Light Curtain with E-Stop Safety Function
Contents
1. Safety Function Documents GSR Safety Function Light Curtain Product GSR DI Light Curtain with E Stop Safety Rating PLe Cat 4 to EN ISO 13849 1 2008 GSR Light Curtain Safety Function Verification and Validation Checklist GENERAL MACHINERY INFORMATION Machine Name Model Number Machine Serial Number Customer Name Test Date Tester Name s Schematic Drawing Number Guardmaster Safety Relay Model Safety Wiring and Relay Configuration Verification aap yey ranicwedetocmendithstemaie SCS e Wanye rey orman sennosareoneasamenea Normal Operation Verification The safety relay system properly responds to all normal Start Stop Estop and Reset Commands Initiate a Start Command Both contactors should energize for a normal machine run condition Verify proper machine status indication and safety relay LED indication Initiate a Stop Command Both contactors should de energize for a normal machine Stop condition Verify proper machine status indication and safety relay LED indication While Running interrupt the light curtain Both contactors should de energize and open for a normal safe condition Verify proper machine status indication and safety relay LED indication Repeat for all light curtains While Stopped interrupt the light curtain initiate a Start Command Both contactors should remain de energized and open for a a normal safe condition Verify proper machine status indication and safety relay LED indication2. 4 to EN ISO 13849 1 2008 Calculation of the Performance Level cont The E Stop safety function is represented below INPUT LOGIC outpuT E Stop 1 B1 E1 NHP Safety Reference Guide gt Safety Function Documents GSR 6B 72 Safety Function Documents GSR Safety Function Light Curtain Product GSR DI Light Curtain with E Stop Safety Rating PLe Cat 4 to EN ISO 13849 1 2008 Calculation of the Performance Level cont E Stop safety Function Subsystem 3 BE Safety Contactors IPFH 1 h 2476 8 Ca j4 IMTTFd al 100 High DCava 99 High 65 fulfilled Note that the E Stop and Safety Contactors data includes MTTFd DCavg and CCF data This is because these are electromechanical devices Electromechanical devices functional safety evaluations include how frequently they are operated whether they are effectively monitored for faults and properly specified and installed SISTEMA calculates the MTTFd using B10d data provided for the contactors along with the estimated frequency of use entered during the creation of the SISTEMA project The DCavg 99 for the contactors was selected from the Output Device table of EN ISO 13849 1 Annex E Direct Monitoring The DCavg 99 for the E Stop was selected from the Input Device table of EN ISO 13849 1 Annex E Cross Monitoring The CCF value is generated using the scoring process outlined in Annex F of
3. Initiate Reset Command Both contactors should remain de energized Verify proper machine status indication and safety relay LED indication Abnormal Operation Verification The Safety Relay system properly responds to all foreseeable faults with corresponding diagnostics Light Curtain Input Tests While Running remove the Channel 1 wire from the safety relay Both contactors should de energize Verify proper machine status indication and safety relay LED indication Repeat for Channel 2 While Running short the Channel 1 of the safety relay to 24VDC Both contactors should de energize Verify proper machine status indication and safety relay LED indication Repeat for Channel 2 a While Running short the Channel 1 of the safety relay to OVDC Both contactors should de energize Verify proper machine status indication and safety relay LED indication Repeat for Channel 2 While Running short Channels 1 amp 2 of the safety relay Both contactors should de energize Verify proper machine status indication and safety relay LED indication GSR Logic Solver Tests While Running remove the single wire safety connection between two adjoining safety relays in the system All contactors should de energize Verify proper machine status indication and safety relay LED indication Repeat for all safety connections This test is not applicable for single relay circuits While Running turn the logic rotary switch on the safety relay All c
4. is called the Safety Distance and will be addressed later in this Application Note An object intruding into the light curtain field of view will stop the hazardous motion by removal of power to the motor The system cannot be reset while an object is in the field of view Once the object has left the field of view pressing and releasing the Reset button a separate action will resume the hazardous motion Pressing the E Stop button will stop the hazardous motion by removal of power to the motor Releasing the E Stop will not restart the hazardous motion Pressing the reset button after the E Stop has been reset and all faults are cleared will result in the restoration of the hazardous motion Faults at the light curtain wiring or Safety Relay will be detected before the next safety demand The safety system described in this Application Note is capable of connecting and interrupting power to motors rated up to 9A 600VAC The Safety Functions will each meet the requirements for Performance Level e Category 4 PLd Cat 4 per ISO 13849 1 and SIL3 per IEC 62061 and control reliable operation per ANSI B11 19 NHP Safety Reference Guide gt Safety Function Documents GSR 6B 65 Safety Function Documents GSR Safety Function Light Curtain Product GSR DI Light Curtain with E Stop Safety Rating PLe Cat 4 to EN ISO 13849 1 2008 Throughout this manual when necessary we use notes to make you aware of safety consideration
