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Summary of Contents for Agilent Technologies 6890N
- Page 1 Agilent 6890N Gas Chromatograph Troubleshooting Agilent Technologies...
- Page 2 Notices © Agilent Technologies, Inc. 2007 Warranty Safety Notices No part of this manual may be reproduced The material contained in this docu- in any form or by any means (including CAU TI O N ment is provided “as is,” and is sub-...
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Page 3: Table Of Contents
Contents Concepts and General Tasks Concepts How to troubleshoot using this manual The [Status] key Configurable Items to Always Keep Current Column configuration Automatic Liquid Sampler configuration Gas configuration Information to Obtain Before Calling Agilent for Service Hardware Symptoms Plunger Errors Vial Mishandled by ALS Syringe Needle Bends During Injection into Inlet FID Does Not Ignite... - Page 4 Poor Peak Resolution Peak Tailing Peak Boiling Point or Molecular Weight Discrimination Poor For any inlet operating in split mode with any detector For any inlet operating in splitless mode with any detector Sample Decomposition in Inlet/Missing Peaks Peak Fronting Noisy Detector, Including Wander, Drift, and Baseline Spikes Noisy baseline Baseline wander and drift...
- Page 5 Oven Temperature Never Cools Down/Cools Very Slowly Oven Never Heats Up Temperature Never Becomes Ready Cannot Set a Flow or Pressure A Gas Does Not Reach Setpoint Pressure or Flow A Gas Exceeds Pressure Setpoint or Flow The Inlet Pressure or Flow Fluctuates Cannot Maintain a Pressure as Low as the Setpoint on a Split Inlet The Measured Column Flow Does Not Equal the Displayed Flow FID Does Not Ignite...
- Page 6 Measuring NPD flows To Perform the GC Self-Test To Adjust the FID Lit Offset To Verify That the FID Flame Is Lit To Verify FID Ignitor Function During Ignition Sequence To Measure FID Leakage Current To Measure FID Baseline Output To Measure NPD Leakage Current To Verify That the NPD Bead Is Ignited To Verify That the FPD Flame Is Lit...
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Page 7: Concepts And General Tasks
Agilent 6890N Gas Chromatograph Troubleshooting Concepts and General Tasks Concepts 8 Configurable Items to Always Keep Current 9 Information to Obtain Before Calling Agilent for Service 10 Agilent Technologies... -
Page 8: Concepts
Concepts and General Tasks Concepts This manual provides lists of symptoms and corresponding tasks to perform should you experience errors associated with GC hardware or chromatographic output, GC Not Ready messages, and other common issues. Each section describes a problem and provides a bulleted list of possible causes for you to troubleshoot. -
Page 9: Configurable Items To Always Keep Current
Concepts and General Tasks Configurable Items to Always Keep Current Certain configurable items in the GC must always be kept current. Failure to do so will lead to reduced sensitivity, chromatographic errors, and possible safety concerns. Column configuration Reconfigure the GC every time a column is trimmed or changed. Also verify that the data system reflects the correct column type, length, id, and film thickness. -
Page 10: Information To Obtain Before Calling Agilent For Service
Concepts and General Tasks Information to Obtain Before Calling Agilent for Service Gather the following information before contacting Agilent for service: • Symptoms • Problem description • Hardware installed and parameters/configuration when the error occurred (sample, supply gas type, gas flow rates, detectors/inlets installed, and so forth) •... -
Page 11: Hardware Symptoms
Agilent 6890N Gas Chromatograph Troubleshooting Hardware Symptoms Plunger Errors 12 Vial Mishandled by ALS 13 Syringe Needle Bends During Injection into Inlet 14 FID Does Not Ignite 15 FPD Does Not Ignite 18 NPD Adjust Offset Process Fails 19 Agilent Technologies... -
Page 12: Plunger Errors
Hardware Symptoms Plunger Errors If the ALS reports a front or back plunger error, check the following possible causes: • The syringe plunger is sticking or is not securely connected to the plunger carrier. Troubleshooting... -
Page 13: Vial Mishandled By Als
