Fluke manual Powering Up the Model 35040 Therapy Dosimeter

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35040

Operators Manual

and bias voltages, automatic leakage compensation settings, and timer settings.

•When the Test Function screen is displayed, pressing the TEST FUNCTION button displays a cursor that allows modification of the following settings:

-Enabling or disabling automatic leakage compensation or setting of the start and stop exposure current thresholds

-Selecting the timer interval, count mode, and decimal places

-Specifying the effective exposure time presentation

Detector Select

The DETECTOR SELECT button displays the Detector Select screen.

Air Density

The AIR DENSITY button displays the Air Density screen. Subsequent presses advance the cursor through the temperature, pressure, and air density correction on/off fields.

Units Select

The UNITS SELECT button displays the Units Select screen for selecting the rate divisor.

Bias Select

The BIAS SELECT button displays the Bias Select screen.

Reset/Measure

•When the Measurement screen is not displayed, pressing the RESET/MEASURE button displays the Measurement screen and the Measurement display that was last viewed since power-up.

•When the Measurement screen is displayed:

-And when the instrument is performing exposure measurements, pressing the RESET/MEASURE button toggles the timer

-Pressing and holding the RESET/MEASURE button for one second zeroes all exposure measurements; the instrument also zeroes leakage measurements if leakage was being measured

Up (S)

The function of the UP button depends on the screen displayed. It increases the temperature or pressure setting. It toggles the state of the air density correction annunciator. For the Test Function and Measurement screens, it displays the next information screen. It presents the next ion chamber for the Detector Select screens. It increases the dose rate unit’s divisor. For setting the start and stop exposure current thresholds, it increases the setting.

Down (T)

The function of the DOWN button depends on the screen displayed. It decreases the temperature or pressure setting. It toggles the state of the air density correction annunciator. For the Test Function and Measurement screens, it displays the previous screen. It presents the previous ion chamber for the Detector Select screen. It decreases the dose rate unit’s divisor. For setting the start and stop exposure current thresholds, it decreases the setting.

3.9.2 Powering Up the Model 35040 Therapy Dosimeter

Pressing the POWER button turns on the instrument. Initially, the instrument runs self-tests, restores the ion chamber, temperature, pressure, air density correction status, exposure thresholds, and measurement units to their previous values, and waits for the bias supply to stabilize.

3-8

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Contents 35040 Therapy DosimeterFluke Biomedical Table of Contents Sample Customization Reports Troubleshooting and ServiceAddendum Features of Firmware Version 27JAN00 or Later Iii Blank Introduction FeaturesIntroduction Operators Manual Before You Start Safety PrecautionsSafety Symbols And Terms Specifications Factory Calibration Error Source ± %rdgMaximum Error Manual AddendaFull Scale Range Display Resolution Noise ± counts Full Scale Range Display ResolutionTimed Charge Measurements Current MeasurementsGeneral Measurements SpecificationsEffective Exposure Time Measurements High Performance Power Supply and Battery Charger Unpacking and Inspection 35040 Hardware Block Diagram of the Model 35040 Therapy Dosimeter Functional DescriptionPower Supply Front PanelMicroController Serial Communications PortBasic Operating Equations ElectrometerBias Supply Multiplexer and A/D ConverterQuantity Description Units Comments QExposureQAccum QAccumprevious= time of electrometer conversion s Charge and Current MeasurementsLeakage Measurements Exposure Charge and Dose Timed Charge and DoseSetting Thresholds Predicted Timed Charge and DoseAccumulated Charge and Dose Exposure Current and RateExposure Time DoseRate = I a × Iccf Units/C × Adcf × RateMultiplier sMm Hg = inch Hg x Air Density Correction Factor⎝ P Standard Resolution Error Units Display Minimum MaximumSetup SetupFront Panel Familiarization IntroductionPowering The System Rear Panel FamiliarizationPower-Up Self-Test and Display Messages Ion Chamber ConnectorMaking Non-Timed Exposure Measurements Basic Measurement TechniquesGeneral Considerations 3Making Timed Exposure Measurements Timer SetupTimer Use Battery Care Using Other Ion ChambersPower Battery CareOperation Instructions Front Panel ControlsPowering Up the Model 35040 Therapy Dosimeter Operation Instructions Powering Down the Model 35040 Therapy DosimeterUsing the Test Function Button QScaleFactor=1.0000 IScaleFactor=1.0000 12. The Test Function Screen Showing the Timer Settings 5Automatic Leakage CompensationCalibrated by Keithley RMD Nov 15 6Timer Setup 17. The Test Function Screen Showing the Timer SettingsUsing the Detector Select Button Using the AIR Density ButtonUsing the Units Select Button Using the Bias Select ButtonSet 300.0 V 100% Central Electrde Pos IC Bias 300.0 V CEP Using the RESET/MEASURE Button Overranging ConditionsCondition Values Overranged Reset ErrorOverrange Conditions Reset Error With Automatic Leakage Compensation Enabled AnnunciatorsAnnunciators Annunciator ConditionMeasurement Indicators and Conditions Indicator Measurement Condition? left of value Condition Overranged MeasurementInstalling/Uninstalling Customization Software CustomizationConnection to the Computer Starting the Customization SoftwareCOM Port Drop Down List DownloadingMenu Items and Controls File Save AS and File Print Ion ChambersClose or File Close Edit OK and Cancel Special ItemsDownload and Cancel 36. The Special Items Menu Calibration Temperature has focusMeasurement Displays Operators Manual Available Display Lines Display LineUsing the APPEND, DELETE, and Insert Buttons Display Line Group SelectionSelecting an Item and Placing It Changing a Line on a DisplayTimer Intervals 38. The Timer Intervals FormBias Settings 39. The Bias Settings FormExamples Changing the Pressure Units Customizing a Measurement DisplayAppending a Display Deleting a DisplayErrors Troubleshooting and Service TroubleshootingSymptom Display does not light up when Power is pressed Symptom ??Bias annunciator displayedSymptom HiBias annunciator displayed Symptom LoBias annunciator displayedSymptom Internal Reset Error displayed Symptom Configuration Error displayedBit Description Action Do not makeSymptom Current Overrange Displayed Symptom Dashes displayed instead of digitsSymptom Bias voltage measurement changes by one digit Measurements. ReturnExample 299.9 to Display Will Not Light Low Battery Hours? Is the battery voltage greater than 5.9 volts?Line Bias ErrorGo to Line Fuse Replacement Model 35040 Therapy Dosimeter Fuse ReplacementReplaceable Parts Information Interface Connector CleaningCleaning The Instrument Warranty Information Replaceable Parts ListRecalibration, Repair Information & Technical Assistance Replaceable Parts InformationBlank Sample Customization Reports Sample Documents35040 Appendix Sample Customization Reports 35040 Appendix Sample Customization Reports Blank Timed Measurements Introduction New FeaturesOverview Specifications Update Setup New Features BMaking Timed Exposure Measurements Timer Setup ProcedureTimer Use Procedure RESET/MEASURE Setup BADC ALC Automatic Leakage CompensationStart NA pA Stop Thres Current Operation Instructions BTimer Setup Decimal PlacesTable B-1. Annunciators Annunciators, Indicators, and Overrange ConditionsTable B-2. Measurement Indicators and Conditions Table B-3. Overrange Conditions Condition Overranged Measurement1Theory Of Operation Theory of OperationConfiguration Error Service Required Error Number Measurement Displays Main MenuMeasurement Menu Figure B-9 shows the Measurement Displays dialog box Table B-4. Available Display Lines Figure B-10. The Timer Intervals dialog box Page Fluke Biomedical
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