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Operating manual

ELX3351

1-channel analog input terminal for strain gauge, 16 bit, Ex i

1.3.1
2019-01-15

Version:
Date:

Summary of Contents for ELX3351

Page 1: ...Operating manual ELX3351 1 channel analog input terminal for strain gauge 16 bit Ex i 1 3 1 2019 01 15 Version Date...

Page 2: ......

Page 3: ...potential separation 23 3 6 5 ELX3351 Contact assignment 24 4 Basic function principles 26 4 1 EtherCAT basics 26 4 2 Basic principles of strain gauge technology 26 5 Parameterization and programming...

Page 4: ...ction of process data 54 5 5 2 Default process image 55 5 5 3 Variants Predefined PDO 57 5 5 4 Sync Manager 58 5 6 ELX3351 Object description and parameterization 59 5 6 1 Restore object 59 5 6 2 Conf...

Page 5: ...a diagrams and descriptions in this documentation Trademarks Beckhoff TwinCAT EtherCAT EtherCAT P Safety over EtherCAT TwinSAFE XFC and XTS are registered trademarks of and licensed by Beckhoff Automa...

Page 6: ...d specialists in control automation and drive engineering who are familiar with the applicable national standards Description of instructions In this documentation the following instructions are used...

Page 7: ...gramming added 1 2 0 Connection extended with sensor display Chapter Configuration of ELX terminals in Bus Terminal block updated Chapter Identification of ELX terminals updated Technical data updated...

Page 8: ...ed otherwise e g in the documentation Associated and synonymous with each revision there is usually a description ESI EtherCAT Slave Information in the form of an XML file which is available for downl...

Page 9: ...ckhoff Traceability Number BTN In addition each ELX terminal has a unique Beckhoff Traceability Number BTN Ex marking The Ex marking can be found at the top left on the terminal II 3 1 G Ex ec ia Ga I...

Page 10: ...Foreword ELX3351 10 Version 1 3 1 Fig 2 ELX9012 with date code 32180005 and Ex marking...

Page 11: ...sistor bridge or load cell from hazardous areas Zone 0 20 and 1 21 The terminal can be connected in 4 or 6 wire technology The ratio between the bridge voltage UD and the supply voltage UR is determin...

Page 12: ...n sensor Current consumption power contacts min 20 mA dependent on sensor Special features self calibration dynamic filters freeze Bit width in the process image 32 bit Electrical isolation 1500 V E B...

Page 13: ...vices from hazardous areas The intended field of application is data acquisition and control tasks in discrete and process engineering automation taking into account explosion protection requirements...

Page 14: ...als may only be unplugged or removed from the bus terminal sys tem if all supply voltages have been switched off or if a non explosive atmosphere is ensured The connections of the ELX9560 power supply...

Page 15: ...cts of any kind into the interior of the housing e g through the ventilation slots in the housing Use only the openings provided in the housing front and appropriate tools to actuate the spring loaded...

Page 16: ...right of an ELX9560 nor to the left of any ELX signal terminal The last terminal of each ELX segment is to be covered by an ELX9012 bus end cover unless two ELX9410 power supply terminals are install...

Page 17: ...pply terminal Fig 8 Invalid arrangement missing ELX9560 power supply terminal Fig 9 Invalid arrangement terminal that does not belong to the ELX series within the ELX terminal segment Fig 10 Invalid a...

Page 18: ...When configuring the ELX terminal segment please note the maximum available output current of the ELX9560 power supply terminal in accordance with the specified technical data If required an addition...

Page 19: ...through convection The direction indication down corresponds to the direction of positive acceleration due to gravity Minimum distances Observe the following minimum distances to ensure optimum conve...

Page 20: ...tach the fieldbus coupler to the mounting rail 2 The bus terminals are now attached on the right hand side of the fieldbus coupler Join the compo nents with tongue and groove and push the terminals ag...

Page 21: ...realized by joining the components The six spring contacts of the E Bus deal with the transfer of the data and the supply of the Bus Terminal electronics The power contacts deal with the supply for t...

Page 22: ...onded ultrasonically welded conductors Note Ultrasonically bonded conductors It is also possible to connect the Standard Terminals with ultrasonically bonded ultrasoni cally welded conductors In this...

Page 23: ...rmi nal Wider screwdrivers can damage the terminal points All other ELX terminals ELXxxxx Wire size width single core wires 0 08 2 5 mm2 Wire size width fine wire conductors 0 08 2 5 mm2 Wire size wid...

Page 24: ...me No 1 not implemented UD 2 input measuring voltage difference voltage of bridge UR 3 input reference voltage supply voltage at bridge UV 4 output supply voltage for bridge 5 not implemented UD 6 inp...

Page 25: ...Color Meaning Run green These LED indicates the terminal s operating state off State of the EtherCAT State Machine INIT initialization of the terminal flashing State of the EtherCAT State Machine PREO...