Hardware Symptoms Vial Mishandled by ALS Refer to the 7683B Automatic Liquid Sampler Installation, Operation and Maintenance manual for additional information. When you find a mishandled sample vial, do the following: • Check for folds or wrinkles in the crimp cap, especially near the neck of the sample vial. -
Page 14: Syringe Needle Bends During Injection Into Inlet
Hardware Symptoms Syringe Needle Bends During Injection into Inlet When troubleshooting the injector, keep your hands away from WA RN ING the syringe needle. The needle is sharp and may contain hazardous chemicals. Refer to the 7683B Automatic Liquid Sampler Installation, Operation and Maintenance manual for additional information. -
Page 15: Fid Does Not Ignite
Hardware Symptoms FID Does Not Ignite • Check that the FID ignitor glows during ignition sequence. (See To Verify FID Ignitor Function During Ignition Sequence.) • Verify that the Lit Offset is < 2.0 pA. • Check for a plugged or partially plugged jet. •... -
Page 16: Fid Ignitor Does Not Glow During Ignition Sequence
Hardware Symptoms FID Ignitor Does Not Glow During Ignition Sequence Keep body parts at a safe distance from the FID chimney while WA RN ING performing this task. If using hydrogen, the FID flame will not be visible. Remove the detector top cover. Turn the FID flame On. -
Page 17: Corrosion In Fid Collector And Ignitor Glow Plug
Hardware Symptoms Corrosion in FID Collector and Ignitor Glow Plug Agilent recommends inspecting the collector and ignitor glow plug for corrosion while performing maintenance on the FID. The FID combustion process results in condensation. This condensation, combined with chlorinated solvents or samples, causes corrosion and sensitivity loss. -
Page 18: Fpd Does Not Ignite
Hardware Symptoms FPD Does Not Ignite • Check that the FPD temperature is high enough for ignition (> 150 °C). • Check FPD flow rates and that they match the type of filter installed in the FPD. • Measure the actual detector flows. (See To Measure a Detector Flow.) •... -
Page 19: Npd Adjust Offset Process Fails
Hardware Symptoms NPD Adjust Offset Process Fails • Inspect the jet to see if it is clogged. • Measure the actual detector flows. (See To Measure a Detector Flow.) • Check the condition of the bead. Replace if necessary. • Verify that the flow settings are correct. •... - Page 20 Hardware Symptoms Troubleshooting...
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Page 21: Chromatographic Symptoms
Agilent 6890N Gas Chromatograph Troubleshooting Chromatographic Symptoms Retention Times Not Repeatable 22 Peak Areas Not Repeatable 23 Contamination or Carryover 24 Larger Peaks Than Expected 25 Peaks Not Displayed/No Peaks 26 Baseline Rise During Oven Temperature Program 27 Poor Peak Resolution 28... -
Page 22: Retention Times Not Repeatable
Chromatographic Symptoms Retention Times Not Repeatable • Replace the septum. • Check for leaks in the inlet, liner (as applicable), and column connection. (See “Checking for Leaks” .) • Check for sufficient carrier gas supply pressure. The pressure delivered to the GC must be at least 40 kPa (10 psi) greater than the maximum inlet pressure required at final oven temperature. -
Page 23: Peak Areas Not Repeatable
Chromatographic Symptoms Peak Areas Not Repeatable • Check the ALS syringe operation. (See the Troubleshooting section of the 7683B Automatic Liquid Sampler Installation, Operation and Maintenance manual.) • Replace the syringe. • Check for leaks in the inlet, liner (as applicable), and column connection. -
Page 24: Contamination Or Carryover
Chromatographic Symptoms Contamination or Carryover If your output has contamination or unexpected peaks, do the following: Isolate the source Perform a solvent blank run using a new, pure source of solvent. If the contamination disappears, the problem may be either in the sample or solvent-related. Perform a blank run (remove the syringe from the injector and start a run). -
Page 25: Larger Peaks Than Expected
Chromatographic Symptoms Larger Peaks Than Expected • Check each configured column’s dimensions against the actual column dimensions. (See “Configurable Items to Always Keep Current” .) • Check the autosampler injection volume. • Check the vial caps. • Check configured syringe size. Some syringe sizes are specified at half-capacity. -
