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GasTech D-Guard2 Скачать руководство пользователя страница 55

D-Guard

2

52

16.

Connecting A HART Field Communicator

For D-Guard

2

detectors that are fitted with HART communications, interaction with the detector may be done via a

HART master communication device such as a HART field communicator / configurator or a system controller.

HART enabled D-Guard

2

detectors are optionally fitted with an IP68 rated connector (communications port) to allow

convenient connection to a field communicator.

Before connecting any communications device to the D-guard

2

communications port, the user MUST check

that the equipment is safe to use within the hazardous area classification that the detector is installed into.
The terminal parameters of the communications device MUST be compatible with those stated in this
manual for the D-Guard

2

communications port. Failure to adhere to either of these requirements could

lead to dangerous and potentially life threatening conditions being created

A suitable cable to connect between a standard field communicator and the D-Guard

2

is available from GasTech.

Connections at the communicator are polarity independent.

To start communications, open the communications port waterproof cap and plug the data connector into the port.

D-Guard

2

is by default set to polling address 0 and is set for point to point (variable current loop) operation.

D-guard

2

does not use Device Description type files and will be discovered as a generic device to a field communicator.

Once successful communication has been established, the HART communication icon will start to flash (refer to
section 13.1.1).

For complete details regarding D-Guard

2

HART communications, refer to the D-Guard

2

HART specification document

(This document is available from the Gastech website www.gastech.com.au/dguard-2).

Remove the waterproof cap to access the communications port. Note that the detector is rated IP68 ONLY if this cap or the
mating connector are in place. Without the cap or connector fitted rating is IP66 only.

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Содержание D-Guard2

Страница 1: ...t 61 8 6108 0000 e info gastech com w gastech com Digital Gas Detector with HART communications OPERATOR S MANUAL ...

Страница 2: ...D Guard2 1 This Page Left Intentionally Blank ...

Страница 3: ...AL INSTALLATION PRACTICES 16 9 3 DETECTOR DIMENSIONS AND MOUNTING ORIENTATION 16 9 4 MANDATORY INSTALLATION CONSIDERATIONS 17 9 4 1 Typical Barrier Connection 17 9 4 2 Intrinsically Safe Power Supply Connection 18 9 4 3 Maintaining Conditions of Certificate Conformity 19 9 5 MOUNTING THE ENCLOSURE 19 9 5 1 Mounting Surfaces and Environment 19 9 5 2 Detector Location 20 9 6 ELECTRICAL CONNECTIONS 2...

Страница 4: ...NSE TIME TEST FUNCTION 39 12 6 1 Running the DRT Checks 39 13 DETECTOR CONFIGURATION 40 13 1 SENSOR CONFIGURATIONS 40 13 1 1 Set Guard Band 40 13 1 2 Set Measurement Full Scale 41 13 1 3 Detector Type 41 13 1 4 Setting Span Gas Concentration 42 13 2 ALARM CONFIGURATION 42 13 2 1 Making Alarm Configuration Changes Alarm 1 shown 43 13 2 2 Alarm 1 Trip Level 43 13 2 3 Alarm 1 Hysteresis 43 13 2 4 Ala...

Страница 5: ...OR MAINTENANCE 53 17 1 VISUAL INSPECTION 53 17 2 HANDS ON DETAILED INSPECTIONS 53 17 3 GAS SENSING CELL REPLACEMENT 54 17 3 1 Removing the Detector Main Board 54 17 3 2 Replacing the Sensor 54 17 4 GENERAL DETECTOR REPAIR 55 17 5 DISPOSAL OF D GUARD2 COMPONENTS 55 18 APPENDIX A 56 18 1 OUTPUT CURRENT SIGNAL TOTAL LOOP RESISTANCE VS POWER SUPPLY VOLTAGE 56 18 1 1 Loop Resistance Group I D Guard2 Wi...

Страница 6: ...ecifications 63 24 1 3 Carbon Dioxide Detector Specifications 64 24 1 4 Electro Chemical Detector Specifications 64 24 1 5 Mechanical Environmental Specifications 64 25 APPENDIX H PRODUCT CERTIFICATES 65 25 1 IECEX PRODUCT CERTIFICATE 65 25 2 ATEX PRODUCT CERTIFICATE 69 26 APPENDIX I PRODUCT DIMENSIONS 73 ...

