EPD/HB/40521/000 GLOSSARY Per hour °C Degrees Celsius Approved Dosimetry Service (or System) Cyclic Redundancy Check. Error checking code. dB(A) Decibels - ‘A’ weighted scale (sound intensity) Direct Current Deep Dose Equivalent (alternative nomenclature for H p (10)) Dose The accumulated dose to which alarm thresholds apply, intended for tactical dose monitoring (eg.
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EPD/HB/40521/000 Glossary (continued) Shallow Dose Equivalent (alternative nomenclature for H p (0.07)) Parts per million Random Access Memory A unit of dose equivalent, equal to 10mSv Radio Frequency Interference Short-press A short press and release of the button Sievert, SI unit of dose equivalent Tesla Thermoluminescent Dosemeter Total Dose...
EPD/HB/40521/000 WARNINGS Radioactive Contamination DURING OPERATIONAL USE THE EPD MAY BECOME EXPOSED TO RADIOACTIVE CONTAMINATION. MUST SUBJECT RELEVANT DECONTAMINATION PROCEDURES LAID DOWN BY THE RADIOLOGICAL PROTECTION AUTHORITY. Lithium Thionyl Chloride Batteries LITHIUM THIONYL CHLORIDE* (LTC) BATTERIES ARE POTENTIALLY DANGEROUS. THEY MAY LEAK TOXIC SUBSTANCES THAT CAN BE HARMFUL. READ AND TAKE NOTE OF THE MANUFACTURERS WARNINGS ON THE BATTERY CASE.
This handbook is for the Thermo Electron Electronic Personal Dosemeter (EPD) - EPD Mk2. The EPD Mk2 is lighter and slimmer than the original Thermo Electron EPD and has new micro-circuitry, case design and software. The EPD Mk2 also has a number of enhanced dosimetry features and user functions.
EPD/HB/40521/000 The new EPD also has the following major features: ♦ Improved immunity to radio frequency interference (RFI). ♦ Display Backlight. ♦ EPD communication via an infra-red interface up to a range of approximately 1 metre. ♦ Improved dose profile facility. ♦...
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The Thermo Electron supplied EasyEPD2 program reads and writes data to the EPD via the Infra-red communications link and displays the data in a PC window. Thermo Electron also produces a range of Access Control Systems for use with the EPD.
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EPD/HB/40521/000 SECTION 2 GETTING STARTED This section describes the general procedures that m ust be carried out to ensure that the EPD is set-up correctly and is functionally operational. Setting-up The EPD requires very little setting -up. Setting -up is primarily confined to: Unpacking the EPD, Inserting the battery, Checking the initialisation sequence,...
EPD/HB/40521/000 Feature Description Battery Compartment Houses an Alkaline AA battery (1.5 V) or a Lithium Thionyl Chloride (LTC) AA battery (3.6 V). Infra-red Interface Infra-red communications interface to the EPD. Button User interface for EPD control, alarm acknowledgement and LCD display selection. Sounder Provides an audible indication of an EPD alarm.
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EPD/HB/40521/000 General Precautions and Instructions Always fit new undamaged batteries of the correct type (see section 6.2). A time interval of at least 10 seconds must elapse between removal and replacement of the EPD battery (this allows the internal circuits of the EPD to power-down). The EPD is fitted with either a security-type (tamper-proof) battery cap or a coin- release battery cap, depending on customer requirements (see Figure 2.2).
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EPD/HB/40521/000 To set up the EPD for operational use the battery must be inserted/replaced in accordance with the following procedure: Read and observe the General Precautions and Instructions at the beginning of this section. If necessary remove the battery cap from the case as described in (ii) and (iii) below.
EPD/HB/40521/000 Figure 2.4 - Inserting The EPD Battery To fit the battery cap, first locate it against the special tool or coin, as appropriate) and align the battery cap tangs with the recesses in the EPD body. Push the battery cap into the battery compartment opening, ensuring that: the body of the battery cap, which houses the ( ) electrode contact...
