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1. 4 8 Grounding and Transient 4 9 BO ual rac 4 10 Connector 5 11 Determining the Cause of Malfunctions eeeeeeeeeseeieeeeeeenen eene enin nn nnn nn natn nn sna nsns 5 12 Warranty and 6 Appendix A Connectors Wiring Angle Conversion 13 Appendix B Measuring Temperature with 4 20 mA Tiltmeters and Clinometers 15 Appendix Calibration Certificates 22 1 Introduction DeepWater 42015 a precision tiltmeter inclinometer designed for underwater measurements and other applications involving high external pressures Figure 1 It offers durability unrivaled sensitivity and long term stability under these demanding conditions DeepWater tiltmeters are an excellent choice for monitoring the behavior of underwater structures such as dams oil pla2. Curve U S Sensors LR252B1K 60000 50000 40000 Ohms 30000 20000 10000 B 06 1004 Rev A 20 0 20 Degrees Celsius Figure 13 Thermistor resistance vs temperature 60 to 70 C 19 40 60 80 APPLIED GEOMECHANICS Resistance vs Temperature for 2500 Ohm Thermistor with B Type Curve U S Sensors LR252B1K 40000 35000 30000 25000 20000 Ohms 15000 10000 5000 40 35 30 25 20 15 10 5 Degrees Celsius Figure 14 Thermistor resistance vs temperature 40 to 0 C APPLIED B 06 1004 Rev A 20 GEOMECHANICS Resistance vs Temperature for 2500 Ohm Thermistor with B Type Curve U S Sensors LR252B1K 7000 6000 5000 4000 Ohms 3000 2000 1000 Degrees Celsius Figure 15 Thermistor resistance vs temperature 0 to 50 C APPLIED GEOMECHANICS B 06 1004 Rev A 21 Appendix C Calibration Certificates APPLIED QA B 06 1004 Rev A 22 GEOMECHANICS
3. INSIDE THE TILTMETER APPLYING DC CURRENT THROUGH THE SENSORS WILL CAUSE PERMANENT DAMAGE THAT IS NOT COVERED BY THE WARRANTY 10 Connector Maintenance 1 Do not expose the connectors to long term heat or sunshine If this occurs and the connectors are very dry soak in fresh water before use 2 Keep the connectors lubricated The recommended lubricant is Molykote 44 Medium Use sparingly half a match head per contact is adequate 3 Sand or mud in the female contact should be removed with fresh water Failure to do so could result in splaying of the female contact and damage to the O ring seals 4 Do not overtighten the bulkhead nut 5 Do not disconnect by pulling on the cable Avoid sharp bends at cable entry 6 When disconnecting pull straight not at an angle 7 Do not apply angular loads shears to the bulkhead connector as they can damage or destroy the connector 11 Determining the Cause of Malfunctions Apart from the procedures described below your DeepMater 420 tiltmeter is not field serviceable If you encounter problems not described here please contact Applied Geomechanics in Santa Cruz California at telephone 831 462 2801 fax 831 462 4418 or email us at applied geomechanics com A service engineer will assist you in determining the cause of any problem If the tiltmeter output is firmly pegged at either end of its output range the tiltmeter may be tilted off scale Rotate the tiltmeter in the
4. Rev A 2 5 Measuring Tilt Rotation Wiring of the current loop circuit s is shown in Figure 6 for uniaxial tiltmeters and in Figure 7 for biaxial tiltmeters Typically a shunt resistor is used to create a voltage drop in the current loop The difference in the voltages on opposite sides of the shunt resistor is then measured and used to compute the current using Ohm s Law Figure 6 Ohm s Law states that J AV R where I is current AV the voltage drop difference and R the resistance of the shunt resistor The tilt angle is linearly proportional to the current The approximate scale factors for standard and wide angle tiltmeters are listed in the specification table above The precise scale factor s for your tiltmeter are shown on its calibration certificate which is contained in Appendix C or has been provided as a separate document When the tiltmeter is level the current output is approximately 12 mA Your tiltmeter requires a minimum of 10 Volts DC power input Vsuppi y to generate 20 mA of current when it is rotated to the positive end of its range However the shunt resistor raises the ground potential for the tiltmeter circuit so that the minimum power supply voltage depends on the resistance of the shunt resistor The equation for this voltage is in the specification table on the Power Requirements line and is graphed in Figure 8 The maximum power supply voltage should never exceed 29 Volts DC A simple operational