5. operate and maintain the MSR45E Expansion Module SensaGuard Integrated Latch Unique Coded Installation Instructions How to install commission operate and maintain the SensaGuard Touch Button and Guard Installation Instructions How to install and mount the 800Z Touch Button Zero Force Touch Buttons Family Brochure Brochure that describes all 800Z Palm Buttons MSR12T Safety Relays Installation Instructions ae configure commission operate and maintain the MSR 12T Guardmaster Safety Relay Installation Instructions 440R IN042 How to install commission operate and maintain the 440R S12R2 Safety Relays NHP Safety Reference Guide gt Safety Function Documents GSR 6B 76 Safety Function Document Disclaimer The information contained in this and any related publications is intended as a guide only Every care has been taken to ensure that the information given is accurate at time of publication Neither NHP nor any of the manufacturers portrayed in this and any related publications accept responsibility for any errors or omissions contained therein nor any misapplications resulting from such errors or omissions Risk assessments should be conducted by authorized persons The purchaser and installer are responsible for ensuring the safety system s incorporating these products complies with all current regulations and applicable standards Products are subject to change without notice and may differ from any illustration s provided All
6. products offered for sale are subject to NHP standard Conditions of Sale a copy of which is available on application NHP Safety Reference Guide gt Safety Function Documents GSR 6B 77
7. turning opening its safety contacts and removes power from the 100S contactor coils This removes 24V from the coils of the two 100S contactors whose contacts open removing power to the motor The motor will coast to a stop Stop Category 0 Two NC contacts one from each of the safety contactors are connected as part of the reset circuit The Safety Relay can be reset only if both safety contactors are in a proper de energized state The Safety Relay cannot be reset while the E Stop remains actuated or while the light curtain OSSD outputs are off Once the E Stop has been released and or the light curtain OSSD outputs turn on pressing and releasing the Reset button a separate deliberate action will resume the hazardous motion The Reset button must be pressed for more than a quarter second and less than three seconds A shorter press will be ignored a longer press will be ignored The Safety Relay checks itself for internal faults faults on its inputs and wiring and monitors the safety contactors via the contactors NC contacts in the reset circuit No single fault will result in the safety system failing to perform its safety function A single fault will be detected before the next demand on the safety system The system cannot be reset until the fault is corrected Installation Refer to the installation instruction and user manuals for guidance on installing and maintaining the different parts of this system A safety lig
8. GSR SAFETY FUNCTION DOCUMENTS Light Curtain with E Stop Lid 9 Lit VW Lit De Lit Li Lit CK gt Lit Li lt L e QW a AB wy Authorised Distributor Safety Function Documents GSR Safety Function Light Curtain Product GSR DI Light Curtain with E Stop Safety Rating PLe Cat 4 to EN ISO 13849 1 2008 Table of Contents Introduction ee D Important User Information ST Safety Function Realization 02 General Safety Information SB Setup and Wiring T Configuration er 656 Calculation ofthe Performance Level ST Verification and Validation Plan GT Additional Resources 6 63 NHP Safety Reference Guide gt Safety Function Documents GSR 6B 63 Safety Function Documents GSR Safety Function Light Curtain Product GSR DI Light Curtain with E Stop Safety Rating PLe Cat 4 to EN ISO 13849 1 2008 Introduction This Safety Function application note explains how to wire and configure a GSR DI dual input Safety Relay to monitor both an E Stop and GuardShield Light Curtain When an object intrudes into the light curtain s field of view the E Stop is actuated or a fault is detected in the monitoring circuit the GSR DI Safety Relay de energizes the final control devices in this case a pair of 100S safety contactors E Stops are required in most applications Safety Systems requiring both a sensing device like a light curtain and E Stop combination are commo
