WAGO 2857-570/024-001 Скачать руководство пользователя страница 62

Страница: 62 / 120

2857-570/024-001

Planning

Product manual | Version: 2.0.0
3-Phase Power Measurement Module, 1 A

1-Phase Power Measurement with N-Conductor; with voltage transformer

Please observe the following:

• System voltages: > 300 V.
• Maximum terminal voltage: u

< 300 V.

• Connection terminal N on the product is reference potential for all voltage inputs.

Figure 23: 1-Phase Power Measurement with N-Conductor; with voltage transformer

Содержание 2857-570/024-001

Страница 1: ...Product manual Version 2 0 0 Signal Conditioner 3 Phase Power Measurement 1 A 2857 570 024 001 WAGO...

Страница 2: ...sure the accuracy and completeness of this documentation However as errors can never be fully excluded we always appreci ate any information or suggestions for improving the documentation E Mail docum...

Страница 3: ...ace X1 IN and X2 OUT 16 3 3 4 Configuration interface Config 17 3 3 5 Supply Connection POWER 17 3 3 6 Memory Card Slot SD for Micro SD Cards 18 3 3 7 Functional Earth Connection 18 3 4 Indicators 18...

Страница 4: ...Data Security 52 5 2 Aids 53 5 3 Requirements for Accessories 53 5 4 Voltage Measurement 54 5 5 Current Measurement 55 5 6 Power Measurement 56 5 6 1 Power Measurement in 4 Wire 3 Phase Networks 58 5...

Страница 5: ...ule 1 A 12 Decommissioning 106 12 1 Disposal and Recycling 106 13 Appendix 107 13 1 Installation Regulations Specified by Approvals 107 13 2 Application Example 109 13 3 Examples of CSV Files 109 13 3...

Страница 6: ...roper Use Improper use of the product is not permitted Improper use occurs especially in the follow ing cases Non observance of the intended use Use without protective measures in an environment in wh...

Страница 7: ...be operated within the scope of the approval 1 2 Typographical Conventions Number Notation 100 Decimals Normal notation 0x64 Hexadecimals C notation 100 0110 0100 Binary In single quotation marks Nib...

Страница 8: ...nd source of hazard Indicates a potentially hazardous situation which if not avoided could result in death or serious injury Action step to reduce risk CAUTION Type and source of hazard Indicates a po...

Страница 9: ...roduct documentation The and TM symbols are omitted hereinafter The trademarks are listed in the Appendix 8 Protected Rights 113 Subject to Change The instructions guidelines standards etc in this man...

Страница 10: ...Power Supply For non hazardous active voltage per EN UL IEC 61010 1 SELV PELV power sup plies shall be used Connecting impermissible current or frequency values may destroy the products Grounding Prot...

Страница 11: ...amage that may have occurred dur ing shipping Do not put the product into operation in the event of mechanical damage 2 4 Thermal Safety The temperature inside the additional enclosure must not exceed...

Страница 12: ...such as voltage and current reactive apparent and active power energy consumption power factor phase angle and frequency Also harmonic analysis is possible for a selectable phase up to the 41st harmo...

Страница 13: ...ry Card Slot SD for Micro SD Cards 18 4 Voltage measurement inputs 8 Measurement Inputs 14 5 Switch output DO 8 Switch Output DO and S0 Interface 15 6 Supply connection POWER 8 Supply Connection POWER...

Страница 14: ...8 2 Spring contact for functional ground 8 Functional Earth Connection 18 See also 2 Installation and Removal 68 2 Functional Earth Connection 18 3 3 Connectors 3 3 1 Measurement Inputs Current Measur...

Страница 15: ...inputs Up to four wires of the network to be measured are connected here Figure 5 Measurement inputs for voltage measurement Position Designation Connection Description 1 Test slot for associated Push...

Страница 16: ...ltaneously To read out the energy values switch output DO can be configured as an S0 interface with the Interface Configuration Software However the same DO and GND connec tions are used 3 3 3 Modbus...