EPD/HB/40521/000 confidence test sequence, see section 2.1.4 below. If the confidence tests pass, the EPD default display will appear. The EPD default display is preset at the factory to show Hp(10) (the penetrating or deep dose) or to another default display as specified by the customer. If a fault code is displayed, or the start-up sequence repeats, try a fresh battery.
EPD/HB/40521/000 separate, configuration for Approved Dosimetry Service (ADS). The User Name and numerical ID can only be configured via the IR communications link. Controlled and ADS User IDs can be viewed via the EPD’s LCD display. Detailed instructions to display User IDs are given in Section 3.5. 2.1.6 Wearing an EPD The EPD should be worn under the direction of the health physicist.
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EPD/HB/40521/000 WARNING DURING OPERATIONAL USE THE EPD MAY BECOME EXPOSED TO RADIOACTIVE CONTAMINATION. THE EPD MUST BE SUBJECT TO ALL RELEVANT DECONTAMINATION PROCEDURES LAID DOWN BY THE RADIOLOGICAL PROTECTION AUTHORITY. ISSUE 5 EPD TECHNICAL HANDBOOK Page 12...
‘stand -alone’ facility for users not having direct access to communications software such as EasyEPD2. However for many users the sheer number of displays available may lead to confusion and Thermo Electron has therefore provided a facility for unwanted or unnecessary displays to be disabled. Backlight Operation The EPD is equipped with a display backlight to enable the display to be read in the dark.
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EPD/HB/40521/000 backlight effect is not apparent and the user may assume that a button press operation has somehow been ‘lost’. ♦ The backlight activation causes a temporary alarm muting effect, see section 3.2.5. ISSUE 5 EPD TECHNICAL HANDBOOK Page 14...
EPD/HB/40521/000 Figure 3.2 - LCD Display Segments Audible And Visible Alarms 3.2.1 Alarm features Overview The EPD contains a sounder and alarm LED (see Figure 3.1), which are activated together when certain alarm conditions occur. Alarms are also indicated in various ways on the LCD. Under alarm conditions the LED illuminates red and the sounder sounds at 4 kHz or 2 kHz with an intensity Figure 3.1 - Alarm LED...
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EPD/HB/40521/000 Alarm Configuration The EPD is able to initiate alarms for a number of different operational conditions. The nature of any alarm is shown on the LCD display by an alarm flag (see Figure 3.2) or, in the case of an over-range alarm, by a flashing LCD display. Faults are shown as a letter ‘F’...
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Loud and High frequency. The different alarm events identified by the EPD are listed in Table 3.3. This table also shows the default alarm configurations set by Thermo Electron at manufacture. The following alarms are regenerated after a reset (e.g. battery change): •...
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EPD/HB/40521/000 In general therefore the higher priority alarms should not be configured with either a short duration, or with LED or sounder disabled, unless the lower priority alarms are also configured this way. Priority Alarm/Event Alarm Tone Frequency Volume EPD Failure Alarm. Intermittent Single Slow Tone High Loud...
EPD/HB/40521/000 3.2.2 Dose Alarms Dose alarms are checked and updated every second, except at low dose rates where this period increases to a maximum of 14 seconds. Alarms can be adjusted or inhibited via the IR communications link. Dose alarms are calculated against a preset alarm threshold set in the EPD. When the dose equals or exceeds the dose threshold the LED will illuminate, the sounder will activate and the appropriate alarm flag on the LCD will be displayed.
EPD/HB/40521/000 Figure 3.3 - Dose Rate Alarm Example The four most significant digits of the alarm ‘Off’ and the alarm 'On' thresholds can be viewed on the EPD LCD and, if user has authority to modify the thresholds, changed using the function button (see Section 3.5.9). 3.2.4 Over-Range Indication If a dose rate exceeds 1Sv/h, or if a dose store increments above 1.0Sv, an over-...
