Related Manuals for HP 6890 series
Summary of Contents for HP 6890 series
- Page 1 HP 6890 Series Gas Chromatograph Operating Manual The Flame Photometric Detector Manual Part No. G1535 90100...
- Page 2 HP 6890 Series Gas Chromatograph Operating Manual The Flame Photometric Detector Manual Part No. G1535 90100...
- Page 3 HP 6890 Series Gas Chromatograph Operating Manual The Flame Photometric Detector Manual Part No. G1535 90100...
- Page 4 EHewlett Packard Company Safety Information Important User Information Schallemission 1996 for In Vitro Diagnostic The HP 6890 is an IEC Werden Meß und Testgeräte Applications (International mit ungeschirmten Kabeln All Rights Reserved. Electrotechnical Commission) This is a multipurpose und/oder in offenen Reproduction, adaptation, or Safety Class 1 instrument.
- Page 5 The Flame Photometric Detector The sample burns in a hydrogen rich flame, where some species are reduced and excited. The gas flow moves the excited species to a cooler emission zone above the flame where they decay and emit light. A narrow bandpass filter selects light unique to one species, while a shield prevents intense carbon emission from reaching the photomultiplier tube (PMT).
- Page 6 Linearity Several mechanisms produce sulfur emission. The excited species is diatomic, so that emission intensity is approximately proportional to the square of the sulfur atom concentration. The excited species in the phosphorus mode is monatomic, leading to a linear relationship between emission intensity and atom concentration. Quenching effects Hydrocarbon quenching occurs when a high concentration of carbon diox ide from a hydrocarbon peak is in the flame at the same time as the sulfur...
- Page 7 The phosphorus filter is yellow/green and transmits at 525 nanometers. Fused silica liner The HP 6890 FPD uses an inert fused silica insert liner in the transfer line. This allows fused silica columns up to 530 m ID to run right to the base of the flame, minimizing sample tailing or loss on chemically active sites.
- Page 8 This turns off everything except the detector temperature and makeup gas flow. Column installation Refer to the HP 6890 GC Operating Manual for the details of column installation for all detectors. Special FPD adapters The FPD uses special adapters for capillary columns and inch OD PTFE columns.
- Page 9 3. Position the column so it extends about 153 mm from the end of the ferrule. The optimum height may be higher or lower, depending on sample type and detector flow rates. If the column is too high, it can be exposed to the detector flame.
- Page 10 Changing wavelength filters Install the correct optical filter, depending on the choice of Sulfur or Phosphorus mode. For Sulfur Mode, use the 393 nanometer filter (Part No. 19256-80000). For Phosphorus Mode, use the 525 nanometer filter (Part No. 19256-80010). Place filter here To change the filter: Turn the main power switch located under the left side of the oven WARNING...
- Page 11 Compatibility requirements If a single wavelength FPD is to be used with an HP ChemStation, the ChemStation must have version 4.02 or higher software. If a dual wavelength FPD is to be used with an HP ChemStation, the ChemStation must have version 5.01 or higher software.
- Page 12 PMT, and the ignitor control circuitry. The board mounts in the normal HP 6890 detector electronics board slot(s) on the right side of the mainframe.
- Page 13 Lit offset Lit offset is the expected difference between the FPD output with the flame lit and the output with the flame off. It is used to determine whether an attempted ignition has succeeded and to detect a flame out condition.
- Page 14 Flame ignition sequence When either of the flame ignition methods on the next page is used, the HP 6890 FPD automatically performs this sequence: 1. Turns all detector gases air, hydrogen, makeup off. Carrier remains 2. Sets air flow to 200 mL/min.
- Page 15 Lighting the flame Manual To start the flame ignition sequence: Press [Front Det] or [Back Det] FRONT DET (FPD) Temp H2 flow 50.0 50.0 Air flow 60.0 60.0 Mode:Col+mkup=const Combined flow 15.0 Mkup (N2) 50.0 50.0 Flame Off < Scroll to Flame and press [On] Output Automatic If the FPD output with the flame on falls below the flame off output plus...
- Page 16 Electrometer on/off The Configure Detector control table contains an Electrometer On/Off setpoint. High voltage and signal processing circuits are on. If the photomultiplier tube is exposed to room light with the electrometer on, the tube will be destroyed. High voltage and signal processing circuits are off. In this condition, it is safe to expose the photomultiplier tube to room light.
- Page 17 The dual wavelength FPD This is a single burner module with two PMT housings, one with a sulfur filter and the other with a phosphorus filter. Because the optimum gas flows for these elements are quite different, performance of this detector is necessarily a compromise.
- Page 18 Operating the FPD Use the information in Table 2 when selecting temperatures and flows. We suggest that you begin with the suggested flow rates, then vary each gas to maximize detector response. Optimize hydrogen first, then air, and finally the auxiliary gas. This may require a few iterations. Table 2.
- Page 19 Figure 3. FPD control table Press [Front Det] or [Back Det]. Temperature, _C Hydrogen flow, mL/min FRONT DET (FPD) Air flow, mL/min Temp 250 < H2 flow 50.0 50.0 Turn off for packed columns. Air flow 60.0 60.0 For capillary columns, see Mkup (N2) 50.0 50.0 makeup gas flow mode below.