Страница 7: ...logos are trademarks of their respective owners DISCLAIMER Under no circumstances will Gastech be liable for any claims losses or damages resulting from or arising out of the repair of or modification to the equipment by a party other than Gastech or its authorised service representatives or by operation or use of the equipment other than in accordance with the printed instructions provided by Gas...

Страница 8: ... to perform all needed repairs to restore the instrument to full operating condition including reactivation or replacement of all out of warranty electrochemical cells You may send the unit freight prepaid to Gastech Pty Ltd 24 Baretta Rd Wangara Western Australia WA 6065 Attn Service Department Enclose the copy of your contact details Pack the instrument and all its accessories preferably in its ...

Страница 9: ...vision 2 of Part V of the Act other than that implied by section 69 of the TPA the liability of the Company for such breach shall subject to section 68A 2 of the TPA be limited to one of the following as determined by the Company a the replacement of the Equipment or the supply of equivalent Equipment b the payment of the cost of replacing the Equipment or of acquiring equivalent Equipment 5 Subje...

Страница 10: ...ation of the conditions of certification and additionally create hazardous operating conditions D Guard2 Carries the following Group II Hazardous area certifications Ex ia IIC T4 Ga 20 C Ta 70 C II 1G Ui 28V Ii 93mA Pi 0 7W Ci 0 Li 0 Includes All Electro Chemical sensor versions covering both standard ranges and user specified types Excludes Infra Red types 65 1080 LEL 65 1080 CH4 65 1080 CO2 Ex i...

Страница 11: ... The detector must be powered from an intrinsically safe source of power This may be either an intrinsically safe power supply or a safe area located non intrinsically safe power supply via the use of an appropriate approved safety barrier Certification and identification labels fixed to this sensor must not be damaged removed modified or covered before during or after installation Must not be use...

Страница 12: ...information as part of its serial number identification label Group I Marking all product variants may carry this label Group IIC Marking all product variants except 65 1080 LEL 65 1080 CH4 65 1080 CO2 may carry this label Group IIB Marking all product variants may carry this label These makings provide information identifying the sensor type certification number and its safety classification This...

Страница 13: ... shipping boxes and protective packaging for items attached to them especially if the wrapping are to be discarded 4 2 Inspection Equipment that is found to be damaged or appears to have been modified in any manner must not be used Please contact Gastech if the equipment is suspected to be different than that ordered or if it does not match the published specifications 4 3 Storage Where equipment ...

Страница 14: ...fe Use of Equipment Equipment as supplied has been manufactured within the controls of relevant International and or Australian Standards and state legislative requirements Equipment identified within this manual has been designed for a specific purpose therefore any modification or damage to it must be reported to the manufacturer to allow for repair or replacement The instructions within this ma...

Страница 15: ... carried out by the end user product certification will be invalidated End users may change the gas measurement range and displayed gas name via the configuration menus however GasTech Australia will not accept responsibility for nor accept liability for damage or injury caused by instruments rendered unsuitable for any particular application following such changes The facility for configuring the...

Страница 16: ...2 should contain the following components Gas Detector assembly Quick Start Card Combined enclosure splashguard key and calibration magnet Manufacturing Quality certificate If the received package is incomplete please contact Gastech or the distributor that supplied the product Refer to Section 4 for unpacking and storage information ...

Страница 17: ...as ventilation that affect the rate at which diffusion occurs In most cases over a long enough time the concentration of gas anywhere within the space will have equal concentration However in areas with enclosed spaces with poor ventilation gas may pool in higher concentrations if the rate of gas leakage into the space is greater than the rate of diffusion out of it Pooling can occur in roof space...

Страница 18: ...cation into which the detector is to be installed is correctly understood Any system intended to mitigate the risk of injury needs to be properly designed and implemented Such a system must be the result of structured risk analysis with the outcomes used to help define the safety system requirements Such risk assessments will take into considerations the nature of the application along with its pr...

Страница 19: ...ntry port is clear of obstruction which would prevent the passage of gas into the internal detector cell Prevent water and dust accumulation from affecting operation by mounting the sensor unit with the gas entry port pointing forwards or downward Do not install the instrument with the gas entry port facing upwards as this may allow the collection of water or dust to prevent gas entering the senso...