EPD/HB/40521/000 3.2.5 Alarm Muting Alarm conditions cause the sounder to be activated and the alarm LED to illuminate, subject to these facilities being enabled for the alarm. The appropriate LCD alarm flag is always activated. The user can silence ( mute ) the alarm by pressing and holding the button, provided mute is enabled on the alarm.
EPD/HB/40521/000 Button Operation and Display Selection The EPD will display a range of data to the user. The data displayed is selected by use of the button. The full range of displays is arranged on a two dimensional grid, as shown in Figure 3.4. There are a number of menus, each having a top-level display.
Any new display selected using the button remains visible for a set period of time, (Thermo Electron default time-out is 10 seconds), before returning to the default display. Some display selections (marked * in Figure 3.4) can be ‘locked-on’, i.e. the return to the default display is suspended.
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EPD/HB/40521/000 Top-Level Display Sub-Displays Display:0 Menu Button Operation: Short- Next display or lock-on Blank User ID digits User ID digits User ID digits H10 Dose HP10 H10 Dose 5,6,7,8 1,2,3,4 9,10,11,12 H10 Doses Rate * ADS User ID ADS User ID ADS User ID H07 Dose HP07...
EPD/HB/40521/000 Display Options and Button Functions The following sections describe typical displays that a user may see within each of the menus shown in Figure 3.4. This description assumes that all displays are enabled. The user may have access to any (or none) of the displays, depending on how the EPD has been configured.
EPD/HB/40521/000 Display Range: 0µSv/h to >4Sv/h (auto ranging) Note: Over-range (> 1.0 Sv/h) is indicated with a flashing LCD display. This condition is latched to warn the user that the dose value may be inaccurate. User ID Digits Short-press the button again to display the user identity number (User ID). This is a 12-digit number that is shown on three separate displays - the High 4 digits, the Middle 4 digits and the Low 4 digits.
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EPD/HB/40521/000 is used for tactical dose monitoring (e.g. per task etc.). Display Range: 0µSv to >16Sv (auto ranging). Note: Over-range (> 1.0 Sv) is indicated with a flashing LCD display. Hp(0.07)/h Dose Rate Display Short-press the button again to display the current Hp(0.07)/h dose rate.
EPD/HB/40521/000 3.5.3 Displaying Total Dose To display total dose, press and hold the button until this top-level display appears: Two sub -displays are available (in the following sub-display order): ♦ Hp(10) Total Dose ♦ Hp(0.07) Total Dose Hp(10) Total Dose Short-press the button to display the total Hp(10) dose.
EPD/HB/40521/000 ♦ Count-down Time MM:SS ♦ Reset (rSt) The count-down timer is a useful facility for activities where actions need to be completed within known time periods. The User may start, stop and reset the count down timer using the button. When the timer expires the appropriate alarm is sounded.
EPD/HB/40521/000 To turn the unit off, press and hold the button until the word ‘On’ appears: Only one sub -display is available: ♦ On/Off This function enables the EPD to be placed in sleep or OFF mode. In OFF mode power consumption is reduced considerably and the EPD stops measuring radiation.
EPD/HB/40521/000 Short-press the button to display the Peak Hp(10)/h Dose Rate: Peak Hp(0.07)/h Dose Rate Short-press the button again to display Peak Hp(0.07)/h Dose Rate: Note: Peaks can only be cleared via the IR communications link. 3.5.7 EPD Confidence Test To perform the EPD confidence test, press and hold the button until this top-level display appears:...
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EPD/HB/40521/000 seconds. This indicates that the LCD segments can be turned off, and that the tone frequencies are functional. The all-segment display will reappear for approximately 5 seconds and the LED will slow flash. The all-segment display will disappear and the default display will appear. This indicates that the confidence test has been successfully completed and that the EPD is ready for operational use.