Страница 17: ...e the power measurement module for visualizing measured values as the power is measured and for firmware updates an engineering PC with the Interface Con figuration Software is used Communication via...

Страница 18: ...nt module A push push mechanism locks the memory card in the housing Figure 10 Memory card slot 3 3 7 Functional Earth Connection The functional earth connection is established automatically via the D...

Страница 19: ...ction ERR LED is illuminated Group error message 3 5 Circuit Diagram Figure 11 Schematic Circuit Diagram The areas Measurement value acquisition configuration interface SD controller Modbus RTU and Po...

Страница 20: ...ue Number of inputs 3 voltage measurement inputs 4 differential current measurement inputs Voltage measurement range rms AC 2 Phase voltage ULx N Line to line voltage ULx Ly End of Voltage measurement...

Страница 21: ...0 V Isolation type Impedance and Supplementary Insulation Overvoltage category III 3 The system voltage is derived from the line to neutral voltage for common mains supply systems and is used for dete...

Страница 22: ...on Line neutral conductor voltage 600 VAC Overvoltage category III 4 See 8 Overview Common Mains Supply Systems and Line Voltages 72 3 6 4 Measured Variables Table 8 Technical Data Measured Variables...

Страница 23: ...o 41st harmonic Current rms Voltage rms HD THD Current HD THD Voltage Measurement inaccuracies Voltage 5 0 3 of measurement range final value max value Current 0 5 of measurement range final value max...

Страница 24: ...the mechanical connection capacity of the clamp ing points Table 10 Technical Data Wiring Expected Environmental Temperature for Connecting Cables Use in the scope Temperature of the connecting cables...

Страница 25: ...ith the Low Voltage Directive through application of the following standards Low Voltage Directive UL OrdLoc Standard Electrical equipment for measurement control and lab oratory use UL FW Version 3 3...

Страница 26: ...er depending on the network topology not all measured values are always calcu lated For more information see 8 Communication per Modbus RTU 37 Table 14 Measured Value Overview Voltage Measured Value 4...

Страница 27: ...rent L1 X X X X Min RMS current L2 X X X Min RMS current L3 X X X Arithmetic mean cur rent L1 X X X X Arithmetic mean cur rent L2 X X X Arithmetic mean cur rent L3 X X X Peak value current L1 X X X X...

Страница 28: ...L3 X Active Energy import L1 X X Active Energy import L2 X Active Energy import L3 X Active Energy export L1 X X Active Energy export L2 X Active Energy export L3 X Active Energy Total X X X X Active...

Страница 29: ...re threephase network 2 wire network sin gle phase network Phase Angle phi L1 X X X X Phase Angle phi L2 X X Phase Angle phi L3 X X X Table 20 Measured Value Overview Power Factor Measured Value 4 wir...

Страница 30: ...X Fundamental compo nent current L2 X X X Upper harmonic component current L2 1st 40th upper harmonic X X X Distortion current L2 X X X RMS voltage L2 X X X Fundamental compo nent voltage L2 X Upper...

Страница 31: ...en Upper Harmonic and Harmonic First harmonic refers to the vibration at the fundamental frequency fundamental compo nent and first upper harmonic refers the vibration at twice the fundamental frequen...

Страница 32: ...in and max RMS values for the current and voltage are also determined over a configurable time interval A reset interval can be set with parameters 24 25 and 26 This interval can be activated with par...

Страница 33: ...ntegration of power yields the level of energy for each phase The power measurement module provides the values for active reactive and apparent energy Val ues for the individual phases and an overall...

Страница 34: ...mponent for the selected phase It also provides the total harmonic distortion THD for current and voltage From the 40 upper harmonics 3 can be selected and analyzed at the same time The RMS value for...

Страница 35: ...e characteristics for the three phases are monitored by rotary field detection The direction of rotation of a motor or machine can only be deter mined when the phase sequence L1 L2 L3 at the power mea...