9. ISO 13849 1 The complete CCF scoring process must be done when actually implementing an application A minimum score of 65 points must be achieved Verification and Validation Plan safety system design and development process ISO EN 13849 2 sets the requirements for verification and validation It calls for a documented plan to confirm all the Safety Functional Requirements have been met Verification is an analysis of the resulting safety control system The Performance Level PL of the safety control system is calculated to confirm it meets the Required Performance Level PLr specified The SISTEMA software tool is typically utilized to perform the calculations and assist with satisfying the requirements of ISO 13849 1 Validation is a functional test of the safety control system to demonstrate that it meets the specified requirements of the safety function The safety control system is tested to confirm all of the safety related outputs respond appropriately to their corresponding safety related inputs The functional test should include normal operating conditions in addition to potential fault inject of failure modes A checklist is typically used to document the validation of the safety control system Prior to validating the GSR Safety Relay system it is necessary to confirm the GSR Relay has been wired and configured in accordance with the Installation Instructions NHP Safety Reference Guide gt Safety Function Documents GSR 6B 73
10. afety Description When an object intrudes into the light curtain field of view the light curtain hazardous motion is stopped and prevented from restarting starting until the light curtain field of view is restored Likewise when the E Stop is pressed the hazardous motion is stopped and prevented from restarting starting until the E Stop is released Bill of Material Cat No Description GuardShield Safety Light Curtain Res 14 mm Pt Ht 640 Quantity TE PAVORO mm 64 Beams Integrated Laser Alignment l DC Micro M12 Female Straight 4 Pin PVC Cable 889D F4AC2 Yellow Unshielded 22AWG IEC Color Coded No 1 Connector 2 meter 6 56 feet DC Micro M12 Female Straight 8 Pin PVC Cable 889D F8AB 2 Yellow Unshielded 24AWG IEC Color Coded No 1 Connector 2 meter 6 56 feet 800F Push Button Metal Guarded Blue R Metal Latch Mount SOUEM GOTO 1N 0 Contact s 0 N C Contact s Standard Standard Pack Qty 1 800F 1 Hole Enclosure E Stop Station Plastic PG Twist eevee to Release 40mm Non llluminated 2 N C i Guardmaster Safety Relay 2 Dual Channel Universal mate ane Inputs 1 N C Solid State Auxiliary Outputs 100S C09ZJ23C MCS 100S C Safety Contactor 9A 24V DC 2 Setup and Wiring For detailed information on installing and wiring refer to the product manuals listed in the Additional Resources System Overview When an object intrudes into the light curtain field of view the lig
11. ht curtain provides no physical barrier between personnel and the hazardous motion The safety light curtain must be installed at a sufficient distance from the hazardous motion to ensure that an operator putting a hand through the light curtain cannot reach the hazard before it has stopped This distance is referred to as the Safety Distance The Safety Distance Ds required varies from installation to installation and therefore must be calculated for each specific application This Application Note will use the ANSI formula Ds Kx Ts Tc Tr Tom Dpf K The Standard hand speed of 63 inches per second Ts The stop time of the machine Tc The response time of the safety system Tr The response time of the presence sensing device Tbm Additional time allowed for the brake monitor if any to compensate for variations in normal stopping time Dpf the distance a Standard hand could possibly move through the light curtain before it is detected This is a fixed value based on the light curtain resolution In this Application Note the values are K 63 inches per second Ts 900ms Tc 50ms 35ms DI plus 15ms K1 K2 Tr 20ms Tbm 0 none used in this application Dpf 23 8mm I inch DS 63 x 97 1 62 11 inches The light curtain must not be mounted closer than 62 11 inches from the hazardous motion being guarded against The same calculation using EN ISO 13855 S KxT C S Minimum distance in