Page 26: Peaks Not Displayed/No Peaks
Chromatographic Symptoms Peaks Not Displayed/No Peaks • If using an autosampler: • Ensure that there is sample in the vial. • Verify that the ALS plunger carriage is secured to the syringe plunger. • Check that the syringe is installed correctly and draws sample. -
Page 27: Baseline Rise During Oven Temperature Program
Chromatographic Symptoms Baseline Rise During Oven Temperature Program • Inspect the column for bleed. • Check for leaks/oxygen in carrier gas supply. • Check gas supply oxygen trap indicator or date. • Make solvent blank runs to evaluate baseline without sample. •... -
Page 28: Poor Peak Resolution
Chromatographic Symptoms Poor Peak Resolution • Set column flow to optimum linear velocity. • Install and use deactivated consumable parts in the inlet (for example, a liner). • Perform column maintenance: Bake out contaminants, remove the contaminated length of column near the inlet, and reverse and bake out the column as needed. -
Page 29: Peak Tailing
Chromatographic Symptoms Peak Tailing The figure below shows an example of tailing peaks. When troubleshooting tailing peaks, consider: • Which peaks are tailing? • Are the tailing peaks active compounds, all compounds, or are there trends (such as early eluters or late eluters)? •... -
Page 30: Peak Boiling Point Or Molecular Weight Discrimination Poor
Chromatographic Symptoms Peak Boiling Point or Molecular Weight Discrimination Poor If you have trouble with peak boiling point or molecular weight discrimination (inlet discrimination), do the following: • Check the inlet for contamination. Clean and change the liner if necessary. Replace all inlet consumable parts. See the Maintenance manual. -
Page 31: Sample Decomposition In Inlet/Missing Peaks
Chromatographic Symptoms Sample Decomposition in Inlet/Missing Peaks • Lower the inlet temperature. • Check for air or water in the carrier gas; verify gas purity and functionality of traps. • Verify that the liner is appropriate for the sample being run. •... -
Page 32: Peak Fronting
Chromatographic Symptoms Peak Fronting The figure below shows examples of the three types of peaks: symmetric, fronting, and overloaded. Symmetrical Fronting Overloaded If peak fronting or overloading occurs, try the following: • Verify that the injection volume is appropriate. • Ensure that the column is installed properly. •... -
Page 33: Noisy Detector, Including Wander, Drift, And Baseline Spikes
Chromatographic Symptoms Noisy Detector, Including Wander, Drift, and Baseline Spikes Noise should be measured under “normal” operating conditions, with a column connected and carrier gas on. Noise typically has a high frequency component (electronic in origin) and lower frequency components that are referred to as wander and drift. Wander is random in direction but at a lower frequency than the short-term electronic noise. -
Page 34: Baseline Wander And Drift
Chromatographic Symptoms • To Bakeout Contaminants from the PTV Inlet • To Bakeout Contaminants from the VI Inlet • Verify the purity of carrier and detector gases. • Verify proper reassembly after recent maintenance. • Inspect the detector for contamination. If noise increases gradually to an unacceptable level, check the following possible causes: •... -
Page 35: Figure 1. Cyclic Spiking
Chromatographic Symptoms Figure 1 Cyclic spiking Cyclic spiking can be caused by the following: • An electric motor • Building heating/cooling system • Other electronic interferences in the lab Figure 2 Random spiking • Spikes are isolated baseline disturbances, usually appearing as sudden (and large) upscale movements. -
Page 36: Check For The Correct Jet. Low Peak Area Or Height
Chromatographic Symptoms Low Peak Area or Height Check for the correct jet. • If using an inlet in split mode, check the split ratio. • Check for leaks. (See “Checking for Leaks” .) • Check the inlet for contamination. (See “Contamination or Carryover”... - Page 37 Chromatographic Symptoms • Check that the correct filter is installed and is clean. • Check the flow rates. • Check the makeup gas type. Troubleshooting...