5. of the Model 904 T Clinometer Pak This product houses the TULIP clinometer in a rugged weatherproof enclosure e Tuff Tilt 420 The 4 20 mA version of the Model 801 Tuff Tilt The Tuff Tilt 420 is a high precision tiltmeter with 4 20 mA output e DeepWater 420 The 4 20 mA version of the fully submersible Model 802 DeepWater tiltmeter housed in a 316 stainless steel enclosure e Tulip SC A 4 20 mA signal conditioning card for use with all of our Miniature Tilt Sensors Each of these products also measures temperature using a thermistor mounted on the circuit board The thermistor resistance is nonlinearly proportional to temperature In other words while the tilt output is measured using a 4 20 mA current loop the temperature is indicated by the resistance of the thermistor The wiring diagram for measurements is shown below in Figure 12 B 06 1004 Rev A 15 supply AF cultfr 4 20 A current loop lack i e o jue 2 e e Temperature Excitation RT Thermistor 250 Yell range e Temperature hi e e Temperature Returr Tiltmeter Figure 12 Uniaxial tiltmeters Tilt angle is measured by the 4 20 mA current loop Current is measured indirectly using a shunt resistor Ohm s Law states that V V IR where I is current in Amperes R resistance in Ohms and V and V the voltages measured on opposite sides of the sense resistor Temperature is measu
6. 8 Grounding and Transient Protection High voltage transients are the most common cause of failure of field instruments in outdoor installations In a typical occurrence a high voltage spike from a lightning strike or power surge travels along the cable until it encounters the instrument s electronic circuitry where the delicate low voltage components are overloaded and fail Surge protection circuitry is designed to reduce the likelihood of such failures by attenuating voltage differences within the circuit and between the circuit and ground The two wires of each current loop are connected inside your tiltmeter by a variable resistance type surge absorber tranzorb Under normal operating conditions the tranzorb is an open circuit and no current flows through it between the two wires However when the potential on one wire exceeds that on the other by more than 30 Volts the resistance of the tranzorb begins to drop until at even higher voltages the tranzorb behaves like a direct short This behavior has the effect of equalizing the potential on both sides of the current loop reducing the possibility of arcing through the circuit and attendant damage This is a very basic level of transient protection It will not prevent arcing to ground if the common mode voltage in the tiltmeter wires is sufficiently high with respect to the local earth ground potential Additional transient protection may be provided by earthing the DeepWater 420 enclosur
7. User s Manual DeepWater 420 Submersible Tiltmeters With 4 20 mA Output Serial No Standard 3 range uniaxial transverse configuration Standard 3 range uniaxial longitudinal configuration Standard 3 range biaxial Wide angle 50 range uniaxial transverse configuration Wide angle 50 range uniaxial longitudinal configuration Wide angle 50 range biaxial APPLIED ANN GEOMECHANICS 140 Chestnut Street San Francisco CA 94111 Phone 415 364 3200 Fax 415 861 1448 www geomechanics com Tel 831 462 2801 Fax 831 462 4418 e mail applied geomechanics com www geomechanics com OOOOOU WARNING NEVER USE AN OHMMETER TO MEASURE THE TILT SENSORS INSIDE THE TILTMETER APPLYING DC CURRENT THROUGH THE SENSORS WILL CAUSE PERMANENT DAMAGE THAT IS NOT COVERED BY THE WARRANTY Copyright 2006 by Applied Geomechanics Inc All rights reserved Manual No B 06 1004 Rev A Printed in USA TABLE OF CONTENTS 1 Teri o B T 1 2 I eiunichi lc 1 3 Specificato m nio a e ree e eter Sec eet ct I 2 4 Dimensions and Tilt Polarity 2 5 Measuring Tilt 1 11 1111 11 nn Enn 3 6 Measuring Temperature 3 7 Installing the