- Page 20 Procedure: Using the FPD Verify that all detector gases are connected, a column is installed, and the system is free of leaks. Check the oven temperature, inlet temperature, and column flow. Use Figure 3 as a guide when operating the FPD. WARNING Verify that a column is installed or the FPD column fitting is plugged before turning on the air or hydrogen.
- Page 21 Flame ignition problems If the FPD flame won't light or stay lit, check/do the following: 1. Be sure there is a problem. The flame normally does not make any sound when it ignites. Also, the increase in signal offset on the visual display is sometimes only a few counts.
- Page 22 Leak testing Turn off all supply gases. Cap the detector exhaust tube with a ¼ inch Swagelok plug (Part No. 0100-0196) and a 40% graphitized Vespel ferrule (Part No. 0100-1061). When testing the flow system under pressure, do not exceed 210 kpa (30 Caution psig).
- Page 23 Parts identification O ring (4) 3 to 6mm U clamp Base G1535-80510 Gigabore liner/ferrule assembly 19256-60590 Transfer tube 19256-80550 O ring, Kalrez, transfer tube 0905-1101 Lower heater block 19256-20500 Heater/sensor assembly G1535-60620 Nut, brass, ¼ in. 0100-0056 Ferrule, Vespel, ¼ in. ID 0100-1061 Jet cartridge G1535-80500...
- Page 24 20 21 4 places Nut, brass, ¼ in. 0100-0056 Ferrule, Vespel, ¼ in. ID 0100-1061 Glow plug 0854-0141 Spacer, ignitor 19256-20590 O ring, Kalrez, ignitor 0905-1102 Weldment, block 19256-80560 Exit tube assembly 19256-20700 Gasket, head shield 19256-80040 Window, first heat shield 19256-80030 Disk, heat shield 19256-20580...
- Page 25 4 Places Clamp 19256-00090 O ring, silicone, 0.926 in. ID (orange) 0905-0955 Window, second heat shield 19256-80060 O ring, silicone, 1.05 in. ID (orange) 0905-1104 Flange adapter 19256-20510 Flange ring 19256-00200 Screw, M3 x 25 (4 required) 0515-0065 O ring, Viton, 1.239 in. ID (brown) 0905-1100...
- Page 26 Heater/sensor assembly G1535-60610 Filters (not shown) Sulfur mode 19256-80000 Phosphorus mode 19256-80010 Replacement photomultiplier tubes (not shown) PM tube ONLY 19256-80050 PM tube and housing assembly 19256-60510 Pneumatics control module (not shown) G1535-60520 Printed Circuit Board (not shown) G1535-60010 Ignitor Cable Assembly (not shown) G1535-60600 Cover Assembly (6890) (not shown) G1535-80520...
- Page 27 Cleaning/replacing windows, filters, and seals Column bleed and/or effluent can contaminate the first quartz window (heat shield) nearest the detector module. Dust, fingerprints, atmospheric contaminants can dirty both quartz windows, the filter, and/or the photo multiplier tube window. Contamination anywhere along the light path between flame and PMT can reduce detector sensitivity.
- Page 28 5. Note placement and types of seals found on disassembled parts. Seals should be replaced with new parts on reassembly. 6. Inspect the windows: chips, scratches, cracks or fogging in the light path scatter light, reducing sensitivity. Replace windows if necessary. 7.
- Page 29 Cleaning/replacing the jet If a response problem is encountered (sensitivity, noise, selectivity) the FPD jet should be inspected for deposits and, if necessary, cleaned or replaced. To properly service the jet, the detector module should be removed from the instrument, followed by appropriate service: 1.
- Page 30 6. This is also an ideal time to inspect/clean the glow plug (see Flame Ignition Problems"), and inspect/clean the quartz windows (see Cleaning/ Replacing Windows, Filter, Seals"). 7. Use compressed air or nitrogen to blow out loose particles from the jet and/or detector module body.
- Page 31 Replacing the transfer line fused silica liner Occasionally the transfer line fused silica liner between the column and FPD module must be inspected, cleaned, and/or replaced. 1. Turn off power to the gas chromatograph and disconnect the main power cord. Remove the detector covers. 2.
- Page 32 8. Loosen the transfer line nut. Remove the two screws that secure the U clamp to the detector frame. Remove the U clamp and the attached parts from the bottom of the detector. Ignitor cable Transfer line nut Heater/sensor cable assembly Heated block U clamp screws 9.
- Page 33 10. With an open end wrench, unscrew the transfer tube from the detector base. Lift the transfer tube containing the fused silica liner verti cally off the instrument. Remove and inspect the fused silica liner and inch Vespel ferrule by pulling the fused silica liner and ferrule out from the bottom.
- Page 34 Replacing the photomultiplier tube If the PMT is defective (high voltage on and the flame lit: low or no signal and/or high noise not attributed to any other source such as bad cables, light leaks, high temperature, defective signal board, etc.), it must be replaced.
- Page 35 Figure 4. FPD Photomultiplier Tube (PMT) Replacement 5 (hidden) Tube socket 19256-20670 End cap 19256-20710 PMT tube housing 19256-20650 Photomultiplier tube 19256-80050 O ring 0905-1099 Resistor network cable assembly 19256-60580...
- Page 36 Printed on recycled paper. This product is recyclable. Manual Part No. Hewlett Packard Company G1535 90100 Printed in USA 12/96...