EPD/HB/40521/000 3.5.8 Clearing Dose Displays To clear dose displays, press and hold the button until this top-level display appears: Only one sub -display is available ♦ Clr? This mode is used to clear the Hp(10) and Hp(0.07) doses. Note: The total doses are not cleared. Press the button once to select the display shown opposite.
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EPD/HB/40521/000 There are two Hp(10) alarm thresholds and a single Hp(0.07) alarm threshold that can be displayed and modified. The 2 Hp(10) dose alarm has the higher priority and should always be set to a higher value than the 1 Hp(10) alarm.
EPD/HB/40521/000 3.5.10 Displaying/Setting Dose Rate Alarm On/Off Thresholds To display and/or set dose rate alarm ON thresholds, press and hold the button until this top-level display appears: Three sub-displays are available (in the following sub -display order): ♦ Hp(10)/h Dose Rate Alarm ON ♦...
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EPD/HB/40521/000 Other values for the dose rate alarm thresholds may be set via the IR communications link. Note: To avoid false alarms due to counting statistics it is recommended that the Hp(0.07)/h dose rate alarm is not set to less than 100µSv/h Example 1 H p (10)/h dose rate on alarm threshold display set at a default...
EPD/HB/40521/000 Notes: The ‘On’ threshold must always be greater than or equal to the ‘Off’ threshold. If an attempt is made to set the ‘On’ threshold below the ‘Off’ threshold the ‘Off’ threshold will be set automatically to the same value as the ‘On’ threshold. If an attempt is made to set the ‘Off’...
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EPD/HB/40521/000 Short-press the button to display the button beep enable/disable window. To configure the beep feature 'off' or 'on' double -press the button while the EPD is displaying the following displays. Button Beep Enabled Button Beep Disabled Dose Chirp Adjustment The EPD can be configured to give a warning chirp at every preset increment in Sv and Hp(10)/h, penetrating (deep) dose.
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EPD/HB/40521/000 Pressing the button will increase the dose per chirp in the following increments: 0.0µSv, 0.01µSv, 0.05µSv, 0.1 µSv, 0.5µSv, 1.0µSv, 5µSv, 10µSv, 50µSv, 100µSv. When the required sensitivity is reached “double-pressing” the button will confirm the value and the flashing display will stop. If you start to change the sensitivity, and change your mind, the option can be aborted.
EPD/HB/40521/000 SECTION 4 TECHNICAL DESCRIPTION This section provides a technical description of the EPD and contains a summary of the EPD’s radiological features together with a summary of the EPD’s electrical, mechanical and environmental characteristics. General The EPD is of rugged construction and is suitable for most conditions that can reasonably be expected in industrial environments.
EPD/HB/40521/000 Electrical Description 4.2.1 Electrical Characteristics Power Supply: One AA Lithium Thionyl Chloride (LTC) battery 3.6 V), giving typically 5 months continuous operation at an average dose rate <5µSv/h with the alarm sounding <5 hours total during battery life. One standard AA Alk aline battery (1.5 V), giving typically 55 days continuous operation at an average dose <5µSv/h with the alarm sounding <2 hours total during battery life.
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EPD/HB/40521/000 (ii) As the battery voltage under load continues to fall, the low battery alarm flag is activated to indicate when a minimum of 10 hours battery life is remaining. Different thresholds are automatically selected for LTC or alkaline batteries. (iii) As the battery voltage under load finally falls below tolerance the EPD resets (blank display).
EPD/HB/40521/000 Mechanical Description 4.3.1 Mechanical Characteristics And Dimensions Display and function control: Single button on the front of the EPD (recessed to prevent inadvertent operation). Case material : High impact Polycarbonate/ABS blend. Clip : High impact plastic clip assembly comprising: ♦...
EPD/HB/40521/000 Environmental Description 4.4.1 Environmental Characteristics Operating Temperature : -10°C to +40°C. Storage: -25°C to +70°C. Humidity: 20% to 90% RH non condensing. Protection: IP55. Total protection against dust and against low pressure jets of water from all directions. Vibration: IEC 1526 2g, 15 min, 10 - 33 Hz Shock: 1.5 m drop on each surface onto concrete.