Страница 36: ...Tamper Detect parameters 3 4 5 for undervoltage 14 15 16 for overvoltage 17 18 19 for overcurrent 20 for Tamper Detect These states are signaled by the flashing red ERR LED and switch output DO as a...

Страница 37: ...ssing Via interface configuration software If an error occurs during the transmission an error message is sent to the sender The er ror codes could be 0x01 Illegal function unsupported Modbus function...

Страница 38: ...en in the Parity selection box 14 Click the OK button The entry Interface COM2 is created in the MODBUS master configurator dia log 15 Right click the entry Interface COM2 and select Add Modbus Slave...

Страница 39: ...busSlave PRG The program editor opens 38 Click Online Login The solution is loaded into the controller 39 Click Online Start The controller is started The value of variable rVoltageL1 is read out in t...

Страница 40: ...Voltage an dPower values is active Bit 10 Min Max Value Automatic Reset Activation Phase 3 0 Automatic deletion Min and Max Current Voltage and Power values is not acti vated Factory setting 1 Automat...

Страница 41: ...efined Rogowski coil factor must be set 1 RC70 Rogowski coil factor 0 07198 H 2 RC125 Rogowski coil factor 0 07214 H 3 RC175 Rogowski coil factor 0 07231 H Table 34 Parameter 6b Rogowski Coil Factor H...

Страница 42: ...lue Measurement Observation Interval Phase 3 Address 0x0062 Data Type UINT16 Access R W Factory setting 0x0014 0 19 not permitted 20 254 Number of half waves for measuring peak values 255 not permitte...

Страница 43: ...ect Current Threshold Value fault current Address 0x0070 Data Type FLOAT Access R W Factory setting 0 A 0 The threshold value check is deactivated 1 Current Threshold max 100000 A Table 49 Parameter 2...

Страница 44: ...Parameter 26 Min Max Value Automatic Reset Interval Phase 3 Address 0x0077 Data Type UINT16 Access R W Factory setting 0x000A Activation Parameter 2 Bit 10 required 0 65535 Interval in s Table 55 Para...

Страница 45: ...ata Type UINT16 Access W Factory setting 0x0004 2 41 Harmonic number corresponds to first to 40th upper harmonic Table 62 Parameter 34 Action of the Digital Output Address 0x009A Data Type UINT16 Acce...

Страница 46: ...ion Data Type Access Factory setting Power measurement module status information UINT16 R 0x0000 Bit 0 Transient Response Period Warning 0 OK transient response period elapsed 1 Measured values not ye...

Страница 47: ...level controller has access to a number of measured value registers via Mod bus The measured values for the energies are in the data type INTEGER all others are FLOAT All registers have a size of fou...

Страница 48: ...ower L3 var R 500 0x0028 Active Power total W R 500 0x002A Reactive Power total var R 500 0x002C Apparent Power total VA R 500 0x002E Line frequency L1 Hz R 40 0x0030 Line frequency L2 Hz R 40 0x0032...

Страница 49: ...0074 Max Active Power L3 W R 40 0x0076 Min Active Power L1 W R 40 0x0078 Min Active Power L2 W R 40 0x007A Min Active Power L3 W R 40 0x007C Max Line frequency L1 Hz R 40 0x007E Max Line frequency L2...

Страница 50: ...rh 2 kvarh R 1100 0x00BC Reactive Energy capacitive total varh 2 kvarh R 1100 0x00BE Peak Value Voltage ULx N for one phase V R 40 0x00C0 Peak Value Current ILx for one phase A R 40 0x00C2 RMS Current...

Страница 51: ...igns Offer adequate protection against direct or indirect contact Offer adequate protection against UV irradiation Restrict access to authorized personnel and may only be opened with tools Ensure the...

Страница 52: ...g is mandatory to meet technical specifications regarding measure ment accuracy Establish the connection between the cable shielding and ground po tential at the inlet of the cabinet or housing This g...

Страница 53: ...rform threat analyses To restrict access to and control of individual products and networks employ a de fense in depth mechanism in your system s security configuration Additional document White Paper...