8. WER REQUIREMENTS Vs 0 02 Ampere x R 10 VDC lt Vs lt 29 VDC where Ris the resistance of the shunt resistor and loop wiring in Ohms ENVIRONMENTAL 40 to 85 C operating and storage 240 bars 3500 psi pressure rating ENCLOSURE amp MOUNTING 316 stainless steel O ring in lid CABLE amp CONNECTOR 6 conductor male bulkhead connector with O ring seal shipped with mating 45cm 18 inch neoprene cable whip longer cables available cable has 20 AWG conductors and no shield SIZE amp WEIGHT DeepWater 420 Order Numbers 152 x 102 x 89 mm 6 x 4 x 3 5 inches 5 kg 11 Ib greater range available Spare Parts amp Accessories Standard Range Wide Angle Uniaxial Transverse 98043 01 98043 02 Additional cable specify length Uniaxial Longitudinal 98043 03 98043 04 Additional mating female connector Biaxial 98043 05 98043 06 Delrin locking sleeve 4 Dimensions and Tilt Polarity Figure 1 shows the directions of positive and negative tilt for uniaxial tiltmeters with a longitudinal tilt configuration Longitudinal tilt is the same as Y tilt in biaxial tiltmeters Figure 2 shows the directions of positive and negative tilt for uniaxial tiltmeters with a transverse tilt configuration Transverse tilt is the same a X tilt in biaxial tiltmeters Dimensions of the DeepMater 420 tiltmeter are shown in Figures 4 and 5 B 06 1004
9. at our option products that prove to be defective during the warranty period provided they are returned prepaid to Applied Geomechanics Inc AGI No other warranty is expressed or implied The warranty is void if the equipment is subjected to lightning strikes or other large potential gradients or if it is otherwise used contrary to the directions herein After expiration of the warranty AGI will repair the equipment at its factory for parts and labor charges Products returned after watranty expiration should be accompanied by a purchase order to cover repair costs Applied Geomechanics Inc is not liable for consequential damages THE REMEDIES PROVIDED HEREIN ARE THE BUYER S SOLE AND EXCLUSIVE REMEDIES AGI SHALL NOT BE LIABLE FOR ANY DIRECT INDIRECT SPECIAL INCIDENTAL OR CONSEQUENTIAL DAMAGES WHETHER BASED ON CONTRACT TORT OR ANY OTHER LEGAL THEORY B 06 1004 Rev A 8 r Figure 1 Biaxial DeepWater 420 tiltmeter showing Y tilt direction and polarities This direction is the same as longitudinal tilt in uniaxial versions of the tiltmeter Figure 2 Biaxial DeepWater 420 tiltmeter showing X tilt direction and polarities This direction is the same as transverse tilt in uniaxial versions of the tiltmeter B 06 1004 Rev A Neoprene connector 1 Delrin locking sleeve B 06 1004 Rev A Figure 3 High Pressure Connector and Cable Whip Figure 4 Tiltmeter dimension
10. check that you should perform after receiving your tiltmeter is to connect it to power and then tilt it manually in first the positive and then the negative direction While doing so verify that the output swings through the full range of 4 mA negative tilt to 20 mA positive tilt 6 Measuring Temperature There are two ways to measure temperature in uniaxial tiltmeters see Appendix B for details 1 Measure the resistance of the thermistor between the Temperature Excitation and Temperature Out wires Then convert that resistance to temperature using the information in Figure 9 2 Use the thermistor as a voltage divider Apply a known voltage to the Temperature Excitation wire and connect the Temperature Return wire to ground Then measure the voltage on the Temperature Out wire with reference to ground Follow instructions in Appendix B to convert that voltage to temperature This method is only available in uniaxial tiltmeters To prevent self heating and inaccurate temperature readings apply power to the thermistor for less than one second when making temperature measurements B 06 1004 Rev A 3 7 Installing the Tiltmeter Mount your DeepWater tiltmeter directly onto a solid horizontal surface using four No 10 or M4 screws The drill pattern for the mounting holes is shown in Figure 5 Make sure the screws are tight Small movements caused by a loose attachment will be measured by the tiltmeter