Страница 20: ... to be located outside of the hazardous area 9 4 1 Typical Barrier Connection GasTech Part Number 57 9010 01 Safe Area GasTech Part Number 57 9010 02 Hazardous Area Connections between D Guard2 and other connected equipment must have compatible entity parameters When selecting a power source such as an isolation barrier pay close attention to the terminal entity parameters for the barrier to ensur...

Страница 21: ...6W may have entity parameters such as Uo 16V Io 1 0A Co 6uF Lo 33uH These must be compared to the entity parameter limits for the connected equipment D Guard2 Ui 22V Group I certified variant Ii 105mA D Guard2 is internally fuse resistor limited Ci 0 D Guard has a capacitance value of zero appearing at its input terminals Li 0 D Guard has an inductance value of zero appearing at its input terminal...

Страница 22: ... by design and by the IP66 IP68 level of protection that D Guard2 has Incorrectly tightened cable glands or front face may lower or even remove this level of protection 9 5 Mounting the Enclosure The D Guard2 enclosure provides two mounting feet that are external to the enclosure These are located to the left and right of the instrument and can accommodate screw bolt sizes up to M8 9 5 1 Mounting ...

Страница 23: ...ases to be monitored can assist in deciding on optimal locations Permissible exposure levels are covered by various health and safety standards and are not reproduced in this manual A characteristic of significant interest is the buoyancy of the gas in air essentially whether it is more or less dense than air Knowing this can provide some indication of areas of possible pooling or areas near a poi...

Страница 24: ...eturn connection is located to the bottom right of the circuit board as viewed from the rear of the board shown in the diagram below Removing the lid of the enclosure exposes a number of critical system elements that must be treated with care in order to maintain the operational integrity of the instrument Avoid touching the circuit board with hands or tools Avoid disturbing the sealing gasket tha...

Страница 25: ...r when the lid is removed replaced Once the cable is positioned as required tighten the cable gland nut to hold the cable in place and create the waterproof seal When connecting direct to the main system board connections are first made to the power plug supplied with the instrument and the plug is then engaged into the power socket as shown above The plug and socket are keyed for correct alignmen...

Страница 26: ...ze of the apparent changes in gas reading due to electrical noise could be sufficiently large to cause the detector to enter an alarm state especially for instruments with low alarm ranges such as 1ppm or less With proper cable shielding noise can be dramatically reduced or eliminated allowing the response from the detector to properly represent the ambient gas conditions The normal detector respo...

Страница 27: ...have been made to the instrument the front cover lid must be refitted correctly to maintain the IP66 68 ingress protection rating The enclosure base is fitted with a sealing gasket that is located in a groove that runs around the perimeter of the opening Before replacing the cover check that the gasket is present and seated correctly in the groove The gasket must not be twisted stretched or out of...

Страница 28: ... unless fully competent to do so and only with the knowledge that it is safe to do so Ensure that power to the detector is isolated at the controller side of the installation Visually check that detector mounting conforms to information given in this manual Check that all electrical connections within the detector s are correct per this manual Conductors should be marked and coded at each end for ...

Страница 29: ...he site area where the detector is installed and must be used only as instructed in its operational manual by appropriately trained personnel Bump test procedures involve the use of toxic gases The gas concentrations used for test and calibration purposes are considered non harmful over the time period for which testing is likely to occur It is however the responsibility of the personnel carrying ...

Страница 30: ... return terminals Doing so may cause damage to the detector electronics Do not operate the unit with the cover removed if the installation area and or conditions do not permit it Current loop access must then be via connections in the safe area The bump test procedure should be carried out as follows example assumes a 0 100ppm H2S detector Decide on the appropriate method for viewing the readings ...

Страница 31: ...der example 49 2 ppm Note the scale configuration of the detector under test e g 0 100ppm This is a 100ppm full scale detector Divide the test gas concentration by the detector full scale number in this case 49 2 100 giving 0 492 Multiply this number by 16 in this case 0 492 x 16 giving 7 872 Add 4 to the above result in this case 7 872 4 giving 11 872 The final result is the expected loop current...

Страница 32: ...or all gas readings status messages and menu items The detector uses four magnetically sensitive switch devices that operate as user buttons keys The functionality of each button is context dependant based on the menu screen in use This system of soft keys is described in section 10 3 1 11 1 Detector Power Up For the first sixty seconds following power up D Guard2 displays the start up screen This...

