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MAKING ION CHAMBER MEASUREMENTS

1.

Allow the system to reach equilibrium by selecting dose rate mode and waiting at least three
minutes.  Do not touch digitizer. One does not need to shut the system off when replacing
chambers, however, do not disconnect the chamber when actual measurements are being made. 
Each time a new chamber is used, the system must re-stabilized

.

Note: For changing environments, allow 10 minutes per 10 C for the sensor/electronics to
equilibrate.

2.

Ensure that the system is set to high sensitivity on 
(Setup->Mode SELECT->High sensitivity->On).  This ensures that the system performs a fine
zero (as opposed to a coarse zero) prior to every measurement.

3. 

Do not move or touch the digitizer or the ion chamber during the zero measurement interval. If
low-level measurements are being made and there is a significant delay between measurements
(> 2-3 minutes) it is prudent to force a full re-zero by exiting the mode and re-entering.

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Summary of Contents for Accu Series

Page 1: ...The Accu Series Accu Pro Accu Dose Accu kV Radiation Measurement Systems User Guide...

Page 2: ...d Monrovia CA 91016 4591 USA USA 626 357 7921 Fax USA 626 357 8863 email Service radcal com www radcal com Radcal Part MCD 9096 4091099 Rev K4 Firmware V6 08 Accu Pro Firmware V7 03 V7 23 Accu Dose Fi...

Page 3: ...ensors 23 Diode Sensors 25 Ion chambers 25 Ion Chamber Dose Timing Specifications 25 Waveform Output 36 Part numbers 36 OPERATOR MESSAGES 37 Self test 37 Accu kV 37 Ion chambers and dose diodes 38 ACC...

Page 4: ...ber or the dose diode digitizer and the DDX6 W or DDX6 M sensors Using these sensors in conjunction with the kV sensors provides dose and dose rate measurements synchronized to an x ray pulse Using 40...

Page 5: ...Diagnostic Ion Chamber and kV Sensor Components A Accu Pro 9096 Control Unit B 40x12 W Diagnostic Range kV Sensor C 10X6 6 Ion Chamber Sensor D Positioner E 9660 Ion Chamber Digitizer F 90C6 4 Sensor...

Page 6: ...ment with the Radcal logo facing you It will click into place To remove it pinch the levers on the side of the connector and pull back Connect the kV sensor to the sensor cable Hold the round connecto...

Page 7: ...arger Connect the charger to the control unit and plug it into an ac outlet The charge indicator should turn on orange indicating the battery is being charged The instrument can operate while the batt...

Page 8: ...ne of the display will then show Change or SELECT and the second line will show setup or whatever measurement mode was active the last time power off occurred If self test is unsuccessful a failure me...

Page 9: ...060 mR min KV Pulse test Diagnostic sensor 40 160kV Press UP or DN until the display shows Change or SELECT kV Pulse Press select After a few seconds the display changes to kV Pulse W while the kV sen...

Page 10: ...nsor For a Tungsten Rhodium setting you will see a T in the lower left of the display after you select kV pulse On pressing the test button you then have the display show 31 6kVp Txx xxmR 100ms A Tung...

Page 11: ...For changing environments allow 10 minutes per 10 C for the sensor electronics to equilibrate 2 Ensure that the system is set to high sensitivity on Setup Mode SELECT High sensitivity On This ensures...

Page 12: ...dicates default filtration will be used 2 5 mm Aluminum for the diagnostic sensor 30 m Molybdenum for the Mammography sensor M indicates a user selected filter other than 2 5 mm Al T indicates a Tungs...

Page 13: ...se and Dental modes provides exposure information if a dose sensor or Accu kV diode is connected and displayed Sounds A brief 5ms 4 kHz tone is produced whenever a key press is recognized A longer 100...

Page 14: ...ambers that measure radiation dose and the diode based radiation sensors Also available are mA sensors used to determine x ray anode current KV sensors The Accu kV sensors use differential absorbers a...