12. ht curtain switches off its two PNP outputs OSSDs The Safety Relay responds to this by opening its two output relays This removes 24V from the coils of the two Safety Contactors whose contacts open removing power to the motor The motor will coast to a stop Stop Category 0 The light curtain s OSSD outputs turn on once its field of view is no longer interrupted The light curtain monitors its internal circuitry and its OSSD outputs for faults When a fault in the internal circuitry or an output is detected the Light curtain responds by turning off its OSSD outputs The GSR Dl s pulse test outputs 11 and 21 are run through the two NC contacts of the E Stop to inputs S12 and 22 respectively When the E Stop is pressed these circuits are interrupted GSR DI responds by turning open its safety contacts and removes power from the 100S contactor coils This removes 24V from the coils of the two 100S contactors whose contacts open removing power to the motor The motor will coast to a stop Stop Category 0 NHP Safety Reference Guide gt Safety Function Documents GSR 6B 66 Safety Function Documents GSR Safety Function Light Curtain Product GSR DI Light Curtain with E Stop Safety Rating PLe Cat 4 to EN ISO 13849 1 2008 The GSR DI monitors the E Stop circuit for faults Loose wires shorts to 24V shorts to GND contacts failed closed and cross faults will be detected When a fault is detected the GSR DI responds by
13. ion Instructions How to install commission operate and maintain the 440R D22R2 Safety Relays Guardmaster Safety Relay Troubleshooting Guide How to troubleshoot the 440RD22R2 Safety Relays Guardmaster Expansion Relay Installation Instructions ARE aaah Dpcrateran ina ita Me ii Guardmaster Expansion Relay Troubleshooting Guide Pane als OOKAN ANC AIDAAN ie FAAEE MERA Safety Products Catalog Overview of Safety products product specifications and application examples GuardShield Type 4 User Manual How to install operate and maintain the 440L Safety Light Curtains Next Generation Guardmaster Safety Relays Functional descriptions guidance and wiring for Safety Relays ean uaan neid aeh araliaionietiuctins a elias configure commission operate and maintain MT GD2 Interlock Trojan T15 Interlock Switch Installation Instructions Serer Ons EOIIIES ON operate ana Maintain aay Safety Interlock Switches Brochure Overview of Interlock Switches Guardmaster Safety Relay SI Installation Instructions How to install configure commission operate and maintain GSR SI Safety Relays Guardmaster Safety Relays Selection Guide Overview of Guardmaster Safety Relays RightSight Photoelectric Sensor Installation Instructions How to install commission operate and maintain 42EF Photoelectric Sensors MSR42 Control Module User Manual How to install commission operate and maintain MSR42 Systems MSR45E Safety Relay Expansion Module User Manual How to install commission
14. lay LED indication machine status indication and safety relay LED indication Repeat for all light curtains While Stopped interrupt the light curtain initiate a Start Command Both contactors should remain de energized and open for a normal safe condition Verify proper machine status indication and safety relay LED indication Initiate Reset Command Both contactors should remain de energized Verify proper machine status indication and safety relay LED indication While Running interrupt the light curtain Both contactors should de energize and open for a normal safe condition Verify proper EE Abnormal Operation Verification The Safety Relay system properly responds to all foreseeable faults with corresponding diagnostics Light Curtain Input Tests While Running remove the Channel 1 wire from the safety relay Both contactors should de energize Verify proper machine status indication and safety relay LED indication Repeat for Channel 2 While Running short the Channel 1 of the safety relay to 24VDC Both contactors should de energize Verify proper machine status indication and safety relay LED indication Repeat for Channel 2 m While Running short the Channel 1 of the safety relay to OVDC Both contactors should de energize Verify proper machine status indication and safety relay LED indication Repeat for Channel 2 While Running short Channels 1 amp 2 of the safety relay Both contactors should de energize Ve
15. millimeters mm K Isa parameter in millimeters per second mm s derived from data on approach speeds of the bodyor parts of the body T is the overall stopping performance in seconds C is the intrusion distance in mm In this Application Note the values are K 1600mm per second T 970ms Machine Stopping Time Reaction time of LC Reaction time of DI and contactors K1 K2 C 8 d 14 but not less than 0 where d is the resolution of the light curtain S 1600 x 970 8 14 14 The light curtain must not be mounted closer than 1552mm approx 61 in from the hazardous motion being guarded against NHP Safety Reference Guide gt Safety Function Documents GSR 6B 67 Safety Function Documents GSR Safety Function Light Curtain Product GSR DI Light Curtain with E Stop Safety Rating PLe Cat 4 to EN ISO 13849 1 2008 Electrical Schematic 24V FERIT EESTELTEE TE ETTER TTEE S r DI 440R D22R External Switched l StopyStart Circuit Hi NHP Safety Reference Guide gt Safety Function Documents GSR 6B 68 Safety Function Documents GSR Safety Function Light Curtain Product GSR DI Light Curtain with E Stop Safety Rating PLe Cat 4 to EN ISO 13849 1 2008 Configurations The 440L Light curtain uses dip switches to configure it for different applications This application uses the Default Settings No switch changes are necessary Receiver Factory Setting
