSD electronics are not working correctly Temperature control fault This indicates that something has gone wrong with the temperature control of either the ion source or mass filter (quad) heater.
General Troubleshooting 2 The high vacuum pump is not ready • Diffusion pump is on but has not had enough time (10-15 minutes) to reach its normal operating temperature • Turbo pump is on but has not had enough time (5 minutes) to reach 80% of its normal operating speed • Level of fluid in the diffusion pump is too high • Diffusion pump stack is not aligned correctly • Turbo pump is not working correctly • MSD electronics are not working correctly The system is in standby This message is triggered by a s
2 General Troubleshooting There is no emission current • Filament is not connected properly; try the other filament • Filament has failed; try the other filament • MSD electronics are not working correctly There is not enough signal to begin tune • Corrupted tune file • Poor mass axis calibration • Amu gain or offset is too high • Calibration vial(s) empty or almost empty • Excessive pressure in the analyzer chamber • Air leak • Electron multiplier voltage is too low • Signal cable is not connected • Ele
2 General Troubleshooting Air Leaks Air leaks are a problem for any instrument that requires a vacuum to operate. Leaks are generally caused by vacuum seals that are damaged or not fastened correctly.
2 General Troubleshooting Contamination Contamination is usually identified by excessive background in the mass spectra. It can come from the GC or from the MSD. The source of the contamination can sometimes be determined by identifying the contaminants. Some contaminants are much more likely to originate in the GC. Others are more likely to originate in the MSD.
General Troubleshooting Table 5 2 Common contaminants Ions (m/z) Compound Possible source 18, 28, 32, 44 or 14, 16 H20, N2, O2, CO2 or N, O Residual air and water, air leaks, outgassing from Vespel ferrules 31, 51, 69, 100, 119, 131, 169, 181, 214, 219, 264, 376, 414, 426, 464, 502, 576, 614 PFTBA and related ions PFTBA (tuning compound) 31 Methanol Cleaning solvent 43, 58 Acetone Cleaning solvent 78 Benzene Cleaning solvent 91, 92 Toluene or xylene Cleaning solvent 105, 106 Xylene
2 56 General Troubleshooting 5975 Series MSD Troubleshooting and Maintenance Manual
Agilent 5975 Series MSD Troubleshooting and Maintenance Manual 3 CI Troubleshooting Common CI-Specific Problems 58 Troubleshooting Tips and Tricks 59 Air Leaks 60 Pressure-Related Symptoms 64 Signal-Related Symptoms 68 Tuning-Related Symptoms 77 This chapter outlines the troubleshooting of 5975 Series MSDs equipped with the chemical ionization (CI) source. Most of the troubleshooting information in the previous chapter also applies to CI MSDs.
3 CI Troubleshooting Common CI-Specific Problems Because of the added complexity of the parts required for CI, there are many potential problems added. By far the greatest number and most serious problems with CI are associated with leaks or contamination in the reagent gas introduction system. NCI is especially sensitive to the presence of air; leaks small enough to cause no problems in PCI can destroy NCI sensitivity.
3 CI Troubleshooting Troubleshooting Tips and Tricks Rule 1: “Look for what has been changed.” Many problems are introduced accidentally by human actions. Every time any system is disturbed, there is a chance of introducing a new problem. • If the MSD was just pumped down after maintenance, suspect air leaks or incorrect assembly. • If the reagent gas bottle or gas purifier were just changed, suspect leaks or contaminated or incorrect gas.
3 CI Troubleshooting Air Leaks How do I know if I have an air leak? Large air leaks can be detected by vacuum symptoms: loud gurgling noise from the foreline pump, inability of the turbo pump to reach 95% speed, or, in the case of smaller leaks, high pressure readings on the high vacuum gauge controller.
CI Troubleshooting 3 There should not be any peak visible at m/z 32 (O2). This almost always indicates an air leak. Figure 2 Looking for air leaks Special NCI notes Since NCI is so extremely sensitive, air leaks that are not detectable in EI or PCI can cause sensitivity problems in NCI. To check for this kind of air leak in NCI, inject OFN. The base peak should be at m/z 272. If the abundance of m/z 238 is much greater than that of m/z 272, you have an air leak.
3 CI Troubleshooting • If you just replaced the reagent gas bottle or gas purifier, check the fittings you just opened and refastened. CA U T I O N 3 Check for tightness of seals at GC inlet and interface column nuts. Ferrules for capillary columns often loosen after several heat cycles. Do not overtighten the interface nut. 4 If any of the fittings inside the flow module (VCR fittings) were loosened and then retightened, the gasket must be replaced. These gaskets are good for one use only.
CI Troubleshooting 3 CI ion source Gas A (methane) supply Gas A select valve Mass flow controller Shutoff valve Gas B (other gas) supply Gas B select valve Calibration valve Restrictor GC/MSD interface Calibration vial GC column Figure 3 Table 6 Schematic of CI flow control module Flow module valve state diagram Result Gas A flow Gas B flow Purge with Gas A Purge with Gas B Pump out flow module Standby, vented, or EI mode Gas A Open Closed Open Closed Closed Closed Gas B Closed Op
3 CI Troubleshooting Pressure-Related Symptoms The following symptoms are all related to high vacuum pressure. Each symptom is discussed in more detail in the following pages. The mass flow controller is calibrated for methane and the high vacuum gauge controller is calibrated for nitrogen, so these measurements are not accurate in absolute terms (Table 7). They are intended as a guide to typical observed readings.
CI Troubleshooting 3 Poor vacuum without reagent gas flow Excess water in the background Scan from 10 to 40 m/z. A large peak at m/z 19 (>m/z 17) indicates water in the background. If water is present, allow the instrument to bake out more and flow reagent gas through the lines to purge any accumulated water. Air leak Run Methane Pretune. See the Operation Manual. A visible peak at m/z 32 indicates air in the system. Check for and correct any leaks. See the Leaks section at the beginning of this chapter.
3 CI Troubleshooting High pressure with reagent gas flow The reagent gas flow rate is too high On the flow controller, turn down reagent gas flow as appropriate. Verify that reagent ion ratios are correct. Air leak Run Methane Pretune. See the Operation Manual. Visible peak at m/z 32 indicates air in the system. Check for and correct any leaks. See the Leaks section at the beginning of this chapter. Interface tip seal is not installed Check the source storage box.
CI Troubleshooting 3 Pressure does not change when reagent flow is changed The reagent gas regulator is closed Check and, if necessary, open the reagent gas regulator. The reagent gas regulator is set to the wrong pressure Set the reagent gas regulator to 10 psi (70 kPa) for methane or to 3 to 10 psi (20 to 70 kPa) for isobutane or ammonia. The valve on the reagent gas bottle is closed Check and, if necessary, open the valve on the reagent gas bottle.
3 CI Troubleshooting Signal-Related Symptoms This section describes symptoms related to the signal. The symptom may be too much signal, too little signal, a noisy signal, or an incorrect signal. Signal-related symptoms are generally observed during tuning but may also be observed during data acquisition. Error messages in autotune due to insufficient signal may vary. The following symptoms are covered in more detail in this section: • No peaks. See page 69. • No or low reagent gas signal. See page 71.
3 CI Troubleshooting No peaks When troubleshooting “no peaks” it is important to specify what mode of operation is being used and what expected peaks are not being seen. Always start with methane PCI and verify presence of reagent ions.
3 CI Troubleshooting No reagent gas peaks in NCI • Reagent gases do not ionize in NCI; look for background ions instead • Verify tune parameters • If no background ions are visible, go back to methane PCI No PFDTD calibrant peaks in NCI • Look for background ions: 17 (OH–), 35 (Cl–), and 235 (ReO3–) • Verify tune parameters • Go back to methane PCI No sample peaks in NCI • Look for background ions: 17 (OH–), 35 (Cl–), and 235 (ReO3–) • Go back to methane PCI • Poor quality reagent gas (purity less than
3 CI Troubleshooting No or low reagent gas signal If you have just installed the CI ion source and have an air leak or large amounts of water in the system and have run one or more autotunes, the ion source is probably dirty now. Fix the air leak. Clean the ion source. Then bake out for two hours before tuning. See the Operation Manual. The wrong reagent gas is flowing. Turn on the correct reagent gas for your tune file. Ion polarity is set to Negative. No reagent gas ions are formed in NCI.
3 CI Troubleshooting The signal cable is not connected. Check and, if necessary, reconnect the signal cable. The filament or filament support is shorted to the ion source body or repeller. Inspect the filament. If necessary, realign the filament support arms. The electron inlet hole is blocked. Inspect the electron inlet hole. If necessary, clean the hole with a clean toothpick and a slurry of aluminum oxide powder and methanol.
3 CI Troubleshooting No or low PFDTD signal, but reagent ions are normal You are using any reagent gas but methane in PCI. Switch to methane. Wrong or corrupted tune file loaded Check your tune file. No PFDTD in the calibrant vial Inspect the calibration vial on the back of the flow controller. If necessary, fill the vial with PFDTD. Do not fill the vial completely; keep the level at least 0.5 cm from the top of the vial. The pressure of the methane entering the flow controller is too high.
3 CI Troubleshooting Excessive noise or low signal-to-noise ratio The GC inlet needs maintenance. Refer to the GC manual. The CI ion source is dirty. Clean the ion source. See “To Clean the CI Ion Source” on page 164 for more information. Poor vacuum Check the pressure on the high vacuum gauge controller. Air leak Run Methane Pretune (in PCI). Large peak at m/z 32 indicates air in the system. Check for and correct any leaks. See the Leaks section at the beginning of this chapter.
CI Troubleshooting 3 Large peak at m/z 19 If the abundance of the peak at m/z 19 is more than half abundance of the peak at m/z 17, then there is probably too much water in the system. The system was not baked out sufficiently after it was last vented. Bake out the system as described in the Maintenance chapter of this manual. Moisture left over in the reagent gas supply tubing and flow module Purge the reagent gas supply lines for at least 60 minutes.
3 CI Troubleshooting Peak at m/z 32 A visible peak at m/z 32 in methane pretune often indicates air in the system. Residual air from recent venting — check for water indicated by a large peak at m/z 19. Bake out the system under vacuum to eliminate water. New or dirty reagent gas supply tubing Purge the reagent gas supply lines and flow module for at least 60 minutes. See the Operation Manual. Air leak Check for leaks and correct any that you find. See “Air Leaks” on page 60.
CI Troubleshooting 3 Tuning-Related Symptoms This section describes symptoms related to tuning. Most symptoms involve difficulties with tuning or with the results of tuning.