Page 26: ...suring transducer interrogator The commonest principle in the industrial environment is the electrical strain gauge There are many common terms for this type of sensor load cell weighbridge etc Struct...

Page 27: ...e strain gauge in the Wheatstone bridge arrangement UD UV R1 R2 R3 R4 R0 R usually has a positive sign in the case of elongation and a minus sign in the case of compression A suitable measuring instru...

Page 28: ...ion to a 350 measuring bridge this means a measuring error of 0 1 Fig 21 4 wire connection This can be remedied by a 6 wire connection in particular for precision applications Fig 22 6 wire connection...

Page 29: ...c data Please enquire to the sensor manufacturer regarding the exact characteristic data Nominal load Emax Maximum permissible load for normal operation e g 10 kg Nominal characteristic value mV V The...

Page 30: ...quate for the respective application Also the classes differ in certain error limits related to non repeatability creep TC Accuracy class according to PTB The European accuracy classes are defined in...

Page 31: ...individual bridge resistors must not fall below the minimum value of 300 The individual strain gage bridges do not require safe isolation in accordance with the requirements of IEC 60079 11 and must b...

Page 32: ...sives Hysteresis If even elongation and compression of the load cell take place then the output voltage does not follow exactly the same curve since the deformation of the strain gauge and the carrier...

Page 33: ...ternal bridge supply is not permitted The change of the quotient of the differential and reference voltages corresponds to the relative force acting on the load cell The quotient is converted into a w...

Page 34: ...sistance must be observed Fig 26 Parallel connection with ELX3351 Load cell signals have a low amplitude and are occasionally very sensitive to electromagnetic interference Considering the typical sys...

Page 35: ...depending on its settings can adopt the characteristics of a Finite Impulse Response filter FIR filter or an Infinite Impulse Response filter IIR filter The filter is activated by default as 50Hz FIR...

Page 36: ...an be understood to be a moving average value calculation after a low pass filter Fig 29 Step response of the IIR filter Note Filter and cycle time If the FIR filters 50 Hz or 60 Hz are switched on th...

Page 37: ...tion that is permissible during this time without filter switching occurring Example The dynamic filter is to be adjusted in such a manner that a maximum slope of 0 5 digits per 100 ms 5 digits per se...

Page 38: ...Nominal load of the sensor element 0x8000 24 60 AS Scaling factor e g factor 1000 for rescaling from kg to g 0x8000 27 60 G Acceleration of gravity in m s 2 default 9 80665 ms s 2 0x8000 26 60 Gain 0x...

Page 39: ...n the gravitation the Earth s gravitational force acceleration due to gravity at the place of installation of the scales In general acceleration due to the gravitational pull of the earth at the place...

Page 40: ...ting In the following example recorded with TwinCAT Scope2 a 15 kg load cell is suddenly unloaded and loaded with 547 g SteadyState is subject to a window time from 100 ms and a tolerance of 8 g 15 kg...

Page 41: ...h the scales unloaded then with a defined load on the scales The ELX3351 automatically calculates the existing sensor characteristic values from the measured values Sequence 1 Perform a CoE reset with...

Page 42: ...and FB00 03 must contain 0 after execution Fig 35 Loading with reference load command 0x0102 in CoE object 0xFB00 01 11 Reset execute the command 0x0000 0dec on CoE object 0xFB00 01 12 Set the filter...

Page 43: ...the input stages at the two operating points zero point and final value the two measuring channels are calibrated to each other Interface for controller The self calibration takes place automatically...

Page 44: ...System Manager 02 00 This sets the tare object 0x8000 22 60 such that the display value is 0 Note Local storage The values modified during the theoretical and practical calibration are stored in a loc...

Page 45: ...ive sign This applies to both symmetrical and asymmetrical measuring spans Fig 37 Full scale value measuring span For the above examples this means Measuring range 0 10 V asymmetric unipolar full scal...

Page 46: ...re dependent to a greater or lesser degree In analog measurement technology this means that when a measured value is determined by means of an electronic circuit its deviation from the true value is r...

Page 47: ...ents between two potential points For voltage measurements a large R is used in order to ensure a high impedance For current measurements a small R is used as shunt If the purpose is resistance measur...

Page 48: ...icularly important to pay attention to the quality of this potential noiselessness voltage stability At this GND point a wire may be connected to make sure that VCM max is not exceeded in the differen...

Page 49: ...be connected according to the Beckhoff terminology as follows preferably to single ended inputs if the Supply connections of the terminal box are also to be used connect to Supply and Signal they can...

Page 50: ...device under consideration For multi channel terminals boxes with resistive direct ohmic galvanic or capacitive connection between the channels the reference ground should preferably be the symmetry...

Page 51: ...se from a user perspective they all have a common characteristic after the conversion a certain digital value is available in the controller for further processing This digital value the so called ana...