11. e For more complete transient protection we recommend the use of commercially available surge protectors such as those made by Citel www citelprotection com or PolyPhaser www polyphaser com 9 Routine Maintenance The routine maintenance procedures given here will help ensure that your tiltmeter provides many years of trouble free service Keep your tiltmeter clean and away from extremes of heat and cold Dirt and extreme temperatures shorten the life of the seals and unnecessarily stress the electronic components Keep the tiltmeter out of direct summer sun because solar radiation can create internal temperatures much higher than the ambient temperature in some cases higher than the rated storage temperature of the tiltmeter To ensure that your tiltmeter maintains its waterproof seal make sure that the connector and the screws securing the lid are tight before submergence The O ring in the lid is made of nitrile Buna N and can be replaced if damaged by Parker O ring size 2 247 The O ring should be lubricated with a light coating of silicone grease such as Dow Corning 112 B 06 1004 Rev A 4 The electrolytic tilt sensor in your tiltmeter is a stable robust and shock tolerant device One of the few things that can damage it is Direct Current DC which causes electrolysis and plating of the electrodes NEVER use an ohmmeter which uses DC to test the tilt sensor WARNING NEVER USE AN OHMMETER TO MEASURE THE TILT SENSORS
12. e divider circuit to determine temperature equation 2 must be rewritten to account for the resistance R of the Temperature Excitation and Temperature Return wires Vout Vin R25 R RT3 R25 2R eq 4 Rearranging gives this equation for thermistor resistance RT3 R25 R Vin Vou 1 R eq 5 You must decide whether lead wire resistance is important enough to take it into consideration in your measurements For temperatures around 25 C and a 500 ft 152m cable wire resistance is about 1 of the thermistor resistance The temperature error caused by not taking wire resistance into consideration is lt lt 1 C In geotechnical and earth science applications temperature trends and relative changes are normally more important than highly accurate absolute temperature readings In some of these applications lead wire resistance may not be important B 06 1004 Rev A 17 For further information on the properties and use of thermistors for temperature measurement visit the U S Sensor Corp website www ussensor com The thermistor used in your tiltmeter has a B type curve and is U S Sensor part no LR252B1K WARNING NEVER USE AN OHMMETER TO MEASURE THE ELECTROLYTIC TILT SENSOR INSIDE THE TILTMETER APPLYING DC CURRENT THROUGH THE SENSORS WILL CAUSE PERMANENT DAMMAGE THAT IS NOT COVERED BY THE WARRANTY B 06 1004 Rev A 18 70000 Resistance vs Temperature for 2500 Ohm Thermistor with B Type
13. e with a waterproof splice The tables below give wire color coding and connector pin assignments A drawing of the connector pin configuration follows the table Figure 11 olor in DIe 0 1 Black Ground 2 White Temperature Return 3 Red Vsuppiy loop power 4 Green Not used 5 Yellow Orange Temperature Out 6 Blue Temperature Excitation 777 Black Ground tilt 1 2 White Ground Y tilt 3 Red VsuppLy X loop power 4 Green Vsuppcy Y loop power 5 Yellow Orange Ground Temperature 6 Blue Temperature Excitation Figure 11 Face view of male connector on tiltmeter B 06 1004 Rev A 13 11 3600 17453 17 453 0 2094 oorr 1 2909 278x10 0 01667 EFE 4 848 4 85x10 5 82 107 53x10 3 44x10 02063 0 001 120107 0 0573 3 436 206 3 1000 0 0120 TF 4 775 286 5 17189 83333 83 33 06 1004 14 Appendix B Measuring Temperature with 4 20 mA Tiltmeters and Clinometers APPLIED aA GEOMECHANICS 140 Chestnut Street San Francisco CA 94111 Phone 415 364 3200 Fax 415 861 1448 www geomechanics com e mail applied geomechanics com www geomechanics com Introduction Applied Geomechanics offers five tilt measurement products with 4 20 mA output e TULIP A board level clinometer similar to voltage output Models 901 and 902 e Clinometer Pak 420 The 4 20 mA equivalent
14. ltage divider see Figure 12 By applying a known voltage V at the end of the Temperature Excitation wire and measuring the voltage Vou on the Temperature Out wire the thermistor resistance is obtained indirectly as shown below Both Vin and Vou referenced to ground at the end of the Temperature Return wire The equation for Vou is Vout Vin R25 RT3 R25 eq 2 Rearranging gives R25 Vin Vout 1 eq 3 As shown by equation 3 the input voltage can vary during your measurements What is important however is that the ratio of the input voltage to the output voltage Vin Vou be accurately known Once your have obtained the value of RT3 from equation 3 use Figures 13 14 and 15 or equation 1 to obtain the internal tiltmeter temperature If your tiltmeter has a long cable you will improve the accuracy of your thermistor resistance measurements by subtracting cable resistance from your readings Applied Geomechanics tiltmeter cables contain stranded copper conductor wires with a gauge of 24 AWG Each wire has a resistance of approximately 26 Ohms per 1000 ft 85 Ohms km at 25 C In the case of a 1000 ft cable and direct resistance measurement using an Ohmmeter you would subtract 2 x 26 Ohms from your reading to get the true resistance of RT3 Thus a total of 52 Ohms would be subtracted accounting for the resistance of the two wires through which the measurement was made If you plan to use the voltag