3 CI Troubleshooting Reagent gas ion ratio is difficult to adjust or unstable The interface tip seal is incorrectly placed, damaged, or missing. Inspect the interface tip seal. If necessary, remove and reinstall it to ensure a good seal with the CI ion source. Replace it if it is damaged. Install it if it is missing. Residual air and water in the MSD or in the reagent gas supply lines Run the methane pretune. Air will appear as a peak at m/z 32 and excessive water as a peak at m/z 19 > m/z 17.
3 CI Troubleshooting High electron multiplier voltage The electron multiplier voltage can range from a few hundred volts to 3000 V. If the CI autotune program consistently sets the electron multiplier voltage at or above 2600 V but can still find peaks and complete the tune, it may indicate a problem. The filament is worn out. The CI filament may wear out without actually breaking. Check the Electron Energy ramp; the curve should have a definite maximum with an inflection point.
3 CI Troubleshooting Cannot complete Autotune Wrong or corrupted tune file Check the tune parameters. The m/z 28/27 ion ratio (for methane) is incorrect. The correct ratio should be between 1.5 and 5.0. If the ion ratio is incorrect, adjust it. See the Operation Manual. The CI ion source is dirty. Clean the ion source. See “To Clean the CI Ion Source” on page 164 for more information. Too much air or water in the system See “Air Leaks” on page 60. After eliminating these problems, clean the ion source.
CI Troubleshooting 3 Peak widths are unstable Wrong or corrupted tune file Check the tune parameters. The CI ion source is dirty. Clean the ion source. See the “CI Maintenance” chapter of this manual for more information. Air leak Run Methane Pretune (in PCI). A visible peak at m/z 32 indicates air in the system. Check for and correct any leaks. See the “Air Leaks” section at the beginning of this chapter. After eliminating all air leaks, clean the ion source.
3 82 CI Troubleshooting 5975 Series MSD Troubleshooting and Maintenance Manual
Agilent 5975 Series MSD Troubleshooting and Maintenance Manual 4 General Maintenance Before Starting 84 Maintaining the Vacuum System 89 To Remove the MSD Covers 90 To Connect the Micro-Ion Vacuum Gauge 92 To Move or Store the MSD 94 To Check and Add Foreline Pump Oil 96 To Drain the Foreline Pump 98 To Refill the Foreline Pump 100 To Check the Diffusion Pump Fluid 101 To Separate the MSD from the GC 103 To Reconnect the MSD to the 7890A GC/7820A/6890 GC 105 To Reconnect the MSD to the 6850 GC 106 To Refil
4 General Maintenance Before Starting For your safety, read all of the information in this introduction before performing any maintenance tasks. Scheduled maintenance Common maintenance tasks are listed in Table 8. Performing these tasks when scheduled can reduce operating problems, prolong system life, and reduce overall operating costs. Keep a record of system performance (tune reports) and maintenance operations performed.
4 General Maintenance Tools, spare parts, and supplies Some of the required tools, spare parts, and supplies are included in the GC shipping kit, MSD shipping kit, or MSD tool kit. You must supply others yourself. Each maintenance procedure includes a list of the materials required for that procedure. “Consumables and Maintenance Supplies” on page 260 summarizes these.
4 General Maintenance Dangerous temperatures Many parts in the MSD operate at, or reach, temperatures high enough to cause serious burns. These parts include, but are not limited to: • GC/MSD interface • Analyzer parts • Vacuum pumps WARN I NG Never touch these parts while your MSD is on. After the MSD is turned off, give these parts enough time to cool before handling them. WARN I NG The GC/MSD interface heater is powered by a heated zone on the GC.
General Maintenance 4 into a fume hood vented to the outdoors. For the standard foreline pump, this requires removing the oil trap. Be sure to comply with your local air quality regulations. WARN I NG The oil trap supplied with the standard foreline pump stops only foreline pump oil. It does not trap or filter out toxic chemicals. If you are using toxic solvents or analyzing toxic chemicals, remove the oil trap. Do not use the trap if you have a CI MSD.
4 General Maintenance Take extra precautions, such as a grounded antistatic mat, if you must work on components or assemblies that have been removed from the MSD. This includes the analyzer. CA U T I O N To be effective, an antistatic wrist strap must fit snugly (not tight). A loose strap provides little or no protection. Antistatic precautions are not 100% effective. Handle electronic circuit boards as little as possible and then only by the edges.
General Maintenance 4 Maintaining the Vacuum System Periodic maintenance As listed earlier in Table 8, some maintenance tasks for the vacuum system must be performed periodically.
4 General Maintenance To Remove the MSD Covers Materials needed • Screwdriver, Torx T-15 (8710-1622) If you need to remove one of the MSD covers, follow these procedures (Figure 4): NOTE The color of the MSD cover will vary, depending upon the model type, but the installation and removal procedures are the same for all models. To remove the analyzer top cover Remove the five screws and lift the cover off. To remove the left side cover 1 Open the analyzer cover.
General Maintenance 4 Analyzer window cover Latch Analyzer cover Left side cover Figure 4 Removing covers CA U T I O N Do not use excessive force or the plastic tabs that hold the cover to the mainframe will break off.
4 General Maintenance To Connect the Micro-Ion Vacuum Gauge The Micro-Ion vacuum gauge is optional for EI operation. It is required for operating the MSD in CI mode. Materials needed • Micro-Ion vacuum gauge (G3397A) • Power cord • Micro-Ion vacuum gauge cable (G3170-60805) • CI flow module cable-Smart Card to CI flow (G3170-60808) 92 Procedure 1 Use the provided KF-16 clamp to install the Micro-Ion vacuum gauge to the rear of the analyzer chamber. 2 Connect the gauge cables as shown in Figure 5.
General Maintenance CI and upgraded MSDs Figure 5 4 EI only MSDs Micro-Ion vacuum gauge cables 5975 Series MSD Troubleshooting and Maintenance Manual 93
4 General Maintenance To Move or Store the MSD Materials needed • Ferrule, blank (5181-3308) • Interface column nut (05988-20066) • Wrench, open-end, 1/4-inch × 5/16-inch (8710-0510) Procedure CA U T I O N 1 Vent the MSD. 2 Remove the column and install a blank ferrule and interface nut. 3 Tighten the vent valve. 4 Move the MSD away from the GC. 5 Unplug the GC/MSD interface heater cable from the GC. 6 Install the interface nut with the blank ferrule. 7 Open the analyzer cover.
General Maintenance 4 Front thumbscrew Rear thumbscrew Figure 6 Side plate thumbscrews The MSD can now be stored or moved. The foreline pump cannot be disconnected; it must be moved with the MSD. Make sure the MSD remains upright and is never tipped on its side or inverted. CA U T I O N The MSD must remain upright at all times. If you need to ship your MSD to another location, contact your Agilent Technologies service representative for advice about packing and shipping.
4 General Maintenance To Check and Add Foreline Pump Oil Standard foreline pump only Materials needed • Foreline pump oil (6040-0621) • Funnel (9301-6461) • Hex key, 5-mm, to remove drain plug (8710-1838) • Screwdriver, flat-blade, to remove top fill cap Procedure WARN I NG WARN I NG The foreline pump can cause burns if touched when operating. It has a safety shield to prevent the user from touching it. 1 Examine the oil level window (Figure 7). Note the two lines on the pump left of the window.
General Maintenance 5 Reinstall the fill cap. 6 Pump down the MSD.
4 General Maintenance To Drain the Foreline Pump Standard foreline pump only Materials needed • Book or other solid object approximately 5 cm thick • Container for catching old pump oil, 500 mL • Gloves, oil- and solvent-resistant • Screwdriver, flat-blade, large (8730-0002) • Hex key, 5-mm (8710-1838) Procedure WARN I NG The foreline pump can cause burns if touched when operating. It has a safety shield to prevent the user from touching it. 1 Vent the MSD.
4 General Maintenance 6 Replace the drain plug after draining the oil. 7 Refill the foreline pump until the oil level is between the two fill marks in the site window. 8 Replace the fill cap.
4 General Maintenance To Refill the Foreline Pump Standard foreline pump only Materials needed • Foreline pump oil (6040-0621) – approximately 0.28 L required • Funnel (9301-6461) • Gloves, oil- and solvent-resistant • Screwdriver, flat-blade, large (8730-0002) • Drain plug O-ring (if required) (0905-1515) • Hex key, 5-mm (8710-1838) Procedure WARN I NG The foreline pump can cause burns if touched when operating. It has a safety shield to prevent the user from touching it.
4 General Maintenance To Check the Diffusion Pump Fluid Materials needed • Screwdriver, Torx T-15 (8710-1622) Procedure 1 WARN I NG WARN I NG Remove the analyzer window cover. Do not remove any other covers. Removing other covers may expose hazardous voltages. 2 Vent the MSD. 3 Remove the side cover. Keep your hair away from the cooling fan if the MSD is turned on. 4 Check the diffusion pump fluid level. See Figure 8.
4 General Maintenance Fan Fluid level window (sight glass) Figure 8 102 Diffusion pump 5975 Series MSD Troubleshooting and Maintenance Manual
4 General Maintenance To Separate the MSD from the GC Materials needed • Wrench, open-end, 1/4-inch × 5/16-inch (8710-0510) Procedure WARN I NG 1 Vent the MSD. 2 Turn off the GC. Make sure the GC/MSD interface and GC oven have cooled before you remove the column. 3 Remove the capillary column from the GC/MSD interface. 4 The foreline pump may be located on the floor, on the lab bench next to or behind the MSD, or under the analyzer chamber at the back of the MSD.
4 General Maintenance Agilent 7890A GC has a front and a back location for the MSD interface. Agilent 6890 GC has only one (front) location. Agilent 7820A GC has only one location for the MSD interface. Interface cable 5975 Series MSD and Agilent 7890A, 7820A and 6890 GCs 6850 GC has only one location for the MSD interface. The interstitial panel is needed to set the proper distance between the GC and the MSD.
General Maintenance 4 To Reconnect the MSD to the 7890A GC/7820A/6890 GC Materials needed • Wrench, open-end, 1/4-inch × 5/16-inch (8710-0510) Procedure 1 Position the MSD so the end of the GC/MSD interface is near the GC (Figure 9). 2 Reconnect the GC/MSD interface cable. 3 Slide the MSD to its regular position next to the GC. Be careful not to damage the GC/MSD interface as it passes into the GC. Make sure the end of the GC/MSD interface extends into the GC oven.
4 General Maintenance To Reconnect the MSD to the 6850 GC Materials needed • Wrench, open-end, 1/4-inch 5/16-inch (8710-0510) • Screwdriver, Torx T-15 (8710-1622) Procedure 1 Position the MSD so that it is near the GC. 2 If not installed, install the GC/MSD interstitial panel (part number G2589-00031) onto the midsupport and front-support legs of the right side of the MSD. Use three M4 T-15 screws. See Figure 10.