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Page 38: Fid Flame Goes Out During A Run And Attempts To Reignite
Chromatographic Symptoms FID Flame Goes Out During a Run and Attempts to Reignite The following is an example chromatogram showing a flameout from a large solvent peak. 5 min After a flameout, the GC will try to ignite the flame three times. If the FID flame goes out during a run, do the following: •... -
Page 39: Fid Baseline Output Above 20 Pa
Chromatographic Symptoms FID Baseline Output Above 20 pA • Verify the purity of the carrier and detector gas supply. • Inspect the column for column bleed. • Check the gas supply trap indicators/dates and ensure that the traps are not expended. •... -
Page 40: Fpd Flame Goes Out During A Run And Attempts To Reignite
Chromatographic Symptoms FPD Flame Goes Out During a Run and Attempts to Reignite If the flame goes out during a run, do the following: • Check the GC system for leaks, especially at the detector column fitting. (See “Checking for Leaks” .) ≥... -
Page 41: Fpd Output Too High Or Too Low
Chromatographic Symptoms FPD Output Too High or Too Low • Verify that the correct filter is being used. Do not use a phosphorus filter with sulfur-optimized flows or a sulfur filter with phosphorus-optimized flows. • Check the position of the column as installed in the detector. •... -
Page 42: Fpd Low Peak Areas
Chromatographic Symptoms FPD Low Peak Areas • Check the flow settings, then measure the actual detector flows. (See “To Measure a Detector Flow” .) • Perform complete inlet maintenance: Replace all consumable parts and bake out the inlet. • Perform column maintenance: Bake out contaminants, remove the contaminated length of column near the inlet, and reverse and bake out the column as needed. -
Page 43: Fpd Large Peak Width At Half-Height
Chromatographic Symptoms FPD Large Peak Width at Half-Height If the FPD produces peaks that are abnormally wide at half the peak height, do the following: • Check the actual injection volume; reduce if necessary. • Verify that the liner is not reacting with the sample. Troubleshooting... -
Page 44: Fpd Baseline Output High, > 20 Pa
Chromatographic Symptoms FPD Baseline Output High, > 20 pA • Check the supply gas purity. • Check all trap indicators and dates. • Check the detector for contamination. • Check for light leaks at the photomultiplier tube (PMT); tighten the PMT if it is loose. •... -
Page 45: Npd Solvent Quenching
Chromatographic Symptoms NPD Solvent Quenching If the baseline does not recover after a solvent peak, try the following: • Turn hydrogren off/on around the solvent peak. • Use nitrogen as the makeup gas. • Set the total column flow and makeup gas to less than 10 mL/min. -
Page 46: Npd Response Low
Chromatographic Symptoms NPD Response Low • Perform complete inlet maintenance: Replace all consumable parts and bake out the inlet. • Perform column maintenance: Bake out contaminants as needed. Verify correct column installation • A large concentration of solvent has extinguished the hydrogen/air plasma. -
Page 47: Npd Baseline Output > 8 Million
Chromatographic Symptoms NPD Baseline Output > 8 million • The collector is shorted to the detector housing. Disassemble the collector and insulators and reinstall. Troubleshooting... -
Page 48: Npd Adjust Offset Process Not Functioning Properly
Chromatographic Symptoms NPD Adjust Offset Process Not Functioning Properly • Inspect the jet to see if it is clogged. • Measure the actual detector flows. (See To Measure a Detector Flow.) • Check the condition of the bead. Replace if necessary. •... -
Page 49: Npd Low Selectivity
Chromatographic Symptoms NPD Low Selectivity • Verify that the hydrogen flow is correct (< 3 mL/min). • Inspect the bead; it may be defective or expended. • Verify correct bead voltage. • Replace the collector and insulators. Troubleshooting... -