15. ly Minimum Power Requirement as a Function of Shunt Resistor Value Minimum Power Requirement Volts B 06 1004 Rev A 100 200 300 400 500 600 700 800 900 1000 Shunt Resistor Value Ohms Figure 8 Minimum power requirement vs shunt resistor value 10 Resistance vs Temperature for 2500 Ohm Thermistor with B Type Curve U S Sensors LR252B1K 70000 60000 50000 40000 Ohms 30000 20000 10000 60 40 20 0 20 40 Degrees Celsius y Figure 9 Thermistor resistance vs temperature T B Ln RT3 C La RT3 3 D Ln RT3 5 273 15 where T is in degrees Celsius and RT3 thermistor resistance A 7 34862E 04 B 3 38205E 04 C 1 30862E 07 D 1 21751E 09 B 06 1004 Rev A 11 Figure 10 Interior of biaxial DeepWater 420 showing gold sensor assemblies circuitry and silicone rubber strain relief on fasteners B 06 1004 Rev A 12 Appendix A Connectors Wiring Angle Conversion Chart Your DeepWater 420 tiltmeter uses the following connectors Bulkhead Connector male m MCBH6M B 00357 In Line Connector female on Cable Whip MCIL6F 00358 Delrin Locking Sleeve female MCDLSF 00359 Two kinds of cable are available on the cable whip 1 Neoprene SO cable with 20 AWG conductors or 2 PVC jacketed polypropylene insulated cable with 24 AWG conductors When the PVC jacketed cable is used it is joined to the neoprene cabl
16. opposite tilt direction to check this possibility The tiltmeter output should pass through 12 mA as you move it through its null level position If the tiltmeter output remains pegged at its positive or negative limit no matter how much you move it the cause may be a broken connection or short circuit where the sensor lead wires connect to the printed circuit board Remove the lid and inspect the inside of the tiltmeter Do not use an ohmmeter to check the sensor connections as doing so will B 06 1004 Rev A 5 permanently damage the sensor Visually inspect the sensor wires and the wires from the bulkhead connector and verify that the connections are properly made Look for signs of physical damage which might have resulted from excessive shock or vibration Internal fasteners were treated with LocTite in the factory to reduce the chances of their becoming loose during ordinary service When informed that the tiltmeter will be used under conditions of high shock or vibration we typically apply silicone rubber compound to selected points within the tiltmeter to hold fasteners in place and to provide strain relief in areas of high stress Figure 10 If this inspection still fails to identify the problem contact the factory for assistance or to arrange for a repair 12 Warranty and Assistance Your tiltmeter is warranted against defects in materials and workmanship for one year from the date of delivery We will repair or replace
17. r installation requirements Figures 1 and 2 Your DeepWater 420 is equipped with a 6 pin male underwater mateable neoprene connector for power and signal connections Figures 1 and 2 This connector has a depth rating of 10 000 psi 700 bars The tiltmeter comes with a mating female connector and cable whip Figure 3 The required cable length is specified when ordering All Applied Geomechanics tiltmeters are assembled calibrated and tested at our plant under strict quality standards AGI maintains complete calibration and test records of every tiltmeter built B 06 1004 Rev A 1 3 Specifications ANGULAR RANGE Standard Version Wide Angle Version 3 degrees 6 degrees span 50 degrees 100 deg span SCALE FACTOR 0 375 mA typical 6 25 mA typical RESOLUTION 0 0006 degree 2 arc seconds 0 01 degree REPEATABILITY 0 001 degree 0 02 degree LINEARITY lt 2 of full span 0 5 of full span NATURAL FREQUENCY 3 Hz 7 Hz critically damped TEMPERATURE COEF Scale factor Ks lt 0 04 C typ Ks lt 0 1 C typ Zero shift Kz 0 0002 degree C typ Kz 0 002 degree C typ TILT OUTPUT One or two 4 20 mA two wire current loops for uniaxial or biaxial measurement TIME CONSTANT T 150 msec output is proportional to 1 e where t time in seconds TEMPERATURE OUTPUT Temperature is measured with a 2500 Ohm thermistor 50 to 150 C range PO