General Maintenance 3 4 Connect the GC and the MSD end of the GC/MSD interface cable. See Figure 11. GC/MSD interface cable, GC end GC/MSD interface cable, MSD end Figure 11 Interstitial panel installed, GC/MSD interface cable connected 4 Carefully push the MSD and GC together.
4 General Maintenance When positioned properly, the end of the GC/MSD interface cover will touch the oven wall and the GC/MSD interface tip will protrude slightly into the GC oven. See Figure 12. Figure 12 108 MSD and 6850 GC properly positioned 5 The foreline pump may be located on the floor, on the lab bench next to or behind the MSD, or under the analyzer chamber at the back of the MSD. Move it as needed to provide slack in the tubing and cables. 6 Reinstall the capillary column.
4 General Maintenance To Refill the EI Calibration Vial Materials needed • PFTBA (05971-60571) Procedure 1 Stop any tuning or data acquisition. 2 Turn off the analyzer. There are several ways to do this: • In the Tune and Vacuum Control view, select MS OFF from the Execute menu. • In the Instrument Control view in the Edit Parameters dialog box, select MS OFF from the Execute menu. 3 If your MSD is equipped with a vacuum gauge, turn off the gauge. 4 Remove the analyzer window cover.
4 General Maintenance 7 Syringe or pipette PFTBA into the vial. With the vial vertical, the liquid should be just below the end of the internal tube, approximately 70 µL of sample. 8 Push the calibration vial into the valve as far as possible. 9 Withdraw the vial 1 mm. This prevents damage when you tighten the collar. 10 Turn the collar clockwise to tighten it. The collar should be snug but not overly tight. Do not use a tool to tighten the collar. It does not require that much force.
4 General Maintenance To Purge the Calibration Valves CA U T I O N After removing a calibrant vial, you must purge the calibration valve. Failure to do so will result in damage to the filaments and the electron multiplier. EI calibration valve After adding new PFTBA to the calibrant vial, you must purge the air out of the vial and valve. 1 If the vacuum gauge controller is on, turn it off. 2 In Tune and Vacuum Control view, select Purge Calibrant Valve under the Vacuum menu.
4 General Maintenance To Remove the EI Calibration and Vent Valve Assembly Materials needed • Screwdriver, Torx T-15 (8710-1622) Procedure CA U T I O N 1 Vent the MSD. 2 Trace the calibration valve cable to the connector next to the fan and disconnect it. 3 Loosen the collar and remove the calibration vial (Figure 13). Just loosen the collar, do not remove it. Removing the valve with the vial installed can result in liquid calibrant getting into the restrictor of the valve.
General Maintenance 4 To Reinstall the EI Calibration and Vent Valve Assembly Materials needed • Calibration valve (G3170-60204) • O-ring for calibration valve (0905-1217) • PFTBA (05971-60571) or other tuning compound • Screwdriver, Torx T-15 (8710-1622) Procedure CA U T I O N 1 Remove the old valve assembly. See page 112 and Figure 13. 2 Be sure the valve O-ring is in place. If it is worn or damaged, replace it.
4 General Maintenance To Replace the Fan for the High Vacuum Pump Materials needed • Fan (G1099-60564) • Screwdriver, Torx T-15 (8710-1622) Procedure WARN I NG WARN I NG 1 Vent the MSD. 2 Remove the left side MSD cover. 3 Disconnect the fan wiring from the connector on the MSD frame (Figure 14). 4 Remove the four fan screws and the safety grill. Remove the fan. Keep the screws. Do not touch the high vacuum pump. The pump could still be hot enough to burn you.
General Maintenance 4 Fan wiring connector Fan wiring Figure 14 Replacing the pump fan (turbo pump shown) 5975 Series MSD Troubleshooting and Maintenance Manual 115
4 General Maintenance To Remove the Micro-Ion Vacuum Gauge Procedure 116 1 Vent the MSD. 2 Disconnect the cable on the back of the Micro-Ion vacuum gauge. 3 Unscrew the red plastic thumbnut on the gauge clamp. 4 Remove the long screw from the clamp. 5 While supporting the gauge body, remove the clamp from the mounting flange. 6 Remove the gauge.
General Maintenance 4 To Reinstall a Micro-Ion Vacuum Gauge Material needed • KF16 O-ring 0905-1463 Procedure 1 Place the KF16 O-ring in the groove on the analyzer chamber flange. Replace it if it is worn or damaged. 2 Hold the gauge flange against the chamber flange with the O-ring. Push the clamp over both flanges. 3 Insert the long screw, add the thumbnut, and tighten. 4 Attach the cable to the back of the gauge.
4 General Maintenance To Lubricate the Side Plate O-Ring Materials needed • Cloths, clean (05980-60051) • Gloves, clean, lint-free • Large (8650-0030) • Small (8650-0029) • Grease, Apiezon L, high vacuum (6040-0289) The side plate O-ring needs a thin coat of grease to ensure a good vacuum seal. If the side plate O-ring appears dry or does not seal correctly, lubricate it using this procedure. A good test is to wipe off the side plate with methanol, then close the analyzer chamber.
General Maintenance 4 Side plate O-ring Figure 15 Side plate O-ring 5975 Series MSD Troubleshooting and Maintenance Manual 119
4 General Maintenance To Lubricate the Vent Valve O-Ring Materials needed • Cloths, clean (05980-60051) • Gloves, clean, lint-free • Large (8650-0030) • Small (8650-0029) • Grease, Apiezon L, high vacuum (6040-0289) • O-ring, vent valve (0905-1217). Replace if the old O-ring is worn or damaged The vent valve O-ring needs a thin coat of lubrication to ensure a good vacuum seal and smooth operation.
General Maintenance 4 Vent valve O-ring Vent valve knob Figure 16 Vent valve O-ring 6 CA U T I O N Reinstall the vent valve knob. Be very careful when reinstalling the vent valve knob. It is possible to cross thread the knob and damage the threads in the valve body. Be sure the O-ring stays in place. 7 Pump down the MSD.
4 General Maintenance To Remove the Diffusion Pump WARN I NG The diffusion pump fluid may contain traces of toxic chemicals. Materials needed • Aluminum foil, clean • Gloves, oil-resistant Procedure 122 1 Vent the MSD. 2 Separate the MSD from the GC. See “To Separate the MSD from the GC” on page 103. 3 Disconnect the foreline gauge assembly from the diffusion pump outlet. The foreline gauge cable can be disconnected or can remain connected to the foreline gauge.
4 General Maintenance 7 Remove the KF50 clamp. See Figure 17. Foreline gauge assembly KF50 clamp O-ring assembly Diffusion pump Diffusion pump outlet Figure 17 Removing the diffusion pump 8 Lower the diffusion pump. 9 Remove the O-ring assembly from the top of the diffusion pump. The O-ring will have diffusion pump fluid on it and will be very sticky. Place the O-ring on clean aluminum foil (shiny side down) to keep your lab bench and the O-ring clean.
4 General Maintenance To Replace the Diffusion Pump Fluid Materials needed • Aluminum foil, clean • Cloths, clean, lint-free (05980-60051) • Container for old diffusion pump fluid • Diffusion pump fluid, 18.5 mL (6040-0809) – 2 required • Gloves • Oil- and solvent-resistant • Thermally insulated Procedure WARN I NG 1 Remove the diffusion pump from the MSD. See page 122. Make sure you remove the O-ring assembly from the top of the diffusion pump.
General Maintenance 4 If the diffusion pump has been heated with insufficient pump fluid (or with a large air leak in the MSD), the remaining pump fluid may be severely charred and blackened. Blackened pump fluid may also be baked onto the internal parts (stack) of the pump. If so, you may have to remove the diffusion pump stack and clean its parts, and the interior of the pump, with methylene chloride. Be very careful when reinstalling the stack.
4 General Maintenance 7 Preheat the new diffusion pump fluid following the instructions on the bottle. 8 Pour new diffusion pump fluid into diffusion pump until the fluid level is within the FULL COLD range. The recommended charge for this pump is 30 mL. It will require approximately 1.5 of the bottles (18.5 mL each) of diffusion pump fluid. Pour the fluid between the center stack and the side wall. Watch the sight glass while pouring. Do not overfill. 9 126 Reinstall the diffusion pump.
4 General Maintenance To Reinstall the Diffusion Pump Materials needed • Gloves, oil-resistant • Vacuum cleaner, non-ESD generating (92175V or equivalent) This procedure works best with two people, one to hold the pump and one to install the clamp. Procedure 1 Vacuum the fan that cools the diffusion pump. Keeping the fan clean helps ensure maximum cooling. This is one of the few times you will have convenient access to the pump side of the fan. 2 Slide the diffusion pump into the MSD.
4 General Maintenance Foreline gauge assembly KF50 clamp O-ring assembly Diffusion pump Diffusion pump outlet Figure 19 128 Reinstalling the diffusion pump 5975 Series MSD Troubleshooting and Maintenance Manual
General Maintenance 4 To Remove the Foreline Gauge Materials needed • Screwdriver, flat-blade, large (8730-0002) Procedure WARN I NG CA U T I O N 1 Vent the MSD. 2 Separate the MSD from the GC. See page 103. The foreline pump and diffusion pump may still be hot. 3 Unplug the foreline gauge cable from the foreline gauge. 4 Disconnect the foreline gauge assembly from the diffusion pump outlet. 5 Loosen the hose clamp.
4 General Maintenance To Reinstall the Foreline Gauge Materials needed • Foreline gauge assembly (G1099-60545) • Screwdriver, flat-blade, large (8730-0002) Procedure 130 1 Connect a new foreline gauge assembly to the foreline hose. 2 Tighten the hose clamp. 3 Reconnect the foreline gauge cable to the foreline gauge. 4 Reconnect the foreline gauge assembly to the diffusion pump outlet. 5 Reconnect the MSD to the GC. See page 105 and page 106 for details.
General Maintenance 4 Maintaining the Analyzer Scheduling None of the analyzer components require periodic maintenance. Some tasks, however, must be performed when MSD behavior indicates they are necessary. These tasks include: • Cleaning the ion source • Replacing filaments • Replacing the electron multiplier horn “General Troubleshooting” on page 29 provides information about symptoms that indicate the need for analyzer maintenance.
4 General Maintenance Some parts can be damaged by electrostatic discharge The wires, contacts, and cables connected to the analyzer components can carry electrostatic discharges (ESD) to the electronics boards to which they are connected. This is especially true of the mass filter (quadrupole) contact wires which can conduct ESD to sensitive components on the side board. ESD damage may not cause immediate failure but will gradually degrade performance and stability. See page 87 for more information.