On the front of the EPD there is an IR communications link for reading and writing data. Communication with the EPD is usually via an IR adapter, which is connected to a host PC. EasyEPD2 is a Thermo Electron PC-based software product for maintaining, configuring and reading EPDs. The IR communication range is up to 1m, over an angle of ±30°...
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EPD/HB/40521/000 the EPD reverts to normal display. There is also an inhibit timer that prevents an EPD from re-establishing communications immediately after communications are completed. This gives the user time to remove the EPD from the IR field. The EPD continues to measure radiati on during communication.
EPD/HB/40521/000 EPD Internal Processing & Facilities This section describes the internal processing performed by the EPD and the facilities provided over the IR communications link. 4.6.1 Memory Characteristics: Memory Retention: 10-year data retention. Dose Profile History: Settable interval from two seconds to 35 hours. Stores transitions of Hp(10) and Hp(0.07) at a resolution of 1µSv.
EPD/HB/40521/000 4.6.2 Alarm Characteristics: Alarms: 2 each Hp(10) dose and dose rate alarms 1 each Hp(0.07) dose and dose rate alarms Dose and Dose Rate Alarms: 0µSv to 16Sv and 0µSv/h to 16µSv/h resolution V 1/64µSv and 1µSv/h Recommended minimum settings to avoid false alarm 7µSv/h Hp(10)/h and 100µSv/h Hp(0.07)/h Alarm Types:...
EPD/HB/40521/000 4.6.5 Dose and Dose Rate The EPD calculates dose and dose rate. Dose is accumulated in 3 stores: Dose, Total Dose and ADS Dose. Dose rate is the current rate calculated by the EPD. Dose The EPD displays Hp(10) (penetrating or deep) dose and Hp(0.07) (superficial or shallow) dose.
EPD/HB/40521/000 seconds below 1mSv/h. Due to limitations in the processing and memory available, this time constant cannot be reduced when rapid changes are observed, and the Hp(0.07)/h dose rate is approximated as the sum of Hp(10)/h and the beta dose rate. This approximation means that at low gamma energies (below 50 keV) the Hp(0.07)/h dose rate typically under-responds by up to 25% in comparison to the Hp(0.07) dose response.
EPD/HB/40521/000 4.6.7 Dose Quality Flags There are 7 dose quality flags set within the EPD. Dose quality can only be read and cleared via the IR communications link. They are normally cleared at the start of an Issue period. The dose quality flags are as follows: (i) Reset Count The reset count flag is a count of the number of times the unit has been reset, either removing and re-fitting the battery,...
EPD/HB/40521/000 the unit has either been exposed to some kind of extreme interference or has developed a fault. (vi) Abuse Warning The abuse warning indicates that an abuse alarm has been activated. An abuse alarm is activated if mechanical shocks are detected continuously for greater than 45 seconds (see Shock Time Seconds) (vii) CRC Failure The CRC failure flag is set as a result of an integrity check on a set of data indicating...
EPD/HB/40521/000 Alarm thresholds are set via the IR communications link, or by the button if the user is granted authority (see Figure 3.4), to any value in the following ranges: & 2 Hp(10)/h 0µSv/h to 16.777215 Sv/h Hp(0.07)/h 0µSv/h to 16.777215 Sv/h &...
EPD/HB/40521/000 Detectors State. This is the current state of the EPD’s operating mode, i.e. ON or OFF. Alarms The EPD retains a record defining which of the following alarms has occurred. The record is normally cleared by system software at the start of an issue period: 3 Dose Alarm Flags As section 4.6.8 3 Dose Rate Alarm Flags.
EPD/HB/40521/000 Disabled. The EPD is not calculating dose. 4.6.10 Dose Profile The EPD stores Hp(10) and Hp(0.07) dose to a resolution of 1µSv in non-volatile store so that a profile of the dose over time can be recreated. The interval between stores is set-up via the IR communications link.