Страница 54: ...ltage paths To protect the voltage path against short circuit and overload apply a safety fuse 0 5 A slow For applications in areas covered by UL only safety fuses having a UL approval are permitted f...

Страница 55: ...for current measurement transformers shall be ob served see Installation Regulations Specified by Approvals The transformer or coil are necessary to ensure adequate isolation from the system in case o...

Страница 56: ...o measure current and can handle up to four currents simultaneously Figure 18 Connection Example Current Measurement 5 6 Power Measurement DANGER Do not work on products while energized High voltage c...

Страница 57: ...t comply with IEC 61869 If determination of the measurement topology indicates that voltage measurement trans formers must be used the transformers must comply with the standard IEC 61869 CAUTION Use...

Страница 58: ...terminals L1 L2 L3 N and the current transformers or Rogowski coils with the current measurement inputs 3 Phase Power Measurement with N Conductor without voltage transformer Please observe the follow...

Страница 59: ...uctor with voltage transformer Please observe the following System voltages 300 V Maximum terminal voltage uLx 300 V Connection terminal N on the product is reference potential for all voltage inputs...

Страница 60: ...onductor without voltage transformer Please observe the following System voltage 600 V Mains supply voltage 400 690 V For measurements with higher voltages see 8 Special Requirements for Measure ments...

Страница 61: ...ctor without voltage transformer Please observe the following System voltage 300 V Mains supply voltage 277 480 V Connection terminal N on the product is reference potential for all voltage inputs The...

Страница 62: ...wer Measurement with N Conductor with voltage transformer Please observe the following System voltages 300 V Maximum terminal voltage uLx 300 V Connection terminal N on the product is reference potent...

Страница 63: ...Measurement in 3 Wire 3 Phase Networks To measure the voltages and currents of a 3 wire three phase network connect the four wires with connection terminals L1 L2 L3 and the current transformers or R...

Страница 64: ...2857 570 024 001 Planning 64 Product manual Version 2 0 0 3 Phase Power Measurement Module 1 A Figure 25 3 Phase Power Measurement without N Conductor without voltage transformer ARON...

Страница 65: ...transformers in an open circuit Current measurement transformers from some manufacturers must not be operated in an open circuit such use may result in dangerous exposed voltages that if touched can c...

Страница 66: ...alternating currents with harmonic content up to a frequency of 2665 Hz Overcurrent Limiting Factor FS A current transformer s overcurrent limiting factor FS indicates at which multiple of the rated p...

Страница 67: ...offers optimal protection during transport and storage Store the product in suitable packaging preferably the original packaging Only transport the product in suitable containers packaging Make sure t...

Страница 68: ...onto the DIN rail without tools 1 2 3 4 Figure 27 Mounting the product on the DIN Rail 1 Tilt the product slightly 2 Place the product with the DIN rail guide on the top edge of the DIN rail 3 Press t...

Страница 69: ...pecial conditions e g in the event of a fault or increased surrounding air temperature touching the product may cause burns Allow the product to cool down before touching it 1 2 Figure 28 Remove the p...

Страница 70: ...be ob served see Installation Regulations Specified by Approvals The transformer or coil are necessary to ensure adequate isolation from the system in case of electrical fault Electrical faults can c...

Страница 71: ...ed and fine stranded conductors can be plugged in directly into the Push in CAGE CLAMP For all other conductor types the Push in CAGE CLAMP and CAGE CLAMP must be opened with an operating tool Only on...

Страница 72: ...onnected to X1 IN und X2 OUT This is an example of how the connec tions can be assigned Connection X1 IN PLC controller or up circuit Modbus device Connection X2 OUT Down circuit Modbus device Use a p...

Страница 73: ...80 V 230 V 400 V 277 V 480 V 200 V 220 V 230 V 240 V 277 V 200 V 240 V 220 V 230 V 240 V 220 V 440 V 240 V 480 V 300 V 1 Voltage specifications with forward slash 1 Voltage specifications Voltage betw...