4 General Maintenance To disassemble the EI ion source Materials needed • Gloves, clean, lint-free • Large (8650-0030) • Small (8650-0029) • Hex ball driver, 1.5 mm (8710-1570) • Hex ball driver, 2.0 mm (8710-1804) • Wrench, open-end, 10 mm (8710-2353) Procedure NOTE 1 Remove the ion source. See the Operation Manual. 2 Remove the filaments (Figure 20). 3 Separate the repeller assembly from the source body. The repeller assembly includes the source heater assembly, repeller, and related parts.
4 General Maintenance Setscrew Source body Repeller Filament Interface socket Repeller insulator Source heater assembly Repeller insulator Washer Repeller nut Filament Lens insulator (1 of 2) Entrance lens Ion focus lens Drawout cylinder Drawout plate Figure 20 134 Disassembling the EI ion source 5975 Series MSD Troubleshooting and Maintenance Manual
General Maintenance 4 To clean the EI ion source Materials needed • Abrasive paper (5061-5896) • Alumina abrasive powder (8660-0791) • Aluminum foil, clean • Cloths, clean (05980-60051) • Cotton swabs (5080-5400) • Glass beakers, 500 mL • Gloves, clean, lint-free • Large (8650-0030) • Small (8650-0029) • Solvents • Acetone, reagent grade • Methanol, reagent grade • Methylene chloride, reagent grade • Ultrasonic bath Preparation 1 Disassemble the ion source. See page 133.
4 General Maintenance CA U T I O N 136 If insulators are dirty, clean them with a cotton swab dampened with reagent-grade methanol. If that does not clean the insulators, replace them. Do not abrasively or ultrasonically clean the insulators.
General Maintenance 4 Source body Repeller Interface socket Drawout plate Drawout cylinder Ion focus lens Entrance lens Figure 21 Source parts to be cleaned 5975 Series MSD Troubleshooting and Maintenance Manual 137
4 General Maintenance Procedure CA U T I O N The filaments, source heater assembly, and insulators cannot be cleaned ultrasonically. Replace these components if major contamination occurs. 3 If the contamination is serious, such as an oil backflow into the analyzer, seriously consider replacing the contaminated parts. 4 Abrasively clean the surfaces that contact the sample or ion beam. Use an abrasive slurry of alumina powder and reagent-grade methanol on a cotton swab.
General Maintenance WARN I NG NOTE 4 Let the parts cool before you handle them. Take care to avoid recontaminating cleaned and dried parts. Put on new, clean gloves before handling the parts. Do not set the cleaned parts on a dirty surface. Set them only on clean, lint-free cloths.
4 General Maintenance To reassemble the EI ion source Materials needed • Gloves, clean, lint-free • Large (8650-0030) • Small (8650-0029) • Hex ball driver, 1.5 mm (8710-1570) • Hex ball driver, 2.0 mm (8710-1804) • Wrench, open-end, 10 mm (8710-2353) Procedure 1 Slide the drawout plate and the drawout cylinder into the source body (Figure 22). 2 Assemble the ion focus lens, entrance lens, and lens insulators. 3 Slide the assembled parts into the source body.
General Maintenance 4 Source body Setscrew Repeller Repeller insulator Filament (1 of 2) Source heater assembly Repeller insulator Washer Repeller nut (do not over-tighten) Interface socket Ion focus lens Drawout cylinder Drawout plate Lens insulator (1 of 2) Entrance lens Figure 22 Assembling the ion source 5975 Series MSD Troubleshooting and Maintenance Manual 141
4 General Maintenance To remove a filament Materials needed • Gloves, clean, lint-free • Large (8650-0030) • Small (8650-0029) • Hex ball driver, 1.5-mm (8710-1570) Procedure WARN I NG 142 1 Vent the MSD. 2 Open the analyzer chamber. 3 Remove the ion source. See the Operation Manual. 4 Remove the filament(s) to be replaced (Figure 23). The analyzer operates at high temperatures. Do not touch any part until you are sure it is cool.
General Maintenance 4 Filament 1 Filament 2 Figure 23 Replacing filaments 5975 Series MSD Troubleshooting and Maintenance Manual 143
4 General Maintenance To reinstall a filament Materials needed • Filament assembly (G2590-60053) • Gloves, clean, lint-free • Large (8650-0030) • Small (8650-0029) • Hex ball driver, 1.5 mm (8710-1570) Procedure 1 Install the new filament (Figure 23). 2 Remove the screw holding the filament to the ion source body. 3 Slide off the filament assembly. 4 Orient the assembly so that the filament is next to the ion source body. 5 Replace the screw to the ion source body.
General Maintenance 4 To remove the heater and sensor from the ion source Materials needed • Gloves, clean, lint-free • Large (8650-0030) • Small (8650-0029) • Hex ball driver, 1.5 mm (8710-1570) • Hex ball driver, 2.0 mm (8710-1804) • Hex nut driver, 5.5 mm (8710-1220) Procedure 1 Vent the MSD. 2 Open the analyzer chamber. 3 Remove the ion source from the source radiator. See the Operation Manual. 4 Remove the filaments. 5 Remove the repeller assembly (Figure 24).
4 General Maintenance Source body Filament Repeller Source heater assembly Repeller insulator Repeller nut, washer, insulator Filament Figure 24 146 Replacing the heater and sensor 5975 Series MSD Troubleshooting and Maintenance Manual
4 General Maintenance To reinstall the heater and sensor in the ion source Materials needed • Gloves, clean, lint-free • Large (8650-0030) • Small (8650-0029) • Hex ball driver, 1.5 mm (8710-1570) • Hex ball driver, 2.0 mm (8710-1804) • Hex nut driver, 5.5 mm (8710-1220) • Source heater assembly (G3169-60177) Procedure CA U T I O N 1 Unpack the new source heater assembly. The heater, temperature sensor, and heater block are already assembled.
4 General Maintenance To remove the heater and sensor from the mass filter Materials needed • Gloves, clean, lint-free • Large (8650-0030) • Small (8650-0029) • Hex ball driver, 1.5 mm (8710-1570) • Hex ball driver, 2.0 mm (8710-1804) Procedure CA U T I O N 148 1 Vent the MSD. 2 Open the analyzer chamber. 3 Disconnect the mass filter heater and temperature sensor wires from the feedthrough board. 4 Remove the mass filter heater assembly from the mass filter radiator.
4 General Maintenance To reinstall the heater and sensor in the mass filter Materials needed • Gloves, clean, lint-free • Large (8650-0030) • Small (8650-0029) • Hex ball driver, 1.5 mm (8710-1570) • Hex ball driver, 2.0 mm (8710-1804) • Mass filter heater assembly (G1099-60172) Procedure CA U T I O N 1 Unpack the new mass filter heater assembly (Figure 25). The heater, temperature sensor, and heater block are already assembled. 2 Install the heater assembly on top of the mass filter radiator.
4 General Maintenance Heater/sensor assembly Mass filter radiator Figure 25 150 Mass filter heater and sensor 5975 Series MSD Troubleshooting and Maintenance Manual
General Maintenance 4 To replace the electron multiplier horn Materials needed • Electron multiplier horn (G3170-80103) • Gloves, clean, lint-free • Large (8650-0030) • Small (8650-0029) Procedure 1 Vent the MSD. 2 Open the analyzer chamber. 3 Open the retaining clip (Figure 26). Lift the arm of the clip up and then swing the clip away from the electron multiplier horn. 4 Remove the electron multiplier horn. 5 Install the new electron multiplier horn. 6 Close the retaining clip.
4 General Maintenance 8 Pump down the MSD.
4 General Maintenance Maintaining the GC/MSD Interface The GC/MSD interface requires no periodic maintenance Rarely, the heater cartridge in the GC/MSD interface fails. In those cases, it is necessary to replace the heater and sensor. This section contains procedures for removing the heater and sensor and installing new ones. See Figure 28.
4 General Maintenance To remove the GC/MSD interface heater and sensor Materials needed • Screwdriver, Torx T-15 (8710-1622) • Hex driver, 1.5 mm (8710-1570) Procedure WARN I NG 1 Vent the MSD. 2 Make sure you turn off the GC/MSD interface heater. This heater is controlled and powered by the GC. 3 Separate the MSD from the GC. 4 Remove the cover from the GC/MSD interface. The GC/MSD interface operates a very high temperatures. It is also well insulated.
General Maintenance CA U T I O N 4 Installing a new heater and sensor in a damaged heater sleeve will result in poor performance of the heated zone and could reduce the lifetime of the new parts.
4 General Maintenance To reinstall the GC/MSD interface heater and sensor Materials needed • GC/MSD interface heater assembly (G1099-60107) • Heater sleeve (G1099-20210); replace the old sleeve if it is damaged • Screwdriver, Torx T-15 (8710-1622) • Hex driver, 1.5 mm (8710-1570) Procedure CA U T I O N 156 1 Slide the new heater and temperature sensor into the heater sleeve (Figure 28). 2 Reinstall the setscrew. 3 Slide the heater sleeve onto the GC/MSD interface.
4 General Maintenance Maintaining the Electronics Scheduled maintenance None of the electronic components of the MSD need to be replaced on a regular schedule. None of the electronic components in the MSD need to be adjusted or calibrated on a regular schedule. Avoid unnecessary handling of the MSD electronics. Electronic components Very few of the electronic components are operator serviceable. The primary fuses can be replaced by the operator. The RF coils can be adjusted by the operator.
4 General Maintenance precautions. The wrist strap should be connected to a known good earth ground. If that is not possible, it should be connected to a conductive (metal) part of the assembly being worked on, but not to electronic components, exposed wires or traces, or pins on connectors. Take extra precautions, such as a grounded antistatic mat, if you must work on components or assemblies that have been removed from the MSD. This includes the analyzer.
4 General Maintenance To adjust the quad frequency Materials needed • Screwdriver, flat-blade, large (8730-0002) Procedure 1 Make sure the MSD is at thermal equilibrium. It takes at least 2 hours after all heated zones have reached their setpoints for the MSD to reach thermal equilibrium. 2 WARN I NG Open the analyzer cover. Do not remove any other covers. Dangerous voltages are present under these covers. 3 Make sure the RF cover on the side board is secure and no screws are missing.
4 General Maintenance Side board RF cover Quad frequency adjustment screws Figure 29 Adjusting the quad frequency 8 Repeat steps 4 through 7 for m/z 650. The minimum voltage is typically between 300 and 340 mV. 9 Exit the Set Optimize Quadrupole Frequency program. 10 Select MS OFF from the Execute menu. 11 Close the analyzer cover. 12 Tune the MSD.