Page 52: ...e synchronous or more quickly if the AI channel operates in slow FreeRun mode or more slowly e g with oversampling is then a question of the fieldbus setting and which modes the AI device supports Fo...

Page 53: ...s reference The signal delay ms s is then the interval between the applied electrical signal with a particular amplitude and the moment at which the analog process value reaches the same value A meani...

Page 54: ...System Manager becomes effective only after restarting the EtherCAT system 5 5 1 Selection of process data The process data of the ELX3351 are set up in the TwinCAT System Manager The PDOs can be act...

Page 55: ...ption The predefined configurations can be selected in the process data overview Therefore the function is available only if the ESI XML files are saved in the system downloadable from the Beckhoff we...

Page 56: ...EAL format of IEC 559 A REAL number single precision is defined as follows See also Beckhoff InfoSys TwinCAT PLC Control standard data types According to IEC 61131 this 32 bit variable can be linked d...

Page 57: ...ning starts tare stops the measurement switches the automatic self cali bration off starts the self calibra tion immediately 5 5 3 Variants Predefined PDO Floating point representation of the load The...

Page 58: ...ation in progress Index 0x6000 09 61 Steady State Index 0x6000 10 61 TxPDO Toggle 0x1A01 d efault 0x1A02 0x1A04 0x1A05 0x1A06 0x1A07 4 0 RMB Value INT32 Index 0x6000 11 61 Value 0x1A02 0x1A01 0x1A04 0...

Page 59: ...double click on the respec tive object or via the Process Data tab allocation of PDOs Please note the following gen eral CoE notes when using manipulating the CoE parameters Keep a startup list if co...

Page 60: ...3216dec 1 0 8000 22 Tare Process data value offset REAL32 RW 0x00000000 0dec 0 0 8000 23 Rated output Nominal characteristic value of the sensor element in mV V REAL32 RW 0x40000000 1073741824dec 2 0...

Page 61: ...0dec 6000 08 Calibration in progress Calibration is running The process data show the last valid measured value BOOLEAN RO 0x00 0dec 6000 09 Steady state BOOLEAN RO 0x00 0dec 6000 10 TxPDO Toggle The...

Page 62: ...rd con tains the CoE profile used 5001 The Hi Word con tains the module profile according to the modular de vice profile UINT32 RO 0x01681389 23597961dec Index 1008 Device name Index hex Name Meaning...

Page 63: ...0x7000 RMB out puts entry 0x05 Tara OCTET STRING 10 RO 0x7000 05 1 1600 06 Subindex 006 6 PDO Mapping entry 3 bits align OCTET STRING 10 RO 0x0000 00 3 1600 07 Subindex 007 7 PDO Mapping entry 8 bits...

Page 64: ...x0E Sync error OCTET STRING 10 RO 0x6000 10 1 Index 1A01 RMB TxPDO Map Value INT32 Index hex Name Meaning Data type Flags Default 1A01 0 RMB TxPDO Map Value INT32 PDO Mapping Value INT32 UINT8 RW 0x01...

Page 65: ...ynchronous with SM 2 event is supported Bit 2 3 01 DC mode is supported Bit 4 5 10 Output shift with SYNC1 event only DC mode Bit 14 1 dynamic times measurement through writing of 0x1C32 08 UINT16 RO...

Page 66: ...of 0x1C32 08 or 0x1C33 08 UINT16 RO 0x0001 1dec 1C33 05 Minimum cycle time as 0x1C32 05 UINT32 RO 0x000186A0 100000dec 1C33 06 Calc and copy time Time between reading of the inputs and availability of...

Page 67: ...1 3 1 Index F010 Module list Index hex Name Meaning Data type Flags Default F010 0 Module list Max subindex UINT8 RW 0x02 2dec F010 01 SubIndex 001 RMB UINT32 RW 0x00000172 370dec F010 02 SubIndex 00...

Page 68: ...of certification are marked by this sign 2 UL certification according to UL508 with limited power consumption The current consumed by the de vice is limited to a max possible current consumption of 4...

Page 69: ...onents there Beckhoff Headquarters Beckhoff Automation GmbH Co KG Huelshorstweg 20 33415 Verl Germany Phone 49 0 5246 963 0 Fax 49 0 5246 963 198 e mail info beckhoff com Beckhoff Support Support offe...

Page 70: ...rangement missing ELX9012 bus end cover 18 Fig 12 Installation position and minimum distances 19 Fig 13 Attaching on mounting rail 20 Fig 14 Disassembling of terminal 21 Fig 15 Standard wiring 22 Fig...

Page 71: ...agram signal delay step response 53 Fig 44 Diagram signal delay linear 53 Fig 45 ELX3351 process data selection in the TwinCAT System Manager 54 Fig 46 ELX3351 selection Predefined PDO Assignment 55 F...

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