Page 50: Negative Peaks Seen With Tcd
Chromatographic Symptoms Negative Peaks Seen with TCD • Verify that the correct gas type is being used. • Check for a leak in the system, especially at the detector column fitting. (See “Checking for Leaks” .) • Consider sensitivity to analytes. •... -
Page 51: Tcd Baseline Has Dampened Sinusoidal Noise Trailing Peaks (Ringing Baseline)
Chromatographic Symptoms TCD Baseline Has Dampened Sinusoidal Noise Trailing Peaks (Ringing Baseline) Wrong data rate is selected in the data system. For TCD, the data rate should be < 5 Hz. Troubleshooting... -
Page 52: Tcd Peaks Have Negative Dip On Tail
Chromatographic Symptoms TCD Peaks Have Negative Dip on Tail • Check for leaks at the detector column adapter fitting. (See “Checking for Leaks” .) • Upgrade the detector to a passivated filament. Troubleshooting... -
Page 53: Gc Not Ready Symptoms
Agilent 6890N Gas Chromatograph Troubleshooting GC Not Ready Symptoms GC Never Becomes Ready 54 Flow Never Becomes Ready 55 Oven Temperature Never Cools Down/Cools Very Slowly 56 Oven Never Heats Up 57 Temperature Never Becomes Ready 58 Cannot Set a Flow or Pressure 59... -
Page 54: Gc Never Becomes Ready
GC Not Ready Symptoms GC Never Becomes Ready Normally the GC becomes ready after flows and temperatures reach setpoint. If the GC does not become ready after a long period of time: • Press [Status] or a component key (for example, [Front inlet]) to see which setpoints or conditions are not ready. -
Page 55: Flow Never Becomes Ready
GC Not Ready Symptoms Flow Never Becomes Ready If the gas flow never becomes ready, check for the following: • Check the supply gas for sufficient delivery pressure. • Check the configured gas type. The configured gas type must match the actual gas plumbed to the GC. •... -
Page 56: Oven Temperature Never Cools Down/Cools Very Slowly
GC Not Ready Symptoms Oven Temperature Never Cools Down/Cools Very Slowly If the oven does not cool down or cools down very slowly: The exhaust coming from the back of the GC is very hot. Keep WA RN ING hands and face away from the exhaust vent. •... -
Page 57: Oven Never Heats Up
GC Not Ready Symptoms Oven Never Heats Up • Press [Status] to check for errors to report to Agilent. The exhaust coming from the back of the GC is very hot. Keep WA RN ING hands and face away from the exhaust vent. •... -
Page 58: Temperature Never Becomes Ready
GC Not Ready Symptoms Temperature Never Becomes Ready To be considered ready, a temperature must be at setpoint ±1 °C for 30 s. If a temperature never becomes ready, do the following: • Check for a missing insulation cup on an inlet or detector. •... -
Page 59: Cannot Set A Flow Or Pressure
GC Not Ready Symptoms Cannot Set a Flow or Pressure If you cannot set a flow or pressure using the split/splitless, PTV, VI, or cool on-column inlets, do the following: • Check the column mode. • Check that a capillary column is configured to the correct inlet. -
Page 60: A Gas Does Not Reach Setpoint Pressure Or Flow
GC Not Ready Symptoms A Gas Does Not Reach Setpoint Pressure or Flow If an inlet does not reach its pressure setpoint, it will shut down in an amount of time determined by the type of inlet. Do the following: •... -
Page 61: A Gas Exceeds Pressure Setpoint Or Flow
GC Not Ready Symptoms A Gas Exceeds Pressure Setpoint or Flow If a gas exceeds its pressure or flow setpoint, do the following: If using a split/splitless inlet, PTV inlet, or volatiles interface: • Decrease the split ratio. • Replace the split vent filter. •... -
Page 62: The Inlet Pressure Or Flow Fluctuates
GC Not Ready Symptoms The Inlet Pressure or Flow Fluctuates A fluctuation in inlet pressure causes variations in the flow rate and retention times during a run. Do the following: • Check if the gas purifier or gas generator is operating at or near capacity. -