4 General Maintenance To replace the primary fuses Materials needed • Fuse, T8 A, 250 V (2110-0969) – 2 required • Screwdriver, flat-blade (8730-0002) The most likely cause of failure of the primary fuses is a problem with the foreline pump. If the primary fuses in your MSD fail, check the foreline pump. Procedure 1 Vent the MSD and unplug the power cord from the electrical outlet.
4 General Maintenance Primary fuses in holders Figure 30 162 Primary fuses (turbo model shown) 6 Repeat steps 3 through 6 for the other fuse. Always replace both fuses. 7 Reconnect the MSD power cord to the electrical outlet. 8 Pump down the MSD.
Agilent 5975 Series MSD Troubleshooting and Maintenance Manual 5 CI Maintenance To Clean the CI Ion Source 164 To Minimize Foreline Pump Damage from Ammonia (Standard Pump) 166 To Replace the Methane/Isobutane Gas Purifier 167 To Clean the Reagent Gas Supply Lines 168 To Refill the CI Calibrant Vial 169 This chapter describes maintenance procedures and requirements that are unique to 5975 Series MSDs equipped with the Chemical Ionization hardware.
5 CI Maintenance To Clean the CI Ion Source The CI ion source has slightly different cleaning requirements than the EI ion source. See the video clip in the 5975 Series MSD User Information DVD. Frequency of cleaning Because the CI ion source operates at much higher pressures than the EI ion source, it will probably require more frequent cleaning than the EI ion source. Cleaning of the source is not a scheduled maintenance procedure.
CI Maintenance 5 CI source radiator Setscrew CI repeller CI repeller washer CI filament CI heater assembly CI dummy filament CI interface tip seal CI ion focus lens CI drawout cylinder CI drawout plate CI lens insulator (1 of 2) Entrance lens Figure 31 Exploded view of the CI ion source 5975 Series MSD Troubleshooting and Maintenance Manual 165
5 CI Maintenance To Minimize Foreline Pump Damage from Ammonia (Standard Pump) Air ballasting for an hour every day removes most of the ammonia from the pump oil. This will greatly increase the life of the pump. CA U T I O N Only perform this procedure if the pump is at normal operating temperature. The water vapor in air can cause condensation of the ammonia at the ballast valve if the pump is cold. Procedure 1 Turn the ballast valve on the foreline pump (Figure 32) until the 1s are aligned.
5 CI Maintenance To Replace the Methane/Isobutane Gas Purifier Materials needed • Methane/Isobutane gas purifier (G1999-80410) • Front ferrule for 1/8-inch tubing (5180-4110) • Rear ferrule for 1/8-inch tubing (5180-4116) • Tubing cutter (8710-1709) The methane/isobutane gas purifier needs to be replaced after four tanks of reagent gas. This frequency may vary depending on purity of the gas and care taken in uncapping and installing the gas purifier.
5 CI Maintenance To Clean the Reagent Gas Supply Lines Materials needed • Clean, dry nitrogen • Heat gun • Tubing cutter (8710-1709) Procedure If the reagent gas lines become contaminated, they can be cleaned. 1 Disconnect the reagent gas tubing from the gas supply, the gas purifier, and the MSD. 2 Cap the gas purifier following the instructions on the label. 3 Connect one end of the tubing to a supply of clean, dry nitrogen and turn on gas flow.
5 CI Maintenance To Refill the CI Calibrant Vial Materials needed • PFDTD calibrant (8500-8510) Procedure CA U T I O N 1 Set the reagent gas flow to Gas Off. 2 Vent the MSD. 3 Remove the capillary column from the GC/MSD interface. 4 Pull the MSD away from the GC to expose the calibration vial and valve. See page 103. 5 Loosen the collar holding the calibration vial in place. Do not remove the collar. 6 Remove the calibrant vial. See Figure 33. Do not rinse the vial with any solvents.
5 CI Maintenance Calibration valve Collar Calibration vial Figure 33 170 CI calibration valve and vial 5975 Series MSD Troubleshooting and Maintenance Manual
Agilent 5975 Series MSD Troubleshooting and Maintenance Manual 6 Vacuum System Overview 172 Vacuum System Components 173 Common Vacuum System Problems 174 Foreline Pump 175 High Vacuum Pump 178 Analyzer Chamber 179 Side Plate 180 Vacuum Seals 182 Face seals 182 KF (NW) seals 182 Compression seals 183 High voltage feedthrough seal 183 Foreline Gauge 184 Diffusion Pump and Fan 185 Turbo Pump and Fan 191 Calibration Valves and Vent Valve 192 Micro-Ion Vacuum Gauge 195 This chapter describes components of the
6 Vacuum System Overview The vacuum system creates the high vacuum (low pressure) required for the MSD to operate. Without the vacuum, the molecular mean free path would be very short and ions would collide with air molecules before they could reach the detector. peration at high pressures also would damage analyzer components. The 5975 Series MSDs use two vacuum pumps to obtain the vacuum levels needed.
Vacuum System 6 Vacuum System Components The parts of the vacuum system are identified in Figure 34. • Foreline (rough) pump • High vacuum pump (diffusion or turbo pump) • Analyzer chamber • Side plate (analyzer door), and front and rear end plates • Vacuum seals • Calibration valve(s) and vent valve • Vacuum control electronics • Vacuum gauges and gauge control electronics Each of these is discussed in more detail in this chapter.
6 Vacuum System Common Vacuum System Problems Air leak symptoms The most common problems associated with any vacuum system are air leaks. Symptoms of air leaks include: • Loud gurgling noise from the foreline pump (very large leak.
6 Vacuum System Foreline Pump The foreline pump (Figure 35) reduces the pressure in the analyzer chamber so the high vacuum pump can operate. It also pumps away the gas load from the high vacuum pump. The foreline pump is connected to the high vacuum pump by a 130-cm hose called the foreline hose.
6 Vacuum System The standard foreline pump is a two-stage rotary-vane pump. An optional dry pump is also available. The pump turns on when the MSD power is turned on. The foreline pump has a built-in antisuckback valve to help prevent backstreaming in the event of a power failure. The foreline pump can be placed under the analyzer chamber at the rear of the MSD (with the exhaust outlet to the rear) or on the floor below the MSD.
6 Vacuum System The oil pan under the foreline pump can be a fire hazard (standard pump) Oily rags, paper towels, and similar absorbents in the oil pan could ignite and damage the pump and other parts of the MSD. WARN I NG Combustible materials (or flammable/non-flammable wicking material) placed under, over, or around the foreline (roughing) pump constitutes a fire hazard. Keep the pan clean, but do not leave absorbent material such as paper towels in it.
6 Vacuum System High Vacuum Pump Diffusion pump system The diffusion pump supports a maximum flow rate into the MSD of 1.5 mL/min. The diffusion pump uses baffling to prevent vapor from migrating into the analyzer chamber. Foreline pressure is monitored by the foreline gauge. The AC board controls the diffusion pump heater. Turbo pump system The 5975 Series MSD can have one of two turbo pumps. Both pumps are referred to as turbo pumps.
6 Vacuum System Analyzer Chamber The analyzer chamber (Figure 36) is where the analyzer operates. The manifold is extruded and machined from an aluminum alloy. Large openings in the side, front, and rear of the analyzer chamber are closed by plates. O-rings provide the seals between the plates and the manifold. Ports in the manifold and the plates provide attachment points for the Micro-Ion vacuum gauge, calibration valve, vent valve, GC/MSD interface, and high vacuum pump.
6 Vacuum System Side Plate The side plate (Figure 37) covers the large opening in the side of the analyzer chamber. It is attached to the manifold with a hinge. The analyzer assembly is attached to the side plate inside the analyzer chamber. The hinge allows the side plate to swing away from the manifold for easy access to the analyzer. Several electrical feedthroughs are built into the side plate. Wires connect the feedthroughs to analyzer components.
Vacuum System 6 EM voltage Signal (detector output) Mass filter (quadrupole) Screws for radiator mounting brackets (2 of 4) Ion source and heater Detector focus High voltage (HED) Figure 37 Side plate feedthroughs 5975 Series MSD Troubleshooting and Maintenance Manual 181
6 Vacuum System Vacuum Seals Vacuum seals are shown in Figure 38. Several types of Viton elastomer O-ring seals are used to prevent air leaks into the analyzer chamber. All these O-rings, and the surfaces to which they seal, must be kept clean and protected from nicks and scratches. A single hair, piece of lint, or scratch can produce a serious vacuum leak. Two of the O-rings are lightly lubricated with Apiezon-L vacuum grease: the side plate O-ring and the vent valve O-ring.
6 Vacuum System Compression seals A compression fitting consists of a threaded fitting on the analyzer chamber and a threaded collar with a ferrule and O-ring. A cylindrical part fits inside the collar. Tightening the collar presses the ferrule, compressing the O-ring around the part. The calibration vials use compression seals. High voltage feedthrough seal The high voltage (HED) feedthrough seal is an O-ring that is compressed against the side plate by a threaded collar.
6 Vacuum System Foreline Gauge The foreline gauge monitors the pressure (vacuum) at the exit of the diffusion pump. The primary function of the foreline gauge is diffusion pump control. When the foreline pump has reduced the pressure in the analyzer chamber to below 300 mTorr (0.3 Torr), the diffusion pump is automatically switched on. If the foreline pressure rises above 400 mTorr (0.4 Torr), the AC board switches off the diffusion pump heater and the analyzer electronics.
6 Vacuum System Diffusion Pump and Fan The diffusion pump in the MSD is an air-cooled vapor diffusion pump with 90 L/s capacity. It mounts with a KF50 fitting to a baffle adapter clamped to the bottom of the analyzer chamber. The diffusion pump has a cylindrical body surrounded by fins to help dissipate heat. Its inlet is open to the interior of the analyzer chamber, through the adapter and baffle. A structure called the stack is located at the center of the pump body.
6 Vacuum System Diffusion pump outlet Foreline gauge assembly KF10/16 seal KF10/16 clamp Foreline gauge cable – part of high vacuum control cable Foreline hose and hose clamp Figure 39 Diffusion pump parts The diffusion pump transports gas by momentum transfer. The heater boils a special fluid (a polyphenyl ether) inside the stack. As the vapor pressure increases, the pump fluid vapor is forced out and downward through nozzles in the stack.
6 Vacuum System A cooling fan is located between the diffusion pump and the front cover of the MSD. The fan draws air through the cover and blows it over the pump. Without this cooling, the pump fluid vapor would not condense correctly, but would diffuse into the analyzer chamber. The foreline pump is connected by the foreline hose to the outlet of the diffusion pump. It removes the gas molecules that reach the outlet. The diffusion pump operation is controlled by the AC board.