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EPD/HB/40521/000 Events On Events Off Code Text as displayed by Code Text as displayed by EasyEPD2 EasyEPD2 Failure Alarm on Failure Alarm off Over Range Alarm on Over Range Alarm off Hp10 Dose Alarm 2 on Hp10 Dose Alarm 2 off Hp07 Dose Alarm on Hp07 Dose Alarm off Hp10 Dose Alarm 1 on...
EPD/HB/40521/000 SECTION 5 EPD FAULTS and RECOVERY ACTIONS Overview This section identifies the fault conditions that can occur and describes the recovery procedure (if any) to be taken to restore the EPD to operational use. The section is organised as follows: 1.
EPD/HB/40521/000 Visual and Audible Fault Indication An EPD failure is usually indicated by a visual and audible alarm. In most instances the EPD will display an error code on the LCD and the LED will flash. The default audible alarm is as follows: Alarm rate: ___ ___ ___ ___ slow intermittent rate If alarm mute is enabled for the fault alarm the sounder can be silenced and the alarm Led extinguished by the action of pressing and holding the button.
EPD/HB/40521/000 Internal Logging of Fault Conditions 5.3.1 EPD Status Faults Record The EPD logs data to an internal data record in EEPROM, to indicate that faults have occurred. These faults are as follows: Event Logged. An event (dose alarm or a fault) has been logged in the EPD’s event history store.
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EPD/HB/40521/000 Note: The date/time data field wraps round after 194 days of operation. After this time previous event-associated day/date(s) cannot be considered as accurate. In addition elapsed time during loss of power is not recorded. ISSUE 5 EPD TECHNICAL HANDBOOK Page 64...
EPD/HB/40521/000 Blank LCD Display and Other Faults It may also be possible for the EPD to fail without producing or displaying an error code, or causing an alarm, for example due to failure of the micro-controller or digital circuit. A list of such faults and the recommended course of action is given in the table below.
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EPD/HB/40521/000 Confidence Test ♦ Enable sounder if required Sound fails to operate in Sounder Disabled alarm condition ♦ Contact supplier. Faulty LED Hardware fault No visual alarm during Confidence Test ♦ Enable LED if required LED Disabled LED fails to operate in alarm condition ♦...
EPD/HB/40521/000 Initialisation Error ( LCD ---- ) A series of single dashes appearing on the LCD display indicates an initialisation error following a reset or battery change: Initialisation errors typically refer to corruptions to data in the EPD’s non volatile memory (EEPROM).
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EPD/HB/40521/000 An EPD will only raise this condition if it is first triggered by the system software, in effect a message is passed to the EPD saying: “raise an alarm if the following write operations don’t complete successfully within ‘N’ seconds.” If the condition does occur then it is necessary to train the users not to remove the EPD from the IR field until indicated ( i.e.
EPD/HB/40521/000 LCD Display Error Codes Faults that exhibit a known condition are normally indicated on the EPD LCD as ‘F’ followed by a 3-digit error. The error code number is also logged in the Event History store, with date/time data. As an example the following shows fault F095: A list of EPD error codes is given in Table 5.2.
Fault Log Form ( Appendix D ). If a faulty unit is to be r e turned to Thermo Electron it must be returned in a fully decontaminated and reasonably clean condition. The battery must be removed but kept with the unit.
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EPD/HB/40521/000 If the unit is to be restored to operational use, clear down all faults on display and in the Fault Status Record, using EasyEPD2. This is to ensure that any subsequent faults are detected. Control Module Code Text as displayed by Recommended Remarks EasyEPD2...
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EPD/HB/40521/000 Services Module Code Text as displayed by Recommended Remarks EasyEPD2 Action Customer Action Service Module stCalData Reset unit. Return to CRC faulty supplier if recurs. Service Module Reset unit. Return to stRateThres CRC faulty supplier if recurs. Service Module Reset unit.
