Fluke 35040 manual 3Making Timed Exposure Measurements, Timer Setup, Timer Use

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Operation

3

Basic Measurement Techniques

Procedure:

•The annunciator line on the Measurement screen displays "WAIT System Not RDY" while the instrument is acquiring the minimum number of samples required for leakage compensation. Wait for this message to disappear.

•Wait for the leakage current to return to the nominal value.

•Make the exposure.

When the instrument senses that the exposure is over, it displays and holds the exposure measurements and then resets the electrometer (refer to Section 3.9.7 for information on configuring the start and stop thresholds). The exposure measurements are displayed until either the RESET/MEASURE button is held for one second, the bias voltage or threshold changed, or another exposure is started.

3.7.3Making Timed Exposure Measurements

The timer is available when any of the measurement displays contains a timed measurement. Refer to Section 3.10 for information on customizing measurement displays.

Timer Setup

Procedure:

•Use the TEST FUNCTION button, along with the UP and DOWN arrows to display the Timer Setup screen.

•To modify the timer setup, press the TEST FUNCTION button to display the "f" cursor at the timer interval field and use the UP and DOWN arrows to select a timer interval from the programmed list. (Refer to Section 3.10 for information on how to program the interval list.)

•Press the TEST FUNCTION button to advance the "f" cursor to the timer count mode field and use the UP and DOWN arrow keys to select up (UP) or down (DOWN) for the count mode.

•Press the TEST FUNCTION button to advance the "f" cursor to the timer decimal places field and use the UP and DOWN arrow keys to select zero (0) or one (1).

•Press the TEST FUNCTION button to hide the cursor and save any changes. Proceed to using the timer, which is discussed next.

Timer Use

Procedure:

•Press the RESET/MEASURE button to show the Measurement screen if it is not displayed.

•To start or manually stop the timer, press the RESET/MEASURE button while the instrument is updating other exposure measurements (e.g., charge and current). The instrument displays the “Tmr” annunciator when the timer is running.

NOTE

The instrument will not permit the timer to be started while leakage is being measured.

•Upon completion of the timer interval or if the instrument senses the exposure is over (applicable when automatic leakage compensation is enabled), the instrument ceases updating the timed measurements.

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Contents Therapy Dosimeter 35040Fluke 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 Factory Calibration Error Source ± %rdg SpecificationsMaximum Error Manual AddendaFull Scale Range Display Resolution Full Scale Range Display Resolution Noise ± countsTimed Charge Measurements Current MeasurementsGeneral Measurements SpecificationsEffective Exposure Time Measurements High Performance Power Supply and Battery Charger Unpacking and Inspection 35040 Functional Description Hardware Block Diagram of the Model 35040 Therapy DosimeterFront Panel Power SupplyMicroController Serial Communications PortElectrometer Basic Operating EquationsBias Supply Multiplexer and A/D ConverterQExposure Quantity Description Units CommentsQAccum QAccumprevious= time of electrometer conversion s Charge and Current MeasurementsLeakage Measurements Timed Charge and Dose Exposure Charge and DosePredicted Timed Charge and Dose Setting ThresholdsAccumulated Charge and Dose Exposure Current and RateDoseRate = I a × Iccf Units/C × Adcf × RateMultiplier s Exposure TimeMm Hg = inch Hg x Air Density Correction Factor⎝ P Units Display Minimum Maximum Standard Resolution ErrorSetup SetupFront Panel Familiarization IntroductionRear Panel Familiarization Powering The SystemIon Chamber Connector Power-Up Self-Test and Display MessagesMaking Non-Timed Exposure Measurements Basic Measurement TechniquesGeneral Considerations 3Making Timed Exposure Measurements Timer SetupTimer Use Using Other Ion Chambers Battery CareBattery Care PowerOperation 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 5Automatic Leakage Compensation 12. The Test Function Screen Showing the Timer SettingsCalibrated by Keithley RMD Nov 15 17. The Test Function Screen Showing the Timer Settings 6Timer SetupUsing the AIR Density Button Using the Detector Select ButtonUsing the Bias Select Button Using the Units Select ButtonSet 300.0 V 100% Central Electrde Pos IC Bias 300.0 V CEP Overranging Conditions Using the RESET/MEASURE ButtonCondition Values Overranged Reset ErrorOverrange Conditions Annunciators Reset Error With Automatic Leakage Compensation EnabledAnnunciators Annunciator ConditionIndicator Measurement Condition Measurement Indicators and Conditions? left of value Condition Overranged MeasurementCustomization Installing/Uninstalling Customization SoftwareConnection 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 Special Items OK and Cancel36. The Special Items Menu Calibration Temperature has focus Download and CancelMeasurement Displays Display Line Operators Manual Available Display LinesDisplay Line Group Selection Using the APPEND, DELETE, and Insert ButtonsSelecting an Item and Placing It Changing a Line on a Display38. The Timer Intervals Form Timer Intervals39. The Bias Settings Form Bias SettingsExamples Customizing a Measurement Display Changing the Pressure UnitsAppending a Display Deleting a DisplayErrors Troubleshooting Troubleshooting and ServiceSymptom ??Bias annunciator displayed Symptom Display does not light up when Power is pressedSymptom HiBias annunciator displayed Symptom LoBias annunciator displayedSymptom Configuration Error displayed Symptom Internal Reset Error displayedBit Description Action Do not makeSymptom Dashes displayed instead of digits Symptom Current Overrange DisplayedSymptom Bias voltage measurement changes by one digit Measurements. ReturnExample 299.9 to Display Will Not Light Hours? Is the battery voltage greater than 5.9 volts? Low BatteryLine Bias ErrorGo to Model 35040 Therapy Dosimeter Fuse Replacement Line Fuse ReplacementReplaceable Parts Information Interface Connector CleaningCleaning The Instrument Replaceable Parts List Warranty InformationRecalibration, Repair Information & Technical Assistance Replaceable Parts InformationBlank Sample Documents Sample Customization Reports35040 Appendix Sample Customization Reports 35040 Appendix Sample Customization Reports Blank Timed Measurements Introduction New FeaturesOverview Specifications Update New Features B SetupMaking Timed Exposure Measurements Timer Setup ProcedureTimer Use Procedure Setup B RESET/MEASUREAutomatic Leakage Compensation ADC ALCOperation Instructions B Start NA pA Stop Thres CurrentDecimal Places Timer SetupTable B-1. Annunciators Annunciators, Indicators, and Overrange ConditionsTable B-2. Measurement Indicators and Conditions Condition Overranged Measurement1 Table B-3. Overrange ConditionsTheory 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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