6 Vacuum System Table 10 Diffusion pump thermal switches (continued) Changes at 170 °C rising; 140 °C falling 365 °C rising Function Keeps analyzer turned off until the pump is hot enough to for adequate vacuum. Prevents analyzer damage Shuts off diffusion pump and analyzer if the pump overheats. Prevents damage to the pump and analyzer.
Vacuum System 6 Diffusion pump outlet Inlet Cooling fins Too hot sensor Too cold sensor Fluid level window Diffusion pump heater cable Cold fluid level marker Hot fluid level marker Figure 40 The diffusion pump 5975 Series MSD Troubleshooting and Maintenance Manual 189
6 Vacuum System Diffusion pump fluid that is exposed to air at operating temperature will break down and turn dark brown or black. This reaction is called cracking. Cracked pump fluid gives two symptoms: higher manifold pressure and high background with a large peak at m/z 446. See also • “Maintaining the Vacuum System” on page 89. • The troubleshooting sections of the MSD ChemStation online help.
6 Vacuum System Turbo Pump and Fan The turbo pump is clamped directly to the bottom of the analyzer chamber. The turbo pump has a cylindrical body with its inlet open to the interior of the analyzer chamber. Inside the pump body is a central shaft or cylinder. Sets of small blades (airfoils) radiate from the central shaft. The shaft spins at up to 60,000 revolutions per minute (rpm) in the performance turbo pump, and 90,000 rpm in the standard turbo pump. Turbo pumps move gas by momentum transfer.
6 Vacuum System Calibration Valves and Vent Valve Calibration valves A calibration valve (Figure 41) is an electromechanical valve with a vial to hold the tuning compound. When a calibration valve is opened, tuning compound in the vial diffuses into the ion source. EI MSDs have one calibration valve; CI MSDs have a second calibration valve for the CI tuning compound. The valves are controlled by the MSD ChemStation.
Vacuum System 6 EI CALIBRATION above analyzer window EI calibration vial Vent valve knob EI calibration valve CI CALIBRATION right side of MSD CI calibration valve CI calibration vial Figure 41 Calibration valves 5975 Series MSD Troubleshooting and Maintenance Manual 193
6 Vacuum System Vent valve knob O-ring Air passage Valve closed Figure 42 194 Valve open Valve open too far Vent valve 5975 Series MSD Troubleshooting and Maintenance Manual
6 Vacuum System Micro-Ion Vacuum Gauge The G3397A Micro-Ion vacuum gauge is standard on CI MSDs and optional on EI MSDs. It consists of the sensing element (an ionization-type gauge) and the necessary electronics to support it. Both parts are mounted in a single package. The ionization gauge creates a current when energized electrons collide with gas molecules. The electronics provide the voltages required, measure the current produced, and produce an output signal that is used by the MSD software.
6 196 Vacuum System 5975 Series MSD Troubleshooting and Maintenance Manual
Agilent 5975 Series MSD Troubleshooting and Maintenance Manual 7 Analyzer Overview 198 EI Ion Source 200 CI Ion Source 202 Filaments 204 Filament selection 204 Emission current 204 Electron energy 204 Filament care 205 Other Source Elements 206 Magnet 206 Repeller 206 Drawout plate and cylinder 206 Ion focus 206 Entrance lens 207 Quadrupole Mass Filter 208 AMU gain 209 AMU offset 209 219 width 209 DC polarity 210 Mass (axis) gain 210 Mass (axis) offset 210 Quadrupole maintenance 210 Detector 211 Detector i
7 Analyzer Overview The analyzer (Figure 43) is the heart of the MSD. It ionizes the sample, filters the ions, and detects them. The sample components exiting the GC column flow into the ion source. In the ion source, the sample molecules are ionized and fragmented. The resulting ions are repelled from the ion source into the quadrupole mass filter. The mass filter allows selected ions to pass through the filter and strike the detector.
Analyzer 7 Detector Mass filter heater assembly Mass filter contact Feedthrough board Ion source (inside radiator) Mass filter (inside radiator) Mass filter contact cable Figure 43 The analyzer 5975 Series MSD Troubleshooting and Maintenance Manual 199
7 Analyzer EI Ion Source The EI ion source (Figure 44) operates by electron ionization. The sample enters the ion source from the GC/MSD interface. Electrons emitted by a filament enter the ionization chamber, guided by a magnetic field. The high-energy electrons interact with the sample molecules, ionizing and fragmenting them. The positive voltage on the repeller pushes the positive ions into the lens stack, where they pass through several electrostatic lenses.
Analyzer 7 Lens insulation Entrance lens Ion focus lens Drawout cylinder Drawout plate Filament Repeller Figure 44 Ion source structure The CI ion source is similar in design, but critical dimensions are different. Do not interchange parts.
7 Analyzer CI Ion Source The CI ion source (Figure 45 and Figure 46) is similar to the EI source, but only has one part in common with the EI source — the entrance lens. The single CI filament has a straight wire and a reflector. A “dummy” filament provides connections for the other wires. The holes in the ion source (electron-entrance and ion-exit) are very small (0.5 mm), making it possible to pressurize the ionization chamber.
Analyzer 7 Setscrew CI repeller CI repeller insulator CI filament CI ion source heater assembly CI dummy filament CI interface tip seal CI lens insulator (1 of 2) CI ion focus lens CI drawout cylinder CI drawout plate Entrance lens Figure 46 CI ion source exploded view 5975 Series MSD Troubleshooting and Maintenance Manual 203
7 Analyzer Filaments Two filaments (Figure 46) are located on opposite sides of the outside of the EI ion source. The active filament carries an adjustable AC emission current. The emission current heats the filament causing it to emit electrons which ionize the sample molecules. In addition, both filaments have an adjustable DC bias voltage. The bias voltage determines the energy on the electrons, usually –70 eV. The CI ion source has only one filament of a different design from the EI filaments.
7 Analyzer Filament care Like the filaments in incandescent light bulbs, the ion source filaments will eventually burn out. Certain practices will reduce the chance of early failure: • If you have an optional G3397A Micro-Ion vacuum gauge, use it to verify that the system has an adequate vacuum before turning on the analyzer, especially after any maintenance was performed. • If you are controlling your MSD from the Edit Parameters screen, always select MSOff before changing any of the filament parameters.
7 Analyzer Other Source Elements Magnet The field created by the magnet directs the electrons emitted by the filament into and across the ionization chamber. The magnet assembly is a permanent magnet with a charge of 350 gauss in the center of the field. Repeller The repeller (Figure 46) forms one wall of the ionization chamber. A positive charge on the repeller pushes positively-charged ions out of the source through a series of lenses.
Analyzer 7 Entrance lens The entrance lens (Figure 46) is at the entrance to the quadrupole mass filter. This lens minimizes the fringing fields of the quadrupole which discriminate against high-mass ions. There is a permanent +4.4 volt voltage added to the entrance lens. The total voltage applied to the entrance lens is the sum of the entrance lens offset and entrance lens gain and the +4.4 volt permanent offset. Entrance lens voltage = +4.
7 Analyzer Quadrupole Mass Filter The mass filter separates ions according to their mass-to-charge ratio (m/z). At a given time, only ions of a selected mass-to-charge ratio can pass through the filter to the detector. The mass filter in the MSD is a quadrupole (Figure 47). The quadrupole is a fused-silica (quartz) tube coated with a thin layer of gold. The four hyperbolic surfaces create the complex electric fields necessary for mass selection.
7 Analyzer Figure 47 Quadrupole mass filter AMU gain AMU gain (AmuGain) affects the ratio of DC voltage to RF frequency on the mass filter. This controls the widths of the mass peaks. • Higher gain yields narrower peaks. • AMU gain affects peaks at high masses more than peaks at low masses. AMU offset AMU offset (AmuOffs) also affects the ratio of DC voltage to RF frequency on the mass filter. • Higher offset yields narrower peaks. • AMU offset generally affects peak widths equally at all masses.
7 Analyzer DC polarity The DC polarity (DC Pol) parameter selects the orientation of the direct current applied to the quadrupole mass filter. The DC polarity that works best for your MSD is determined at the factory. It is listed on the final test sheet accompanying your MSD. It is also listed on a label on the cover over the RF coils. This cover can be viewed by removing the upper MSD cover. CA U T I O N Using the nonpreferred DC polarity may result in very poor performance.
Analyzer 7 Detector The detector (Figure 48) in the MSD analyzer is a high energy conversion dynode (HED) coupled to an electron multiplier (EM). The detector is located at the exit end of the quadrupole mass filter. It receives the ions that have passed through the mass filter. The detector generates an electronic signal proportional to the number of ions striking it. The detector has three main components: the detector ion focus, the HED and the EM horn.
7 Analyzer As the EM horn ages, the voltage (EMVolts) required increases over time. If the EM voltage must always be set at or near –3000 VDC to complete Autotune, with no other probable cause, it may need to be replaced. Check your tune charts for gradual degradation, which indicates wearing out. Select View Tunes from the Checkout menu in the Instrument Control view to see the tune charts. Sudden changes usually indicate a different type of problem.
Analyzer 7 Analyzer Heaters and Radiators The ion source and mass filter are housed in cylindrical aluminum tubes called radiators (Figure 49). The radiators control the distribution of heat in the analyzer. They also provide electrical shielding for analyzer components. The source heater and temperature sensor are mounted in the source heater block. The mass filter (quad) heater and temperature sensor are mounted on the mass filter radiator.
7 Analyzer Mass filter radiator Mass filter heater assembly Ion source radiator Ion source heater assembly Figure 49 214 Heaters and radiators 5975 Series MSD Troubleshooting and Maintenance Manual
Agilent 5975 Series MSD Troubleshooting and Maintenance Manual 8 Electronics Local Control Panel and Power Switch 217 Side Board 218 Electronics Module 219 LAN/MS Control Card 223 Power Supplies 224 Back Panel and Connectors 225 Interfacing to External Devices 228 The following assemblies make up the MSD electronics: Except for the Back panel and connectors, Status display and power switch, and Interfacing to other devices sections, most of this material is not essential for day-to-day operation of the MS
8 Electronics Cooling fan Log amplifier LAN/MS control card Main board HED power supply Cooling fan Low voltage power supply Toroid transformer AC board Figure 50 216 The electronics module 5975 Series MSD Troubleshooting and Maintenance Manual
Electronics 8 Local Control Panel and Power Switch Local Control Panel (LCP) You can view MSD system status and perform some control functions from the local control panel on the front of the instrument. Functions available through the local control panel include: • Prepare to vent (cool analyzer and turn off high vacuum pump) • Monitor MSD status • Run autotune • Run method • Run sequence • View and set analyzer temperatures See also The G1701EA GC/MSD ChemStation Getting Started manual.