Страница 33: ... of the detector s target gas and its full scale measuring range Temperature This reading indicates the temperature within the detector body The temperature value may differ from ambient temperature by a few degrees Icon Locations Depending on the status of the detector and or specific menu pages these locations on the display will be occupied by status icons When an icon is not active its place i...

Страница 34: ...e key and performs the action that is assigned to it at the time Return Home Present Location you are here Start Action Next Location where this key will take you Although the function of the keys change based on context there are only a small number of basic key function icons to remember There are also a number of fixed key function locations to simplify navigation to common screens such as the ...

Страница 35: ...tylus must be held on the padlock icon continuously for a few seconds Depending upon whether a pass code has been set the next screen will either be the menu choice bars CAL SET or the screen for entering the pass code Padlock Icon for 2 5 seconds Menu is unlocked To enter the pass code scroll each digit up or down A padlock icon will show once a code is entered Entering an incorrect code will mov...

Страница 36: ...n new This signal degradation can be observed as a baseline measurement shift either positive or negative Similarly the cell s sensitivity to gas will reduce with a corresponding reduction in output signal for a given gas concentration If left uncorrected eventually the detector will no longer operate reliably in detecting its intended gas In order to maintain accurate and reliable operation the d...

Страница 37: ...ring this time the trend bar may be observed for a stable reading as D Guard2 checks for a stable reading If the baseline gas concentration is greater than 10 of the detector s full scale a warning to apply purge gas is displayed A flashing gas cylinder icon is also displayed The Run Auto Cal soft key will not operate at this stage If not already connected connect the purge gas supply to the detec...

Страница 38: ...ether a reading is rising falling or has stabilised by just looking at the displayed numbers The trend indicator will settle at the middle position once the raw sensor signal has stabilised and sat within a narrow band of values for around 5 seconds Once the trend indication is in the centre position the reading can be deemed stable enough to calibrate within the detectors specified accuracy limit...

Страница 39: ...ve Observing the trend indicator will show when the gas reading has stabilised If the marker is in the centre position then the auto span process can be started If the marker is not in the centre position the sensor has not stabilised and auto span is not possible To continue operate the Run Auto Cal soft key Running the Auto Span Process Unstable Reading Warning After the Run Auto Cal soft key ha...

Страница 40: ...nual Span Calibration After entering the Span calibration screens 12 4 4 Performing a Manual Span Calibration When entering the span calibration functions the auto span page is the first one entered Operate the Manual Span soft key to move on to the manual span calibration pages Once in the manual span screen and span gas has been applied the warning messages and icons will extinguish The gas read...

Страница 41: ... the correct range Each time a change is made the home icon will change to the save icon One a value is saved the icon will revert to the home icon Further changes will again show the save icon The final value must be 4 00mA 0 01mA From the 4mA calibration screen 12 5 2 Setting the 20mA output Current From the 4mA calibration screen operate the SET 20mA soft key to move to the 20mA calibration scr...

Страница 42: ...e start of the checks The target timing values are shown in the upper status banner Once test gas is applied the test begins automatically A message indicating the test is running is displayed Note it is absolutely essential to use the same span gas concentration each time this test is carried out This gas concentration must be set in the user calibration gas setup menu see section 12 1 4 If the s...

Страница 43: ...d from the Quick Nav screen the main Sensor setup screen is shown Select the SETTINGS soft key to start sensor configuration 13 1 1 Set Guard Band This setting allows the user to set or disable the measurement guard band or zero suppression that assists in keeping the detector s baseline readings stable This suppression band is hard coded into D Guard2 and holds the readings at zero only whilst th...

Страница 44: ...value than the default Increments are in units of 5ppm Note that if the full scale range is set too high for the current detector gain setting readings may become unstable Gas type is selected by the use of the up and down soft keys When a change is made the home icon changes to the save icon When the changes are saved the detector reboots to make the changes effective 13 1 3 Detector Type This se...

Страница 45: ...eeprom Once saved the save icon reverts to the back icon allowing the previous setup function to be accessed if required To move to the Set Auto Zero screen operate the NEXT PARAMETER soft key To return home keep pressing the back soft key until the main sensor setup screen is displayed with the home icon showing 13 2 Alarm Configuration D Guard2 contains 2 gas concentration based alarms that prov...