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EPD/HB/40521/000 EEPROM Module Code Text as displayed by Recommended Remarks EasyEPD2 Action Customer Action EEPROM no more spare Write Return to supplier All 9 spare sectors have been sectors available aband used. This fault is unlikely to oned. occur in normal operation. Tests have shown that the EEPROMs are very resilient ( >...
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EPD/HB/40521/000 Counts Module Code Text as displayed by EPD Action Recommended Remarks EasyEPD2 Customer Action Unexpected Texas chip Reset unit. No Longer Used reset (Battery Low but no Return to Batt Low Status) supplier if recurs. Consecutive Drop (more No Longer Used than 45 seconds) Counts not latched yet Reset into...
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EPD/HB/40521/000 Code Text as displayed by EPD Action Recommended Remarks EasyEPD2 Customer Action Hard Gamma detector fail* None- continues Reset unit. Only the first normal processing Return to detector to fail is supplier if logged. recurs. Soft Gamma detector fail* None- continues -ditto- -ditto-...
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Electron has no control over any subsequent adjustments made by the end user to these factors. Thermo Electron can therefore not warrant the calibration of these EPDs once they have left the factory. As such, Thermo Electron accepts no liability for the accuracy of the radiological response of these EPDs.
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A change in EPD calibration is usually indicative of a fault in the EPD and, due to the complexity of achieving calibration over the full energy range, it is recommended that any EPDs that fail calibration checks are returned to Thermo Electron for repair, recalibration or replacement.
EPD/HB/40521/000 The EPD Battery The EPD can use either a Lithium Thionyl Chloride (LTC) 3.6 V battery or a standard 1.5 V AA battery (see Section 4.2). A battery change is within the scope of any competent user. However, care must be taken when replacing the EPD battery (see Section 6.2.3).
EPD/HB/40521/000 going to be left non-operational for any length of time to avoid the possibility that leakage may occur and damage the EPD. 6.2.3 Lithium Thionyl Chloride Battery Warning Lithium Thionyl Chloride (LTC) (Sulphurous Oxychloride, SOCl ) batteries are potentially dangerous and can be harmful. The following warnings are to be observed when inserting/replacing the EPD battery.
EPD/HB/40521/000 the battery should be removed from the EPD using protective clothing, gloves, and goggles. (ii) the battery should be placed in a self-sealing polythene bag (or equivalent) and disposed of in the correct manner (see below). (iii) Wash with copious amounts of water any areas that come into contact with the electrolyte, especially the skin.
EPD/HB/40521/000 EPD Clip Assembly Depending on customer requirements, the EPD may (or may not) be fitted with a clip assembly. The clip assembly comprises a lanyard plate and a spring clip, which allows the user to attach the EPD to an outer garment (see Section 2.1.6). The clip assembly is attached to the EPD by the lanyard plate.
EPD/HB/40521/000 Figure 6.2 - EPD With Clip Assembly 6.3.1 Removing the EPD Lanyard Plate/Clip Assembly To remove the lanyard plate/clip assembly, proceed as follows: If the spring clip is fitted to the lanyard plate, open the jaws of the clip by pushing downwards (see Figure 6.2) to give access to the lanyard plate.
EPD/HB/40521/000 Insert a screwdriver, with a blade width of 3 to 4 mm, under the lanyard plate tang and apply downward leverage on the screwdriver (see Figure 6.4). At the same time, push the lanyard plate towards the bottom of the EPD so as to disengage the lanyard plate from the retaining lugs.
EPD/HB/40521/000 Cleaning The EPD is a sealed unit and has protection against dust and low pressure jets of water from all directions. The unit will not withstand prolonged immersion under pressure. Cleaning should be carried out if the unit requires general cleaning, if the EPD battery has leaked or if the unit has come into contact with radioactive contamination.