8 Electronics Side Board The side board is mounted on the side plate. It performs these functions: • Provides the 1 MHz reference clock for the RF amplifier. • Generates the RF component of the voltage applied to the quadrupole mass filter according to a signal from the main board. The amplitude of this voltage is proportional to the mass selected. • Generates the DC component of the voltage applied to the quadrupole mass filter. The magnitude of this voltage is proportional to the RF voltage.
8 Electronics Electronics Module Most of the electronics in the MSD are contained in the electronics module. The whole electronics module can be replaced, if necessary, by your Agilent Technologies service representative.
8 Electronics • Supplies and controls the power for the ion source and quadrupole (mass filter) heaters. • Provides 24 VDC power for the cooling fans. Signal amplifier board The signal amplifier board amplifies the output of the detector. It produces an output voltage of 0 to 10 volts DC, proportional to the logarithm of the input current of 3 picoamps to 50 microamps. An analog-to-digital converter converts the amplifier output voltage to digital information.
Electronics 8 Diffusion pump control The power regulator ensures that the diffusion pump heater receives constant power, even if there are fluctuations in the AC line voltage. It measures the voltage across the heater and the current through it, multiplies them together, and compares the result with a standard value. Any discrepancy is applied as an error signal to adjust the power.
8 Electronics Pumpdown failure shutdown The AC board will shut down both the high vacuum and the foreline pump if the system fails to pump down correctly. One condition that triggers shutdown is turbo pump speed below 80% after 7 minutes, or it the foreline pressure is above 300 mTorr after 7 minutes. This is usually because of a large air leak: either the sideplate has not sealed correctly or the vent valve is still open.
8 Electronics LAN/MS Control Card The LAN/MS control card is located to the left of the main board on the electronics panel. The LAN/MS control card has two main functions: • Providing a communication interface between the MSD and the data system. • Providing real-time control of the MSD, freeing the data system for other tasks.
8 Electronics Power Supplies Low voltage (AC-DC) power supply The low voltage power supply is mounted next to the toroid transformer in the electronics module. A universal input power supply, it converts AC line voltage into the DC voltages used by the rest of the electronics.
8 Electronics Back Panel and Connectors The back panel (Figure 52) contains several connectors, the primary fuses, and several status LEDs. Most of these components are part of the AC board or the LAN/MS control card and extend through the back panel. High vacuum control (HIVAC SIGNAL) connector The high vacuum signal connector is on the AC board. See “Turbo pump control” on page 221 and “Diffusion pump control” on page 221.
8 Electronics RS-232 Serial A connector Not currently used. RS-232 Serial B connector The RS-232 Serial B connector goes to the CI flow module or to the Micro-Ion vacuum gauge, depending on the accessories installed on the MSD. It handles data communication between the GC and the MSD. LAN (I/O) connector The LAN cable from the data system is connected to the I/O LAN connector. This cable carries all data communication between the PC and the MSD.
Electronics 8 Remote start High vacuum control High vacuum power Primary fuses LAN Power cord RS-232 Serial B Foreline pump power cord Figure 52 RS-232 Serial A Back panel connections 5975 Series MSD Troubleshooting and Maintenance Manual 227
8 Electronics Interfacing to External Devices Remote control processor The remote control processor on the LAN/MS control card synchronizes start-run signals with GCs and other devices. The functions of the remote control processor are extended to the remote start (Remote) connector (Figure 53) on the back panel of the MSD. The remote start cable connects the GC and the MSD. Remote start signals It is often necessary to communicate with external devices (for example, a purge-and-trap) during a run.
Electronics 8 signal. On receipt of the ready signal, the desorbtion cycle begins. When a specific temperature is reached, the purge-and-trap closes a contact to indicate the run has started. The ready pin on the remote start connector on the GC is held low at all times except when the GC, MSD, and data system are all ready. On system ready, a logic high of 5 VDC is present between that pin and any ground.
8 230 Electronics 5975 Series MSD Troubleshooting and Maintenance Manual
Agilent 5975 Series MSD Troubleshooting and Maintenance Manual 9 Parts To Order Parts 232 Electronics 233 Cables 233 Printed circuit boards 235 Fuses and power switch 237 Local Control Panel 238 Vacuum System 240 O-rings and seals 240 Standard foreline pump and related parts 241 Diffusion pump and related parts 245 Turbo pump and related parts 247 Analyzer 250 EI source 255 Repeller assembly 257 Heater sensor assembly 257 EI GC/MSD Interface 259 Consumables and Maintenance Supplies 260 CI Parts 265 This c
9 Parts To Order Parts To order parts for your MSD, address the order or inquiry to your local Agilent Technologies office. Supply them with the following information: Model and serial number of your MSD, located on a label on the lower left side near the front of the instrument. • Part number(s) of the part(s) needed • Quantity of each part needed Some parts are available as rebuilt assemblies Rebuilt assemblies pass all the same tests and meet all the same specifications as new parts.
Parts 9 Electronics The printed circuit boards in the MSD are available only as complete assemblies. Individual electronic components are not available. This section contains the following parts: cables (Tables 11 and 12), printed circuit boards (Table 13 and Figure 54), and fuses and switches (Table 14).
9 Parts Table 12 Description Part number AC board control cable (AC board to main board) G1099-60422 Chassis ground wire G1099-60433 Local control panel ribbon cable G3170-60830 Electronics module fan cable G1099-60560 Diffusion pump control cable G3170-60437 Fan (high vacuum) cable G1099-60561 Feedthrough board G1099-60425 HED control cable G1099-60430 HED power cable G1099-60431 High Vacuum power extender cable (AC to back panel) G1099-60436 Low voltage power supply input cable (AC
Parts 9 Printed circuit boards Table 13 Printed circuit boards (Figure 54) Description Part number AC board G3170-65006 Fan for electronics module 3160-1038 Snap-on rivets (4) may be required if old ones are broken by the removal process 0361-1341 HED power supply G3170-80017 Bipolar HED power supply G3170-80018 LAN/MS Control Card – SC3+ 05990-65430 Low voltage (AC-DC) power supply 0950-3067 Main board G3170-65010 LogAmp Fast Electronics G3170-65001 Toroid transformer G1099-60229
9 Parts HED power supply Cooling fan Low voltage power supply Toriod transformer AC board Cooling fan Signal amplifier board LAN/MS control card Main board Figure 54 236 Electronics module 5975 Series MSD Troubleshooting and Maintenance Manual
Parts 9 Fuses and power switch Table 14 Fuses and power switches Description Part number Fuse 8A, 250V 2110-0969 Power button 5041-1203 Power switch extender rod G3170-40050 5975 Series MSD Troubleshooting and Maintenance Manual 237
9 Parts Local Control Panel This section lists replaceable parts for the LCP and related covers. See Table 15.
Parts 9 LCP fascia LCP assembly and fascia Figure 55 LCP replacement parts 5975 Series MSD Troubleshooting and Maintenance Manual 239
9 Parts Vacuum System This section lists replacement parts available for the vacuum system. It includes clamps, O-rings and seals (Table 16), standard foreline pump and related components (Table 17 and Figure 56), dry foreline pump and related components (Table 18 and Figure 57), diffusion pump and related components (Table 19 and Figure 58), and turbo pump vacuum system components (Table 20 and Figure 59).
Parts 9 Standard foreline pump and related parts Table 17 Item Standard foreline pump and related parts (Figure 56) Description Part number Foreline hose assembly (hose and internal spring) 05971-60119 • Hose Clamp* used with 05971-60119 1400-3241 1 Standard foreline pump – 120V – Pfeiffer Duo 2.5 G3170-89025 1 Standard foreline pump – 220V – Pfeiffer Duo 2.
9 Parts Table 17 Item Description Part number 6 M6 Acorn Cap Hex nut Qty. 2 0535-0041 7 M4 Internal Star washer Qty.
Parts 9 Safety cage removed for clarity 1 6 4 3 2 5 7 3 Figure 56 Foreline pump and related parts 5975 Series MSD Troubleshooting and Maintenance Manual 243
9 Parts Dry foreline pump and related parts Table 18 Description Part number Foreline hose assembly (hose and internal spring) 05971-60119 • Hose Clamp* used with 05971-60119 1400-3241 Dry foreline pump G3170-80028 Dry foreline pump (exchange) G3170-89028 Foreline pump inlet seal (KF10/16) 0905-1463 KF10/16 Clamp (foreline inlet), Micro-Ion vacuum gauge 0100-1397 KF16 Hose adapter G1099-20531 KF25 Clamp (tp end of hose – not shown) 0100-0549 KF25 Hose adapter (tp end of hose – not shown
Parts 9 Foreline hose assembly Hose clamp Dry pump Figure 57 Dry foreline pump and related parts Diffusion pump and related parts Table 19 Item 1 Diffusion pump MSD vacuum system components (Figure 58) Description Part number Claw clamps for baffle adapter G3170-60590 Diffusion pump 120V G1099-80500 220/240V G1099-80501 Diffusion pump baffle adapter G1099-20021 Diffusion pump baffle adapter O-ring 0905-1443 Diffusion pump control cable G3170-60437 5975 Series MSD Troubleshooting and Ma
9 Parts Table 19 Item 246 Diffusion pump MSD vacuum system components (Figure 58) (continued) Description Part number Diffusion pump packaging cap G3170-40540 2 Fan (for high vacuum pump) 3160-1037 3 Foreline gauge assembly G1099-60545 Foreline gauge seal 0905-1463 KF10/16 clamp (diffusion pump outlet) 0100-1397 KF10/16 seal (diffusion pump outlet) 0905-1463 KF50 clamp 0100-1395 KF50 seal (foreline pump to baffle adapter) 0100-1884 Side plate (includes feedthroughs and thumbscrews)
Parts 9 3 2 1 Figure 58 Diffusion pump and related parts Turbo pump and related parts Table 20 Item 1 Turbo pump MSD vacuum system components (Figure 59) Description Part number Claw clamps for baffle adapter, standard turbo G3170-60590 Clamp for vacuum gauging 0100-1397 Fan (for high vacuum pump) G1099-60564 KF25 clamp (for turbo pump outlet) 0100-0549 5975 Series MSD Troubleshooting and Maintenance Manual 247
9 Parts Table 20 Item Description Part number KF25 O-ring assembly (for turbo pump outlet) 0100-1551 4 Micro-Ion Vacuum Gauge vacuum gauging electronics G3170-80001 2 Performance turbomolecular pump G3170-89062 2 Standard turbomolecular pump G3170-89061 Turbo pump seal with shield 0905-1613 Turbo power supply only G3170-60600 Turbo separate power supply-control wiring harness G3170-60835 Analyzer chamber (manifold) G3170-20560 Manifold EMC gasket G3170-80031 3 5 248 Turbo pump M
Parts 9 5 4 2 1 3 Figure 59 Turbo pump and related parts 5975 Series MSD Troubleshooting and Maintenance Manual 249
9 Parts Analyzer Table 21 and Figure 60 show the analyzer chamber and associated parts.
Parts 3 9 6 2 1 4 5 Figure 60 Analyzer chamber and related parts Table 22 and Figure 61 show the replacement parts for the analyzer. Analyzer screws (Table 23) and the individual ion source parts (Table 24) are listed in the tables that follow.