18. red using the thermistor RT3 Temperature Measurement Your clinometer contains an internal thermistor for measuring temperature This thermistor has a negative temperature coefficient which means that its resistance decreases as the temperature goes up Its resistance at 25 C is approximately 2500 Ohms The wiring diagram for the thermistor RT3 is shown in Figure 12 When making a temperature measurement the thermistor should be powered only briefly 1 second is good to avoid self heating There are two ways to use the thermistor to measure temperature inside your tiltmeter 1 Measure the thermistor resistance directly using an ohmmeter connected to the Temperature Excitation and Temperature Out wires and then convert this resistance to temperature This conversion may be done with the help of Figures 13 14 and 15 Figure 13 graphs thermistor resistance vs the full temperature range of 50 to 70 C Figures 14 and 15 are enlargements of the regions below and above 0 C Instead of using a graph you may compute temperature from thermistor resistance with the following equation B 06 1004 Rev A 16 T B Ln RT3 C Ln RT3 A3 D Ln RT3 5 273 15 eq 1 where T is in degrees Celsius and RT3 z thermistor resistance 7 34862 04 3 38205 04 1 30862 07 D 1 21751 09 2 second method of determining temperature is to use the thermistor and fixed resistor R25 as a vo
19. s in inches mm 4 TILTMETER MOUNTING HOLES ARE 201 5 1 CLEARANCE HOLE FOR A 1 2 M4 SCREW JSE A 25 DRILL BIT TO TA 0 32 OR 10 24 PLACES T HOLE PATTE IMENSIONS ARE IN INCHES millimet Figure 5 DeepWater 420 mounting hole pattern ed 9 supply Circuiti 4 20 current loop lack e e 2 e Temperature Excitatior 215 Thermistor rell E e Temperatur ps e Temperatur irr Ir Tiltmete Cable Figure 6 Uniaxial tiltmeter wiring The current signal is measured indirectly using a shunt resistor R Ohm s Law states that V V2 IR where is current in Amperes R resistance Ohms and V and the voltages measured on opposite sides of the shunt resistor Temperature measurement is described in Appendix B Note that there is no shield in the neoprene tiltmeter cable SO 20 6 B 06 1004 Rev A Wire Color Red X power X Tilt Current Loop Black X ground Green Y power Y Tilt Current Loop White Y ground Blue Temperature Excitation Temperature Thermistor Circuit Orange Temperature Ground Figure 7 The DeepWater 420 biaxial tiltmeter has two current loop circuits for tilt measurements and one 2500 Ohm thermistor circuit for temperature measurement Rx and Ry are the shunt resistors for the X and Y channel current loops respective
20. tforms and pipelines measuring the rotational movement of dredges and other underwater machinery and tracking the pitch and roll of ships and other vessels 2 Technical Highlights Your DeepWater 420 tiltmeter senses angular movement rotation with respect to the vertical gravity vector The internal transducer is an electrolytic tilt sensor similar to a spirit level As the sensor tilts internal electrodes are covered or uncovered by a conductive fluid producing changes in electrical resistance when an AC excitation passes through the sensor The changes are measured using an AC voltage divider network The resulting signals are amplified actively rectified filtered and then converted to form a 4 20 mA current that is proportional to the measured angular rotation or tilt The uniaxial version of the tiltmeter contains one tilt sensor and one electronics module The biaxial version contains two of each Your tiltmeter also contains a 2500 Ohm at room temperature thermistor for optional temperature measurement The tiltmeter s 316 stainless steel housing is strong and corrosion resistant It is rated for operation to 3500 psi 240 bars and has been tested to failure at 7000 psi 480 bars DeepWater 420 tiltmeters are made in uniaxial and biaxial versions Both types can be ordered with standard range 3 or wide range 50 The uniaxial tiltmeters are available in longitudinal and transverse tilt configuration to better meet you
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