EPD/HB/40521/000 the leakage the EPD should be considered as unusable and the manufacturer contacted for advice. 6.4.4 Periodic Cleaning The EPD should be cleaned by wiping it over periodically with a cloth lightly dampened with a solution of water and up to 5% of a neutral water-based detergent. ISSUE 5 EPD TECHNICAL HANDBOOK Page 86...
EPD/HB/40521/000 APPENDIX A RADIOLOGICAL SPECIFICATIONS The following specifications quoted apply under standard conditions of 20°C. Energy response ♦ Photon Hp(10) ±50% 15keV to 17keV (Ref. Cs-137) ±20% 17keV to 1.5MeV (Ref. Cs-137) ±30% 1.5MeV to 6MeV (Ref. Cs-137) ±50% 6MeV to 10MeV (Ref. Cs-137) ♦...
EPD/HB/40521/000 APPENDIX B ELECTROMAGNETIC COMPATIBILITY Standard Test The EPD was tested to the following specification with no failures: Test Type Specification Test Frequency Range Level Notes Radiated Mil Std 416D RS103 10kHz – 40 GHz 200V/m Susceptibility E- Field Radiated Def Stan 59-41 DRS02 14kHz –...
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EPD/HB/40521/000 Chart 1 10000 1000 1000 10000 100000 Frequency (Hz) Chart 1. The tested Mk2 EPDs were not susceptible to H-field radiation below the above graph. ISSUE 5 EPD TECHNICAL HANDBOOK Page 90...
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EPD/HB/40521/000 Chart 2 1400 1200 1000 1000 10000 100000 Frequency (MHz) Chart 2. The tested Mk2 EPDs were not susceptible to E-field radiation below the above spot frequencies (100kHz-100GHz carrier wave). ISSUE 5 EPD TECHNICAL HANDBOOK Page 91...
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EPD/HB/40521/000 Chart 3 2500 2000 1500 1000 Frequency (GHz) Chart 3. The tested Mk2 EPDs were not susceptible to E-field radiation below the above spot frequencies (0.1GHz - 100GHz pulsed 1kHz 1µS) ISSUE 5 EPD TECHNICAL HANDBOOK Page 92...
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EPD/HB/40521/000 APPENDIX C SUMMARY OF GENERAL PHYSICAL & FUNCTIONAL CHARACTERISTICS Feature Characteristic 1.5V Alkaline AA or 3.6V Lithium Thionyl Chloride Battery Type (LTC) AA batteries. ( Observe Manufacturers warnings. ) Dimensions Diameter : 13.9 to 14.6 mm, Length : 49.0 to 51.0 mm. Typical Life 5 months (LTC), 55 days (Alkaline), continuous...
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IR communication to front of unit, range up to 1m. use standard IrDA adapters ( physical level 1 ) with ions & Internal Thermo Electron supplied DLL and application s/w as Data required ( EasyEPD2, Access Control s/w etc. ).
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( Cyclic Redundancy Check ). Calibration. EPDs normally supplied with Calibration factors in the ‘locked’ state and only changeable by Thermo Electron. On request Thermo Electron will supply units with calibration factors unlocked. Dose Data User ‘dose’ readings also include detector counts and verification associated ‘quality’...
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EPD/HB/40521/000 essential ). Controls Various controls are possible over the communications interface to configure displays, sounder operation, detector and self test, clear dose and detector counts, analyse and clear faults, set alarm thresholds and alarm characteristics, turn the EPD On or Off, enable and disable controls via the button, adjust the dose profile and special store operation.
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Owning Organisation: Site or Location: REPORT NO.: Related / Repeated Report Nos.: Raised By: Date: Contact / Telephone dd/mm/yyyy EPD Supplier ( Thermo Electron or Form Returned to: Distributor ): BATTERY Type (Alkaline or LTC): Manufacturer: Supplied by: EPD Serial No.s: Date/Time fault occurred: Fault type, e.g.
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