9 Parts Table 22 Item 4 4 6 3 5 252 Analyzer parts (Figure 61) (continued) Description Part number EI 350 ion source, new Turbo - inert Diffusion - stainless steel G3170-65760 G3170-65750 EI 350 ion source, rebuilt Turbo - inert Diffusion - stainless steel G3170-69760 G3170-69750 Magnet assembly 05971-60160 Low gauss magnet assembly G3163-60560 Mass filter cable kit G3170-60130 Mass filter contacts (4) G1099-60142 Mass filter canted coil support, detector end G3170-20025 Mass filter
Parts 9 7 (under clips) 3 6 5 4 Figure 61 Analyzer parts 5975 Series MSD Troubleshooting and Maintenance Manual 253
9 Parts Table 23 254 Analyzer screws Description Part number Heater/Sensor (quad) setscrew 0515-1446 Ion source thumbscrew G1099-20138 Magnet mounting screws 0515-1046 Screw – magnet bracket to source radiator 0515-1602 Screws – source radiator and detector to quad radiator G3170-20123 Screws – mass filter contact assembly/heater block G3170-20122 Screws – radiator.
Parts 9 EI source Table 24 * EI ion source (Figure 62) Description Part number Ion source, new Turbo - inert Diffusion - stainless steel G3170-65760 G3170-65750 Ion source, rebuilt Turbo - inert Diffusion - stainless steel G3170-69760 G3170-69750 11 Drawout cyclinder G1072-20008 12 Drawout plate – 3 mm Inert G2589-20100 12 Drawout plate - 3 mm Stainless Steel - Standard 05971-20134 12 Drawout plate – 6 mm Inert* G2589-20045 12 Drawout plate - 6 mm Stainless Steel - RTGA G3163-20530
9 Parts 1 2 5 3 4 7 8 3 9 7 10 11 12 Figure 62 256 EI source 5975 Series MSD Troubleshooting and Maintenance Manual
Parts 9 Repeller assembly Table 25 Repeller assembly Description Part number EI 350 Anodized Repeller assembly G3170-60172 Inert EI 350 Anodized Repeller assembly G3170-60171 Insulator (2 required) G1099-20133 Nut, 5.
9 Parts Table 26 258 Heater sensor block assembly Description Part number Heater, Repeller, Japan G3170-60103 High Temp Source Sensor G3170-60104 5975 Series MSD Troubleshooting and Maintenance Manual
Parts 9 EI GC/MSD Interface Table 27 lists the replacement parts related to the EI GC/MSD interface. Table 27 EI GC/MSD interface Description Part number GC/MSD interface (complete) G1099-60300 Interface column nut 05980-20066 Heater sleeve G1099-20210 Heater/Sensor assembly G1099-60107 Insulation G1099-20301 Setscrew for heater/sensor assembly 0515-0236 Screws, M4x0.
9 Parts Consumables and Maintenance Supplies This section (Tables 28 through 31) lists parts available for cleaning and maintaining your MSD. Table 28 260 EI maintenance supplies Description Part number Abrasive paper, 30 µm 5061-5896 Alumina powder, 1 kg 8660-0791 Cloths, clean (qty 300) 05980-60051 Cloths, cleaning (qty 300) 9310-4828 Cotton swabs (qty 100) 5080-5400 Diffusion pump fluid (2 required) 6040-0809 Foreline pump oil, P3, 0.
Parts Table 29 9 Tools Description Part number Column installation tool G1099-20030 Funnel 9301-6461 Hex key, 5 mm 8710-1838 Tool Kit G1099-60566 Ball drivers, 1.5-mm 8710-1570 Ball drivers, 2.0-mm 8710-1804 Ball drivers, 2.5-mm 8710-1681 Hex nut driver, 5.5-mm 8710-1220 Pliers, long-nose (1.5-inch nose) 8710-1094 Screwdrivers Flat-blade, large 8730-0002 Screwdrivers Torx, T-10 8710-1623 Screwdrivers Torx, T-15 8710-1622 Screwdrivers Torx.
9 Parts Table 30 Ferrules Description Part number For the GC/MSD interface • Blank, graphite-vespel 5181-3308 • 0.3-mm id, 85%/15% for 0.10-mm id columns 5062-3507 • 0.4-mm id, 85%/15%, for 0.20 and 0.25-mm id columns 5062-3508 • 0.5-mm id, 85%/15%, for 0.32-mm id columns 5062-3506 • 0.8-mm id, 85%/15%, for 0.53-mm id columns 5062-3538 For the GC inlet 262 • 0.27-mm id, 90%/10%, for 0.10-mm id columns 5062-3518 • 0.37-mm id, 90%/10%, for 0.20-mm id columns 5062-3516 • 0.
Parts Table 31 9 Miscellaneous EI and CI parts and samples Description Part number EM Horn G3170-80103 Filament assembly (EI) G2590-60053 Filament assembly (High temperature EI for GCMS) G3170-60050 Filament assembly (CI) G1099-80053 Foreline pump oil (1 liter), P3 6040-0621 Foreline exhaust oil mist trap G1099-80039 Heater/Sensor GC/MSD interface G1099-60107 Benzophenone, 100 pg/µL 8500-5400 Octafluoronaphthalene, OFN, 1pg/µL 5188-5348 Octafluoronaphthalene, OFN, 100 fg/µL 5188-534
9 Parts Table 31 264 Miscellaneous EI and CI parts and samples (continued) Description Part number Tubing cutter replacement blades 8710-1710 CI shipping kit G3170-60505 5975 Series MSD Troubleshooting and Maintenance Manual
Parts 9 CI Parts Tables 32 through 34 and Figures 63 and 64 show parts that may be required to maintain the 5975 Series MSD with CI. The parts in this section are related directly to the CI accessory; other parts for the MSD can be found in the previous sections of this chapter.
9 Parts Table 32 Item * CI flow control module (Figure 63) (continued) Description Part number Swagelok nut, for 1/8-inch fitting, 20/package 5080-8751 Swagelok nut and ferrules, 20 sets/package 5080-8751 Not set up 5 3 4 1 2 Figure 63 266 CI flow control module 5975 Series MSD Troubleshooting and Maintenance Manual
Parts Table 33 Item CI ion source (Figure 64) Description Part number Box for ion source G1999-65001 350 CI ion source, new G3170-65403 1 CI drawout cylinder G1999-20444 2 CI drawout plate G1999-20446 3 CI filament G1099-80053 4 CI heater block G3170-20431 350 CI repeller block G3170-20133 5 CI interface tip seal G1999-60412 6 CI ion focus lens G1999-20443 7 CI lens insulators (pair) G1999-20445 8 CI repeller G1999-20432 9 CI repeller insulator G1999-20433 10 CI source
9 Parts 15 11 9 8 10 5 3 14 4 12 14 7 13 1 6 2 7 Figure 64 268 Exploded view of the CI ion source 5975 Series MSD Troubleshooting and Maintenance Manual
Parts Table 34 9 CI GC/MSD interface Description Part number CI GC/MSD interface Assembly G3170-65400 Heater clamp G1999-20410 Heater/Sensor assembly G1099-60107 Transfer line cup (cover) G3170-00405 Interface insulation G1999-20401 Screws for heater clamp 0515-0383 Screws to attach interface to manifold 0515-0380 Welded interface G3170-60401 Interface tip seal G1999-60412 5975 Series MSD Troubleshooting and Maintenance Manual 269
9 270 Parts 5975 Series MSD Troubleshooting and Maintenance Manual
Index Numerics 19, large peak at m/z, in CI MSD, 75 219 width, 209 32, visible peak at, in CI MSD, 76 A Abrasively cleaning ion source parts, 138 parts to be cleaned, 135 Abundance absolute, 40 low for m/z 502, 40 relative, 40 AC board, 220 Adjusting the RF coils, 159 Air leaks as a source of contamination, 54 finding in CI, 61 small enough to cause no problems in PCI can destroy NCI sensitivity, 58 visible peak at m/z 32 in CI MSD, 76 Ammonia ballasting of the foreline pump required due to, 166 AMU gain,
Index Detector focus lens, 211 Diffusion pump effect of low fluid level in, 42 error messages related to, 48 Diffusion pump fluid as a source of contamination, 54 Drawout plate and cylinder, 206 Drying cleaned ion source parts, 131 Dummy filament, 202 E EI/CI GC/MSD interface. See CI interface Electronics, 215 to 229 ac board, 220 ac-dc board.
Index HED power supply, 224 High electron multiplier voltage in CI MSD, 79 High energy dynode. See HED High vacuum gauge installing, 117 removing, 116 High vacuum pump difficulty with, 48 not ready, 51 High voltage feedthrough.
Index mass (axis) offset, 210 parameters, 208 radiator, 213 RF voltage, 208 Mass gain, 210 Mass offset, 210 Mass spectra high abundances at m/z 18, 28, 32, and 44 or at m/z 14 and 16, 39 high background, 38 inconsistent peak widths, 39 incorrect mass assignments, 39 isotopes missing or ratios are incorrect, 38 precursors, 39 Mass-to-charge ratio, 208 Methane/isobutane gas purifier replacing, 167 Micro-ion vacuum gauge ignition of hydrogen by, 195 reinstalling, 117 removing, 116 Mist filter, for foreline ex
Index Septum, leaking, 53 Side plate lubricating the O-ring, 118 O-ring, 182 thumbscrews, 180 Signal amplifier board, 220 Signal, not enough to begin tune, 52 Smartcard III. See LAN/MS control card Solvent peak effect if analyzer is on, 47, 48 effect on vacuum gauge, 43 Startup failure of the MSD to, 31 See also Pumpdown Static discharge. See Electrostatic discharge Status display, 217 Storing the MSD, 94 Switch, power.
Index Vacuum seals, 182 Vacuum system, 171 part numbers, 240 turbo pump system overview, 178 Valve CI calibration, 192 Voltages, dangerous, 85 W Water detecting in CI, 75 Wid219 parameter, 209 Wiring, dangerous voltages on, 85 276 5975 Series MSD Troubleshooting and Maintenance Manual