Page 63: Cannot Maintain A Pressure As Low As The Setpoint On A Split Inlet
GC Not Ready Symptoms Cannot Maintain a Pressure as Low as the Setpoint on a Split Inlet If the GC cannot maintain a pressure as low as the setpoint, check for the following: • Consider using a liner designed for split analysis. •... -
Page 64: The Measured Column Flow Does Not Equal The Displayed Flow
GC Not Ready Symptoms The Measured Column Flow Does Not Equal the Displayed Flow If the actual column flow does not match the calculated flow displayed on the GC, do the following: • Verify that the measured flows are corrected to 25 °C and 1 atmosphere. -
Page 65: Fid Does Not Ignite
GC Not Ready Symptoms FID Does Not Ignite • Check that the FID ignitor glows during ignition sequence. (See To Verify FID Ignitor Function During Ignition Sequence.) • Verify that the Lit Offset is < 2.0 pA. • Check for a plugged or partially plugged jet. •... -
Page 66: Fid Ignitor Does Not Glow During Injection Sequence
GC Not Ready Symptoms FID Ignitor Does Not Glow During Injection Sequence Keep body parts at a safe distance from the FID chimney while WA RN ING performing this task. If using hydrogen, the FID flame will not be visible. Remove the detector top cover. -
Page 67: Npd Adjust Offset Process Fails
GC Not Ready Symptoms NPD Adjust Offset Process Fails • Inspect the jet to see if it is clogged. • Measure the actual detector flows. (See To Measure a Detector Flow.) • Check the condition of the bead. Replace if necessary. •... -
Page 68: Fpd Does Not Ignite
GC Not Ready Symptoms FPD Does Not Ignite • Check that the FPD temperature is high enough for ignition (> 150 °C). • Check FPD flow rates and that they match the type of filter installed in the FPD. • Measure the actual detector flows. (See To Measure a Detector Flow.) •... -
Page 69: Shutdown Symptoms
Agilent 6890N Gas Chromatograph Troubleshooting Shutdown Symptoms Column Shutdown 70 Hydrogen Shutdown 71 Thermal Shutdowns 72 Agilent Technologies... -
Page 70: Column Shutdown
Shutdown Symptoms Column Shutdown If a carrier gas (which can include an auxiliary flow module or pneumatics control module) shuts down, the following happens: • The oven turns off to avoid column damage. • The oven flaps in the back of the oven open halfway. •... -
Page 71: Hydrogen Shutdown
Shutdown Symptoms Hydrogen Shutdown Hydrogen gas may be used as a carrier or as fuel for some detectors. When mixed with air, hydrogen can form explosive mixtures. The GC monitors inlet and auxiliary gas streams. If a stream shuts down because it is unable to reach its flow or pressure setpoint and if that stream is configured to use hydrogen, the GC assumes that a leak has occurred and shuts down components to create a safe state. -
Page 72: Thermal Shutdowns
Shutdown Symptoms Thermal Shutdowns A thermal fault means that the oven or another heated zone is not within its allowable temperature range (lower than minimum temperature or higher than maximum temperature. To recover from this state: Fix the cause of the shutdown: •... -
Page 73: Nonfunctional Gc Symptoms
Agilent 6890N Gas Chromatograph Troubleshooting Nonfunctional GC Symptoms GC Does Not Turn On 74 PC Cannot Communicate with GC 75 Agilent Technologies... -
Page 74: Gc Does Not Turn On
Nonfunctional GC Symptoms GC Does Not Turn On If the GC does not turn on: • Check the power cord. • Check the building’s power. • If the problem is at the GC, turn off the GC power. Wait 30 seconds, then turn the on the GC power. Troubleshooting... -
Page 75: Pc Cannot Communicate With Gc
Nonfunctional GC Symptoms PC Cannot Communicate with GC • Run a ping test The MS-DOS ping command verifies communications across a TCP/IP connection. To use it, open the command prompt window. Type ping followed by an IP address. For example, if the IP address is 10.1.1.101, enter ping 10.1.1.101. - Page 76 Nonfunctional GC Symptoms Troubleshooting...
