Agilent Technologies G6600-90006 manual Detector Sensitivity, Mdl

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Detector Sensitivity

Detector sensitivity is an indicator reflecting the performance characteristics of a given system, and is a useful tool to determine when Detector maintenance is warranted. Sensitivity is typically reported as a minimum detection limit (MDL) as calculated from the following formula:

MDL

= 0.66 ⋅ ( Am'tN / S) ⋅ (PktoPkNoise)

(Wd1/2ht ) ⋅ (Signal)

Where Am't N/S (amount of nitrogen or sulfur) is the mass of nitrogen or sulfur in picograms that reaches the Detector, PktoPkNoise (peak-to-peak noise) is the measure of the noise (e.g. in mV), Signal is the height of the peak in the same units, and Wd1/2ht is the width of the peak at half height in seconds. The constant 0.66 is used in the calculation assuming the MDL S/N = 3.29.

Before it is released from the factory, each 355 SCD must pass an MDL level of <0.5 pg Sulfur/second and each 255 NCD must pass an MDL level of <3.0 pg Nitrogen/second. The response from individual detection systems may vary by a factor of 2 or 3; however, it is typical for Detectors to perform in the 0.1-0.3 pg S/second range for the 355 SCD and in the 1-2 pg N/second for the 255 NCD when tested at Agilent.

Operation and Maintenance Manual

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Contents Operation and Maintenance Manual Safety Notices WarrantyAcknowledgements Manual Part NumberWA R N I N G EnglishIs not in use Español Français Deutsch Italiano Veiligheidsvoorzieningen niet meer DutchFollowing symbols are used on the equipment Contents Overview InstallationOperation Front Panel Controls and Initial StartupPump Maintenance MaintenanceIndex TroubleshootingOperation and Maintenance Manual Introduction Operation and Maintenance Manual System Description Technical Information 255 NCD SpecificationsTechnical Information 355 SCD Power requirements Physical SpecificationsVoltage Nitrogen Chemiluminescence Detector Theory of OperationSulfur Chemiluminescence Detector Dual Plasma Burner with the 355 SCD Dual Plasma ControllerDual Plasma Burner Description of Major ComponentsCross-Section of the Dual Plasma Burner for the 355 SCD Cross-Section of the Dual Plasma Burner for the 255 NCD Chemiluminescence Reaction Cell and Photomultiplier Tube Ozone Generator355 SCD Left Side 355 SCD Right Side 255 NCD Left Side View Vacuum Pump Pressure TransducerOil Coalescing Filter Chemical TrapFID Adapter Optional NCD Reaction CellNCD Photomultiplier Tube and Cooler Schematic for 355 SCD Schematic for 255 NCD, in Nitrogen Mode Schematic for 255 NCD, in Nitrosamine Mode Operation and Maintenance Manual Installation Overview Selecting a Location Power RequirementsCombustion Gas Requirements Environmental ConsiderationsTwo-stage pressure regulators Venting Gases Unpack and Inspect the Instrument Required Installation ToolsInstalling the Edwards RV5 Pump Oil-Sealed Vacuum Pump Set Up the Vacuum PumpWA R N I N G Ard RV5 Oil-Sealed Vacuum Pump and Associated Traps Front Side RV5 Oil- Sealed Vacuum Pump and Associated Traps Top Setting the Gas Ballast Position RV5 Installing the Welch Dry Piston Vacuum Pump Operation Notes Welch Pump Welch Dry Piston Pump Operation and Maintenance Manual SCD 230 V Unit Rear Panel Diagram Connect the Power CordInstall the Dry Compressed Air or O2 Supply Install the Signal Output Cables Additional information Install the Dual Plasma BurnerDual Plasma Controller Rear Panel Install the Dual Plasma ControllerPacked Columns and Columns with an Outside Diameter 0.8 mm Install Column ConnectionsCapillary Columns Install the Transfer Line Front Panel Controls and Initial Startup Detector Front Panel Controls Power ControlsDisplay Output Controls Signal ControlsDual Plasma Controller Front Panel Dual Plasma Controller ControlsVacuum Test Initial StartupRecorder Test Initial Checkout Detector Interface SetupIgnition Operation Start-Up Procedure Detector Stability and Response Detector OperationColumn Bleed CokingFluctuating Pressures Contaminated GasesTypical Operating Conditions Typical Operating ConditionsExpected Detection Limits for Chromatographic Conditions Detection LimitsComplete Shutdown Instrument Shut-DownDaily Shutdown Special Operating Modes Using the 255 NCD in Nitrosamine ModeOperation and Maintenance Manual Operation and Maintenance Manual Maintenance Operating Life of Components for Edwards RV5 Vacuum Pump Pump MaintenanceCleaning the Detector Changing the Oil Mist Filter RV5 Equipment Reaction Cell CleaningReaction Cell, PMT Housing and PMT Socket WA R N I N G Flow Sensor Calibration MDL Detector SensitivitySCD Proper Ferrule Orientation to the Large Ceramic Tube Orientation of the Double Taper Ferrule Tightening the Heater Swivel Nut Operation and Maintenance Manual NCD Proper Ferrule Orientation to the Large Quartz Tube Burner Assembly Detail Tube Replacement for the SCD Positioning the Upper Tube in the Union Fitting 100 Operation and Maintenance Manual Operation and Maintenance Manual 101 Tube Replacement for the NCD Operation and Maintenance Manual 103 NCD Tube Replacement Detail Troubleshooting Solving Detector Problems Detector Fuse Power ProblemsVacuum Pump Fuse Dual Plasma Controller FusesFuse Positions on the Power Supply Board High Voltage Transformer Ozone Generation ProblemsPlugged Restrictor Lines Response Problems Temperature Reading Problems Troubleshooting Detector Issues Diagnosing General ProblemsDetector gases Troubleshooting Pump Issues Troubleshooting Burner Issues Index Agilent Technologies, Inc