Page 15: ...ments Chamber For leakage measurements Cross section of 100cm 2 Also for very low dose to image receptor 10X6 1800 The Radiation Protection Chamber For very low level radiation measurements such as sh...

Page 16: ...ter Their energy response is not as uniform as the 10X6 ion chambers Their directional response makes them unsuitable for CT scatter and leakage measurements Temperature dependent leakage current make...

Page 17: ...Auto Dose Automatically measures the dose and duration of a single exposure Displays the result until another exposure occurs Starts when the dose rate exceeds 0 01 FS stops accumulating dose 200 ms a...

Page 18: ...econd computes and displays the result and then repeats Displayed values change slightly to adapt to a continuous waveform Width measurements are omitted dose and mAs become dose rate and average mA r...

Page 19: ...s Seconds Minutes Hours X X X Mammo anode filter Mo Mo W Ag W Rh X X DAC output kV mA Rel intensity dose rate X X 1 The Accu Pro measures the background zero when you select a dose mode If high sensit...

Page 20: ...is relative dose rate is dose rate in nR sec for 10X6 6 3 55 5 92 10 184 18 330 30 550 55 1000 100 1840 182 3300 300 5500 500 9200 Acquire Delay Number of frames 1 256 converted to time based on selec...

Page 21: ...w for proper measurement Battery LOW appears and the system will not respond to select The instrument turns off when the batteries are depleted 1000 to 6000 mAh NiMH cells are recommended It takes app...

Page 22: ...tware required to implement this communication is automatically installed with XLPRO 4 A virtual serial port driver is available contact Radcal for details Connect a USB cable from the PC to the Accu...

Page 23: ...gnment tube anode cathode vs sensor long axis 1 kV for 10 Width accuracy 2 ms 5 sec 0 1 of value 0 2 ms Ripple Error Displayed kVp 0 8 kV for 10 0 to peak ripple 4 kHz Filtration kV uncorrected 0 7kV...

Page 24: ...rt axis 0 5 kV for 5 Alignment tube anode cathode vs sensor long axis 0 5 kV for 10 Long term drift 0 5 kV for 1 yr Width accuracy 2 ms 5 sec 0 1 of value 0 2 ms Ripple Error Displayed kVp 0 5 kV for...

Page 25: ...nce conditions Ion Chamber Dose Timing Specifications Measuring time pulse width The Auto Dose mode provides a pulse width time measurement capability when you use either ion chambers or dose diodes F...

Page 26: ...Gy s Dose 200 R 2 0 MR 2 Gy 17 kGy Auto Dose Threshold 72 mR s 631 Gy s Calibration 4 60 Co Rate Dependence 2 3 mR s 180 R s Energy Dependence 5 45 keV 1 33 Mev Construction C552 air equivalent walls...

Page 27: ...1 17 Gy s Dose 100 R 589 kR 1 Gy 5 kGy Auto Dose Threshold 22 mR s 189 Gy s Calibration 4 60 Co Rate Dependence 2 10 mR s 100 R s Energy Dependence 5 40 keV 1 33 Mev with buildup cap Construction C55...

Page 28: ...589 kR 1 Gy 5 kGy Auto Dose Threshold 22 mR s 189 Gy s Calibration 4 150 kV 10 2 mm Al HVL Rate Dependence 2 10 mR s 100 R s Energy Dependence 5 3 20 mm Al HVL Construction C552 air equivalent walls e...

Page 29: ...Auto Dose Threshold 2 mR s 19 Gy s Calibration 4 60 kV 2 8 mm Al HVL Rate Dependence 5 0 4 mR s 80 R s Pulse 500R s 50 s Energy Dependence 5 30 keV 1 33 Mev with buildup material Construction Coaxial...

Page 30: ...se Threshold 2 mR s 19 Gy s Calibration 4 20 kV 0 26 mm Al HVL Rate Dependence 5 20 mR min 600 R min Energy Dependence 5 10 keV 40 keV Construction Parallel plate with 0 7 mg cm 2 metallized polyester...