16. n The DI with its dual inputs makes this easy to implement in a single Safety Relay Important User Information Solid state equipment has operational characteristics differing from those of electromechanical equipment Safety Guidelines for the Application Installation and Maintenance of Solid State Controls publication SGI 1 1 available from your local Rockwell Automation sales office or online at http www rockwellautomation com literature describes some important differences between solid state equipment and hard wired electromechanical devices Because of this difference and also because of the wide variety of uses for solid state equipment all persons responsible for applying this equipment must satisfy themselves that each intended application of this equipment is acceptable In no event will Rockwell Automation Inc be responsible or liable for indirect or consequential damages resulting from the use or application of this equipment The examples and diagrams in this manual are included solely for illustrative purposes Because of the many variables and requirements associated with any particular installation Rockwell Automation Inc cannot assume responsibility or liability for actual use based on the examples and diagrams No patent liability is assumed by Rockwell Automation Inc with respect to use of information circuits equipment or software described in this manual Reproduction of the contents of
17. n mind that the 100S contactors are used in both safety functions so in their calculations are based on 17 520 operations per year E SE Documentahon Sahely hunctions The overall safety project Performance Level is Safety function Pedtomance Level PL e PHN 32ES This Safety System includes two Safety Functions a Light Curtain Safety Function and an E Stop Safety Function The two Safety Functions can be represented in block diagrams INPUT LOGIC OUTPUT CEEE TETTETETT ELT BRP PDP SPSS SS SS SS Pe EE Lt ee Ee Pt SS SSS Se Light Curtain lt lt a E E a a SQ GPP SSeS Ss Subsystem SUSE ee ub System 1 a a NHP Safety Reference Guide gt Safety Function Documents GSR 6B 70 Safety Function Documents GSR Safety Function Light Curtain Product GSR DI Light Curtain with E Stop Safety Rating PLe Cat 4 to EN ISO 13849 1 2008 Calculation of the Performance Level cont Light Curtain Safety Function Subsystem 1 modeled as below EH Light Curtain GuardShield 440L Type 4 Single aS MTT Fd a Light Curtain safety Function Subsystem 2 Monitoring Safety Relay GSR DI 65 fulfilled NHP Safety Reference Guide gt Safety Function Documents GSR 6B 71 Safety Function Documents GSR Safety Function Light Curtain Product GSR DI Light Curtain with E Stop Safety Rating PLe Cat
18. ontactors should remain de energized Verify proper machine status indication and safety relay LED indication Repeat for all safety relays in the system Safety Contactor Output Tests While Running remove the contactor feedback from the safety relay All contactors should remain energized Initiate a Stop Command followed by a Reset Command The relay should not restart or reset Verify proper machine status indication and safety relay LED indication NHP Safety Reference Guide gt Safety Function Documents GSR 6B 74 Safety Function Documents GSR Safety Function Light Curtain Product GSR DI Light Curtain with E Stop Safety Rating PLe Cat 4 to EN ISO 13849 1 2008 GSR Light Curtain Safety Function Verification and Validation Checklist cont GENERAL MACHINERY INFORMATION Machine Name Model Number Machine Serial Number Customer Name Test Date Tester Name s Schematic Drawing Number Guardmaster Safety Relay Model Safety Wiring and Relay Configuration Verification e ee S e Normal Operation Verification The safety relay system properly responds to all normal Start Stop Estop and Reset Commands Initiate a Start Command Both contactors should energize for a normal machine run condition Verify proper machine status indication and safety relay LED indication Initiate a Stop Command Both contactors should de energize for a normal machine Stop condition Verify proper machine status indication and safety re
19. rify proper machine status indication and safety relay LED indication GSR Logic Solver Tests While Running remove the single wire safety connection between two adjoining safety relays in the system All contactors should de energize Verify proper machine status indication and safety relay LED indication Repeat for all safety connections This test is not applicable for single relay circuits While Running turn the logic rotary switch on the safety relay All contactors should remain de energized Verify proper machine status indication and safety relay LED indication Repeat for all safety relays in the system Safety Contactor Output Tests While Running remove the contactor feedback from the safety relay All contactors should remain energized Initiate a Stop Command followed by a Reset Command The relay should not restart or reset Verify proper machine status indication and safety relay LED indication NHP Safety Reference Guide gt Safety Function Documents GSR 6B 75 Safety Function Documents GSR Safety Function Light Curtain Product GSR DI Light Curtain with E Stop Safety Rating PLe Cat 4 to EN ISO 13849 1 2008 Additional Resources For more information about the products used in this example refer to these resources Document Pub No Description Guard Locking Switch Installation Instructions How to install commission operate and maintain the 440G TZS21UPRH Guardmaster Safety Relay Installat