Страница 46: ... decrease the value The keys are accelerated to make the increments decrements move more quickly as the key is held To move back to the previous screen operate the BACK arrow soft key To move to the next parameter to change use the NEXT PARAMETER soft key Note if these keys are operated before the save icon is visible any changes made will not be saved Alarm 1 Trip Level Adjusted 13 2 3 Alarm 1 Hy...

Страница 47: ...hanges will return the back arrow icon to the save icon Use the NEXT PARAMETER soft key to move to the next parameter to change Alarm Normal State Alarm Normal State sets whether a relay when fitted is in an energised or de energised condition under normal non alarm operating conditions The default is always normally energised since this provides failsafe indication of power failure to the detecto...

Страница 48: ...etc Data Setup is accessed from the Quick Nav Screen 13 3 1 HART Setup Main Screen To access the HART data setup unlock the menu and operate the DATA soft key The main HART setup page displays the features that may be configured by the user Operate the SETTINGS soft key to start configuration 13 3 2 Turning HART Communications On or OFF Alarm 1 Latching Changed 13 2 7 Alarm 2 Current Settings Scre...

Страница 49: ... is indicated 13 4 System Configuration The system configuration screen allows configuration of the detector in a general sense such as detector isolation System Setup is accessed from the Quick Nav Screen 13 4 1 SYSTEM Setup Main Screen To access the SYSTEM data setup unlock the menu and operate the SYSTEM soft key The main SYSTEM setup page displays the features that may be configured by the use...

Страница 50: ...he detector display can be set to appear as normal black on white images or as an inverted white on black image Changes are automatically saved 13 4 5 Sensor Temperature Compensation Sensor temperature compensation may be turned on or off as required Compensation against temperature changes is optimised for the sensors supplied with the detector and those supplied by Gastech Changing to sensor typ...

Страница 51: ...If the detector reading exceeds the full scale measurement range by 10 the OVER RANGE message is displayed and four dashed markers show in place of the readout Additionally the sensor fault icons is displayed since an over range condition can also be the result of a sensor failure If the gas sensing element is producing a signal that forces the reading into a negative state possibly due to poor ca...

Страница 52: ...sor life remaining can be viewed on the detector information screen This fault is cleared by changing the sensor re calibrating the detector and resetting the sensor life counter 14 2 Fault Log And Information Screens 14 2 1 Detector Fault Log 14 2 2 Detector Information Screen The detector information screen contains the units serial number the date of manufacture hardware and firmware revisions ...

Страница 53: ...ll signal this via a message in the lower status bar Additionally a static alarm bell icon will be displayed If the detector has relays fitted the warn relay will activate The behaviour of the alarm bell icon will depend on whether latching or non latching alarms have been configured If the measured gas concentration reaches the set point programmed into the detector for a danger condition the det...

Страница 54: ...cleared by using the alarm clear soft key This is the upper right bell icon with the cross adjacent to it Clearing an alarm must only be done by an authorised person If the conditions that triggered the alarm are still present the alarm will activate again 15 1 7 Setting The display Heading Banner By default the heading at the top of the main measurement screen is the set gas type and range This b...

Страница 55: ...y life threatening conditions being created A suitable cable to connect between a standard field communicator and the D Guard2 is available from GasTech Connections at the communicator are polarity independent To start communications open the communications port waterproof cap and plug the data connector into the port D Guard2 is by default set to polling address 0 and is set for point to point va...

Страница 56: ...taminant ingress Check that door seals are in good condition Verify that labels fixed to equipment such as enclosures wall boxes and cables are present and in good condition allowing clear visibility of the information and identification they convey especially certification labels Verify that no unauthorised modifications have been carried out on equipment 17 2 Hands On Detailed Inspections More d...

Страница 57: ...ss to the sensor follow the steps given below Note ensure that this is only done by a suitably trained or qualified person Disassembly of D Guard2 must not be carried out in a hazardous area It is strongly advised to wear an antistatic wristband and use an antistatic mat to place the detector PCB onto when working on replacing the sensor Remove the four lid retaining screws Unplug the power cable ...