Page 31: ...nGy 1 0 mGy Auto Dose Threshold 216 R s 2 Gy s Calibration 4 150 kV 10 2 mm Al HVL Rate Dependence 5 2 mR min 199 R min Energy Dependence 5 20 keV 1 33 MeV with buildup material Construction Parallel...

Page 32: ...s Dose 1 R 5 9 kR 10 nGy 52 Gy Cine per frame 0 01 R 100 mR 0 1 nGy 1 0 mGy Auto Dose Threshold 216 R s 2 Gy s Calibration 4 50 kV 0 88 mm Al HVL Rate Dependence 5 2 mR min 199 R min Energy Dependence...

Page 33: ...150 kV 10 2 mm Al HVL Rate Dependence 2 2 mR s 40 R s Energy Dependence 5 3 20 mm Al HVL Construction Concentric cylinder 9 mm dia x 142 mm 10 cm active length 5 uniformity of response over central 9...

Page 34: ...7 Gy Auto Dose Threshold 72 R s 1 Gy s Calibration 4 150 kV 10 2 mm Al HVL Rate Dependence 5 20 mR hr 2 kR hr Energy Dependence 5 30 keV 1 33 MeV with buildup material Construction Parallel plates 118...

Page 35: ...shold 7 R s 63 pGy s Calibration 4 150 kV 10 2 mm Al HVL Rate Dependence 0 5 0 1 mR hr 20R hr 10 65 R hr Energy Dependence 5 30 keV 1 33 MeV with buildup material Construction Concentric cylinder 138...

Page 36: ...umber Control Unit 9096 Sensor Cable 4m 90C6 4 Diagnostic Accu kV sensor with auto compensation 40X12 W Mammographic Accu kV sensor 40X9 Mo Dose diode digitizer DD60 Diagnostic Dose diode sensor DDX6...

Page 37: ...rror These errors arise from problems with the x ray signal After two seconds the messages become kV try again and Error cleared and a new measurement can be performed Too narrow 1 2 3 Waveform was to...

Page 38: ...es These messages arise when measuring dose and dose rate using ion chambers or the DDX6 dose diodes Starting a measurement Dose sync fail Press SELECT to retry While measuring zero Zero too small Pre...

Page 39: ...Figure 24 Control Unit Configuration 39...

Page 40: ...Figure 25 Connector Locations 40...

Page 41: ...ol unit If the green LED illuminates it is not very bright the Radcal USB software is installed on the PC otherwise you need to install XLPRO version 4 or later Turn on the Accu Pro wait for self test...

Page 42: ...res absolute value of mA 0 2 mA accuracy 5 As or 0 2 mAs accuracy 1 s pulse Input impedance Fixed resistive 1 ohm plus fuse and wiring Withstands1500 vac between input leads and control unit 77 s samp...

Page 43: ...ater of 3 4 digits or 015mA mA accuracy 4 of reading Limited by 0 6mA RMS noise below 15mA mAs accuracy 1 s pulse 4 of reading Limited by 0 6mAs RMS noise below 15ma 77 s sample rate 2 6 at 720Hz 3 dB...

Page 44: ...at holds calibration and chamber type information the Accu Pro requires A temperature sensor is included to provide that information also Its diameter is slightly larger than that of the chamber stem...

Page 45: ...base of the chamber positioner locate the kV sensor relative to the ion chamber to control the effect of backscatter from the kV sensor on exposure measurements Because mammography measurements using...

Page 46: ...Accu Pro System Carrying Cases 46...

Page 47: ...Silver track to refine the 22 to 24 kV range to obtain a few more tenths accuracy if required from 22 to 24 kV An example Selenia calibration is shown below A Tungsten Silver setting is different from...

Page 48: ...placement parts nor shall Radcal be liable for any defective material replaced without Radcal s consent during the period of this warranty Radcal reserves the right to perform warranty services at its...

Page 49: ...conforms to the following product specifications EMC EN 50081 2 EN 555011 Class A EN 50082 1 IEC801 2 4 kVcd 8 kVAD EN 50082 1 IEC801 3 3V m Note The Analog Output is intended for use by trained user...

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