20. s Mode Activation Combination activates one Switch Switch Function Default Setting Description of the following modes Guard Only Start Interlock Restart Interlock 3 MPCE Monitoring Disable PN Disabled 4 Fixed Blanking Activate Disabled i Pating prancing Activate angie Beam Switches 5 amp 6 cannot be activated On at the same time Guard Only 6 Floating Blanking Activate Two Beams Set Beam Coding B Disabled pw ooo Disabled OFF Signal High Active No connection or connect normally open ON Signal Low Active Connect N C Machine Test Signal The 440R D22R2 Safety Relay DI must be configured LOGIC 2 L12 OR IN 1 AND IN 2 Configure the Safety Relay for LOGIC 2 as per the Installation Instructions publication 10000175129 ver 00 NHP Safety Reference Guide gt Safety Function Documents GSR 6B 69 Safety Function Documents GSR Safety Function Light Curtain Product GSR DI Light Curtain with E Stop Safety Rating PLe Cat 4 to EN ISO 13849 1 2008 Calculation of the Performance Level Performance Level required from the Risk Assessment is Performance Level d PLd When properly implemented the Safety Functions described here can achieve a PLe according to EN ISO 13849 1 2008 as calculated using the SISTEMA Tool Calculations are based on each Safety Function being operated once an hour 24 hours a day 365 days a year for a total of 8 760 operations a year Bear i
21. s WARNING Identifies information about practices or ciroumstances thal can cause an explosion in a hazardous environment which may lead to personal injury or death property damage or economic loss inan i Identifies information thal is critical for successtul IMPORTANT erlivation and understanding af the product ATTENTION Identifies information about practices or circumelances that can lead to personal injury or death property damage or economic loss Atfentions help you identify a hazard avoid a hazard and recognize the SHOCK HAZARD Labels may be on or inside the equipment for example a drive or motor to alert people thal dangerous voltage may be present BURN HAZARD Labels may be on or inside the equipment for example a Give or motor to alert people thal surfaces may reach dangerous temperalures General Safety Information Contact Rockwell Automation to find out more about our safety risk assessment services This application example is for advanced users and assumes that you are trained and experienced in safety system requirements IMPORTANT ATTENTION A nisk assessment should be performed to make sure all task and hazard combinations have been identified and addressed The risk assessment may require additional circuitry to reduce the risk to a tolerable level Safety circuits must take into consideration safety distance calculations which are mot part of the scope of this document Functional S
22. this manual in whole or in part without written permission of Rockwell Automation Inc is prohibited NHP Safety Reference Guide gt Safety Function Documents GSR 6B 64 Safety Function Documents GSR Safety Function Light Curtain Product GSR DI Light Curtain with E Stop Safety Rating PLe Cat 4 to EN ISO 13849 1 2008 Safety Function Realization Risk Assessment The required performance level is the result of a risk assessment and refers to the amount of the risk reduction to be carried out by the safety related parts of the control system In this Application Note the performance level required by the Risk Assessment is PLr PLe Category 4 for each Safety Function A safety system that achieves PLe Category 4 or higher can be considered control reliable Light Curtain Safety Function Part of the risk reduction process is to determine the safety functions of the machine The Safety System described in this application has two Safety Functions 1 Emergency stop initiated by intrusion into the light curtain s field of view point of operation control 2 Emergency stop initiated by actuation of an emergency push button This system executes a Stop Category 0 stop Power is removed and the motion coasts to a stop Safety Functional Requirements The light curtain must be installed at a distance from the hazardous motion such that a user cannot reach the hazard before the motion has stopped This distance
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