- Page 77 Agilent 6890N Gas Chromatograph Troubleshooting Checking for Leaks Leak Check Tips 78 To Check for External Leaks 79 To Check for GC Leaks 81 Leaks in Capillary Flow (Microfluidic) Fittings 82 Agilent Technologies...
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Page 78: Checking For Leaks
Checking for Leaks Leak Check Tips When checking for leaks, consider the system in two parts: external leak points and GC leak points. • External leak points include the gas cylinder (or gas purifier), regulator and its fittings, supply shutoff valves, and connections to the GC supply fittings. -
Page 79: To Check For External Leaks
Checking for Leaks To Check for External Leaks Check for leaks at these connections: • Gas supply bulkhead fittings • Gas cylinder fitting • Regulator fittings • Traps • Shut-off valves • T-fittings Perform a pressure drop test. Turn off the GC. Set the regulator pressure to 415 kPa (60 psi). - Page 80 Checking for Leaks Fully turn the regulator knob counterclockwise to shut the valve. Wait 5 min. If there is a measurable drop in pressure, there is a leak in the external connections. No drop in pressure indicates that the external connections are not leaking. Troubleshooting...
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Page 81: To Check For Gc Leaks
Checking for Leaks To Check for GC Leaks Check for leaks at these connections: • Inlet septum, septum head, liner, split vent trap, split vent trap line, and purge vent fittings • Column connections to inlets, detectors, valves, splitters, and unions •... -
Page 82: Leaks In Capillary Flow (Microfluidic) Fittings
Checking for Leaks Leaks in Capillary Flow (Microfluidic) Fittings For capillary flow fittings, a leak usually indicates that the fitting has been overtightened. Unless the fitting is obviously loose, do not tighten it further. Instead, remove the connection, trim the column end, and install it again. (See To Attach a Capillary Column Using SilTite Metal Fittings.) Also inspect the plat and connection for a broken column tip. -
Page 83: Troubleshooting Tasks
Agilent 6890N Gas Chromatograph Troubleshooting Troubleshooting Tasks To Measure a Column Flow 84 To Measure a Split Vent or Septum Purge Flow 87 To Measure a Detector Flow 89 To Perform the GC Self-Test 92 To Adjust the FID Lit Offset 93... -
Page 84: To Measure A Column Flow
Troubleshooting Tasks To Measure a Column Flow Measuring FID, TCD, uECD, and FPD column flow The following procedure can be used to measure column flow with an FID, TCD, uECD, and FPD. Hydrogen (H ) is flammable and is an explosion hazard when WA RN ING mixed with air in an enclosed space (for example, a flow meter). -
Page 85: Measuring Npd Column Flow
Troubleshooting Tasks Connect the flowmeter to the flowmeter adapter to measure flow rates. Measuring NPD column flow Gather the following: • NPD flowmeter adapter tool (G1534-60640) Troubleshooting... - Page 86 Troubleshooting Tasks • Flow-measuring insert (19301-60660) • Electronic flowmeter calibrated for the gas and flow rates of concern Set the bead voltage to 0.0 V. Cool the NPD to 100 °C. Remove the bead and store it carefully until re-installation. Insert the NPD flowmeter adapter tool into the NPD collector.
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Page 87: To Measure A Split Vent Or Septum Purge Flow
Troubleshooting Tasks To Measure a Split Vent or Septum Purge Flow Hydrogen (H ) is flammable and is an explosion hazard when WA RN ING mixed with air in an enclosed space (for example, a flow meter). Purge flowmeters with inert gas as needed. Always measure gases individually. - Page 88 Troubleshooting Tasks Troubleshooting...
