Fluke 90100 manual Saving the Fpgf Changes, Aborting the Fpgf Changes

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Operation

Operation Instructions 2

2.4.10.1 Changing Front Panel Gain Factor's From the Measurement Screen

The five FPGF's may be set by adjusting the measurement readings to achieve a set of desired values. Press the MEASURE SELECT button until the desired Measurement screen is displayed. Press the GAIN SELECT button to advance the "X" cursor among the five measurement values. Next use the UP and DOWN buttons to adjust the selected measurement value.

When the measurement values are displayed in the absolute form, see Figure 2-26, pressing the UP or DOWN arrow increments or decrements the selected chamber's FPGF. For example, increasing the left

dose value by 2% will increase the left FPGF by 2%.

Figure 2-26. An Absolute Dose Measurement With the Center Ion Chamber Selected for FPGF Modification

When the measurement values are displayed in the percent-of-center form, see Figure 2-27, and the "X" cursor is pointing at one of the percentage values, pressing the UP or DOWN arrow will increment or decrement the selected chamber's FPGF. For example, increasing the left percentage value by 2% will increase the left FPGF by 2%.

When the measurement values are displayed in the percent-of-center form and the "X" cursor points to the center ion chamber's absolute measurement value, pressing the UP or DOWN arrow increments or decrements all five of the FPGF's. This causes the FPGF of the center channel to increase, while allowing the four peripheral ratios to remain unchanged. For example, increasing the center chamber's

absolute dose value by 2% will increase all five of the FPGF's by 2%.

Figure 2-27. A Percentage Dose Measurement With the Left Ion Chamber Selected for FPGF Modification

2.4.10.3 Saving the FPGF Changes

To save any changes made to the FPGF's, press and hold the GAIN SELECT button for approximately three seconds. These settings become permanent and will be used when the 35360A TRACKER Display displays the FPG annunciator.

2.4.10.4 Aborting the FPGF Changes

To abort any changes made to the FPGF's, turn off the instrument while in the Gain Setting Mode. This causes the 35360A TRACKER Display to discard the new FPGF settings and use the values previously stored.

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Contents Tracker System ModelFluke Biomedical Table of Contents Customization Maintenance and ServiceAppendix a Using Build-Up Theory of OperationIntroduction General InformationModel FeaturesManual Addenda Before You Start Safety PrecautionsSafety Terms SpecificationsIon Chamber Factory Calibration Nominal Ion Chamber CharacteristicsMechanical Specifications Recommended Operation ConditionsElectrometer / A-D Converter Measurements ModeDisplay Mode Model 35360A Tracker DisplayEnvironment High Performance Battery ChargerUnpacking and Inspection Interface Cable Detector to DisplayOptional Equipment Standard System ContentsBlank Rear Panel Familiarization OperationDetector Input Powering the SystemDisplay. Be sure to use the correct end of the cable 3 RS-232 Computer Interface RJ-45 Style Positioning the Model 35300A Detector in the BeamOperation Positioning the Model 353300A Detector in the Beam Front Panel Controls Operation InstructionsUnits Select PowerReset Test/DetectorPowering Up the Model 35360A Tracker Display Powering Down the Model 35360A Tracker DisplayUsing the TEST/DETECTOR Button Test/Detector Screen 2 Ion Chamber Calibration Factors Using the Units Select ButtonUsing the Gain Select Button Normal Mode Using the AIR Density ButtonAbsolute Measurements Using the Measure Select Button Normal ModePercent-of-Center Measurements Underranging and Overranging Conditions Battery and Bias Annunciators24. Positions of the Battery and Bias Annunciators Gain Setting ModeAborting the Fpgf Changes Saving the Fpgf ChangesBlank Theory of Operation Hardware Block Diagram of the Model 35360A Tracker Display Power SupplyVFD Display Front Panel Switches2 300-VOLT Electronic Bias Supply ProcessorSerial Communications Port ElectrometerMultiplexer and A/D Converter Air Density Corrections Model 35300A Ion Chamber DetectorsBasic Operating Equations Basic Operating Quantities Blank Maintenance & Service Problem TroubleshootingNo Display Flowchart Low battery Yes Annuciator displayed? Low Battery Indication at the Display35360A Tracker Bias Error LoBias or HiBias Indication at the DisplayLeakage Flowchart Dose Rate Measurement Zero Problem Flowchart Line Fuse ReplacementIf fuses continue to blow return instrument for repair Interface Connector Cleaning Cleaning the InstrumentReplaceable Parts Information Recalibration & Repair Information / Technical Assistance Replaceable Parts ListCustomization Screen Formats Make a Working DiskConnection to the Computer Starting the Customization SoftwareDisplay Customization Items Screen Appearance F10 Exit F1 Help On-Line Help for using the Customization softwareF2 Edit Item Editing F6 Print Report PrintingDefinitions Ion Chamber Calibration Factor Iccf Setting the Electrometer Gains and OffsetsCharge Gain QG Current Gain, Current Zero IG and ADZElectrometer Charge Gains QG Electrometer Current Gain IGUsage Examples Changing the Power Down IntervalChanging the ION Chamber Calibration Factor Units Input Errors ErrorsBuild-Up, Peg, and Retainer Kit Options Using Build-UpNominal Number of build-up Solid Water Appendix Fluke Biomedical