Страница 58: ...2 has reached the end of its service life it must not be treated as general waste The electro chemical cells used to detect gas contain substances that could potentially create an environmental hazard Under no circumstances should the cells be incinerated by the user since they could release toxic fumes When cells are replaced by Gastech Gastech will properly dispose of the used items Disposal of ...

Страница 59: ...ate safely with the ability to drive the loop to 22mA fault signalling Incorrect allowance for system resistances and power supply voltages may result in the detector being unable to correctly signal the measured gas concentration The graphs below show the relationship between detector power supply voltage output and maximum loop resistance for both Group I and Group II versions of D Guard2 Note t...

Страница 60: ...D Guard2 57 18 1 3 Loop Resistance Group II D Guard2 With Backlight Disabled loop at 22mA 18 1 4 Loop Resistance Group II D Guard2 With Backlight Enabled loop at 22mA ...

Страница 61: ...o disable the backlight LEDs to gain additional voltage compliance for the current loop output to function up to 22mA Disabling the LEDs gives around 130 Ohms extra available loop resistance at 22mA or will allow the supply voltage to be operated 3 0V lower for a given loop resistance Determining whether the backlight link needs to be fitted requires an understanding of the characteristics of the ...

Страница 62: ...of the enclosure materials with exposure to these substances will depend on the nature of the application therefore the information given below is for guidance only Substance Gas Reaction Notes Ammonia 10 v v Severe reaction PPM levels of ammonia will give no problems Benzene Excellent Butane Excellent Calcium hyperchlorite Severe reaction Carbon Monoxide Excellent Carbon Tetrachloride Excellent C...

Страница 63: ... 6 0 0 1 0 0 SO2 20 0 15 n a 4 1 1 NO2 10 0 25 100 5 n a 100 NO 50 8 0 110 n a 0 4 0 4 C2H4 400 52 0 5 30 0 0 Cl2 10 1 20 38 5 100 n a NH3 20 0 n a 0 0 0 1 0 2 0 2 CO2 5 0 0 0 0 0 1 0 0 0 03 As an example 400ppm of hydrogen sulphide would produce a response equivalent to 180ppm in a carbon monoxide sensor per the table value of 45 cross sensitivity 0 45 x 400ppm 180ppm equivalent response The actu...

Страница 64: ...a toxic gas sensor to positive transients is about 3 times greater than for negative transients Infra Red sensors will respond equally to positive and negative pressure shifts Detectors should not be located in sealed rooms with doors that may be opened and closed rapidly or in locations where ventilation systems can create pressure pulses 22 4 Humidity The electrochemical cells used in D Guard2 d...

Страница 65: ...D Guard2 62 23 APPENDIX F 23 1 System Menu Map ...

Страница 66: ...ds upon model see table 2 gas types and ranges GS 4 Measurement Accuracy Refer to Sensor Performance tables GS 5 Maximum Loop Current Under any condition of operation or fault 30 mA GS 6 Minimum Supply Voltage at 20mA Minimum operating voltage at detector 13 0 VDC GS 7 Maximum Supply Voltage Ui Group I variant Group I maximum input voltage entity parameter Ui 22 VDC GS 8 Maximum Loop Resistance Gr...

Страница 67: ...AS2290 3 ANZ60079 29 and AS4641 SS 6 Stated accuracy temperature limits 20 c to 40 C SS 7 Operating temperature limits 20 C to 50 C SS 8 Operating humidity range 15 to 90 SS 9 Operating pressure range 80kPa to 120kPa SS 10 Pressure effects Negligible for steady state above or below 101 3kPa SS 11 Humidity effects uncompensated Negligible for steady state above or below 60 RH SS 12 Long term drift ...

Страница 68: ...D Guard2 65 25 APPENDIX H Product Certificates 25 1 IECEx Product Certificate ...

Страница 69: ...D Guard2 66 ...

Страница 70: ...D Guard2 67 ...

Страница 71: ...D Guard2 68 ...

Страница 72: ...D Guard2 69 25 2 ATEX Product Certificate ...

Страница 73: ...D Guard2 70 ...

Страница 74: ...D Guard2 71 ...

Страница 75: ...D Guard2 72 ...

Страница 76: ...D Guard2 73 26 APPENDIX I Product Dimensions ...

Страница 77: ...D Guard2 74 Doc_Rev 03 12 15 ...

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