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Page 89: To Measure A Detector Flow
Troubleshooting Tasks To Measure a Detector Flow Measuring FID, TCD, uECD, and FPD flows Hydrogen (H ) is flammable and is an explosion hazard when WA RN ING mixed with air in an enclosed space (for example, a flow meter). Purge flowmeters with inert gas as needed. -
Page 90: Measuring Npd Flows
Troubleshooting Tasks Connect the flowmeter to the flowmeter adapter and measure flows. Measuring NPD flows Gather the following: • NPD flowmeter adapter tool (G1534-60640) Troubleshooting... - Page 91 Troubleshooting Tasks • Flow-measuring insert (19301-60660) • Electronic flowmeter calibrated for the gas and flow rates of concern Set the bead voltage to 0.0 V. Cool the NPD to 100 °C. Remove the bead and store it carefully until re-installation. Insert the NPD flowmeter adapter tool into the NPD collector.
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Page 92: To Perform The Gc Self-Test
Troubleshooting Tasks To Perform the GC Self-Test Turn the GC off. Wait 1 min, then turn the GC back on. If the main GC status screen appears, the GC has passed the self-test. Troubleshooting... -
Page 93: To Adjust The Fid Lit Offset
Troubleshooting Tasks To Adjust the FID Lit Offset To adjust the FID Lit offset: Press [Config]. Scroll to Front detector or Back detector (wherever the detector is installed) and press [Enter]. Scroll to Lit offset. With the Lit offset line highlighted, enter the new parameter for the detector and press [Enter]. -
Page 94: To Verify That The Fid Flame Is Lit
Troubleshooting Tasks To Verify That the FID Flame Is Lit To verify that the FID flame is lit, hold a mirror or other reflective surface over the collector exhaust. Steady condensation indicates that the flame is lit. Typically the FID output will be between 5.0 and 20.0 pA when lit and <... -
Page 95: To Verify Fid Ignitor Function During Ignition Sequence
Troubleshooting Tasks To Verify FID Ignitor Function During Ignition Sequence Keep body parts at a safe distance from the FID chimney while WA RN ING performing this task. If using hydrogen, the FID flame will not be visible. Remove the detector top cover. Turn the FID flame On. -
Page 96: To Measure Fid Leakage Current
Troubleshooting Tasks To Measure FID Leakage Current Load the analytical method. • Make sure flows are acceptable for ignition. • Heat the detector to operating temperature or to 300 °C. Turn off the FID flame. Verify that the FID electrometer is on. Press [Front Detector] or [Back Detector], then scroll to Output. -
Page 97: To Measure Fid Baseline Output
Troubleshooting Tasks To Measure FID Baseline Output With the column installed, load your checkout method. Set the oven temperature to 35 °C. Press [Front Detector] or [Back Detector], then scroll to Output. When the flame is lit and the GC is ready, verify that the output is stable and <... -
Page 98: To Measure Npd Leakage Current
Troubleshooting Tasks To Measure NPD Leakage Current Load the analytical method. Set the NPD Adjust Offset to Off and the Bead Voltage to 0.00 V. • Leave the NPD at operating temperature. • Leave flows on or off. Press [Front Detector] or [Back Detector], then scroll to Output. Verify that the output (leakage current) is stable and <... -
Page 99: To Verify That The Npd Bead Is Ignited
Troubleshooting Tasks To Verify That the NPD Bead Is Ignited Hot exhaust! Detector exhaust is hot and can cause burns. WA RN ING To verify that the bead is ignited, look through the vent hole on the detector lid to see if the bead is glowing orange. The NPD output is selected by the operator as part of the adjust offset process and generally is between 5.0 and 50.0 pA. -
Page 100: To Verify That The Fpd Flame Is Lit
Troubleshooting Tasks To Verify That the FPD Flame Is Lit To verify that the FPD flame is lit: Remove the rubber drip tube from the detector vent. Hold a mirror or shiny surface near the aluminum exhaust tube. Steady condensation means that the flame is lit. Troubleshooting... -
Page 101: To Adjust The Fpd Lit Offset
Troubleshooting Tasks To Adjust the FPD Lit Offset To adjust the FPD Lit offset: Press [Config]. Scroll to Front detector or Back detector (wherever the detector is installed) and press [Enter]. Scroll to Lit offset. With the Lit offset line highlighted, enter the new parameter for the FPD (typical value is 2.0 pA), and press [Enter]. - Page 102 Troubleshooting Tasks Troubleshooting...