Страница 74: ...System volt age4 TT system TN C S sys tem IT system 347 V 600 V 380 V 660 V 400 V 690 V 347 V 600 V 400 V 690 V 600 V 1 Voltage specifications with forward slash 1 Voltage specifications Voltage betw...

Страница 75: ...ith appro priate current transformers according to the specifications Secondary voltage is a low voltage level The following fault cases can result in high voltage levels Open current path for one or...

Страница 76: ...k space 150 MB Processor 1 GHz or higher 32 bit x86 or 64 bit x64 Screen resolution 800 600 pixels Table 76 Recommended System Requirements Component Requirements Operating system Windows 10 64 bit Me...

Страница 77: ...Click Finish to conclude the installation The WAGO Interface Configuration Software G2 is installed and ready to be used 10 3 Configure Product You can use the software to configure the product either...

Страница 78: ...3 Tab Backstage Menu Item Description Settings Selects the communication serial interface Used for software updates Language Selects the display language for the software About Displays information ab...

Страница 79: ...lable until you have established the connection be tween your product and the software see Menu Bar The Settings menu item is an ex ception this menu item is available as soon as a product has been ma...

Страница 80: ...Bar The individual menu items and but tons for the general parameters are arranged here 2 Selection Area The individual buttons for the corre sponding measured value view s are located here 3 Measure...

Страница 81: ...n compatibility can be obtained from WAGO Technical Support Restore Not available for this product Dialog Settings In this dialog you can modify settings for the product Two options are available Onli...

Страница 82: ...tings can be imported into a product that is configured off line a replacement product or a product used in a sim ilar w ay for example settings Resets all settings to the factory defaults Calibration...

Страница 83: ...ured can be selected here The options are as follows L1 L2 L3 Min max values Delete A minimum or maximum value that should be deleted can be selected here It is also possible to delete all measured va...

Страница 84: ...rent transformer ratio into account Enabled disabled Current transformer ratio primary current secondary current The ratio of primary current secondary current can be entered here Min max values Under...

Страница 85: ...40 Dialog settings Phase N Table 82 Dialog settings Phase N Setting options Description User scaling Phase N Take current transformer ratio into account Enabled disabled Current transformer ratio pri...

Страница 86: ...s Date Time Setting options Description Computer Manual You can se the date and time Adoption of the computer s system time Date and time are manually set Apply Applies the changes made Connected Devi...

Страница 87: ...ce Configuration Software Product manual Version 2 0 0 87 3 Phase Power Measurement Module 1 A Figure 42 Dialog settings Energy Table 84 Dialog settings Energy Setting options Description Energy consu...

Страница 88: ...nergy import L3 Active energy export L1 Active energy export L2 Active energy export L3 Reactive energy inductive L1 Reactive energy inductive L2 Reactive energy inductive L3 Reactive energy capacitiv...

Страница 89: ...ice Address Baud Rate and Parity Each device on the bus must have a different address But The baud rate and parity must always be the same Table 85 Dialog settings Modbus Setting options Description D...

Страница 90: ...ions are as follows Even None Odd Stop bits The selection of stop bits can be selected here The options are as follows 0 5 1 2 2 5 Data format The data format can be selected here The options are as f...

Страница 91: ...ry settings Setting options Description Device settings Only the device settings are reset Calibration data re mains unaffected Calibration data Only the calibration data is reset The device settings...

Страница 92: ...s Description Trigger source The trigger source can be selected here The options are as follows Off Time controlled Event controlled Interval The trigger interval can be entered here Values for loggin...

Страница 93: ...played in the individual views In addition specific parameters can be activated deactivated or adapted here All the views are described in the cection Measured Value Views below See also 2 Starting th...

Страница 94: ...e Power Measurement Module 1 A Figure 47 Measured Value View Overview Measured Value View Phase L1 L3 There is a specific view for the measured values for each phase L1 L3 User scaling min max values...

Страница 95: ...rface Configuration Software Product manual Version 2 0 0 95 3 Phase Power Measurement Module 1 A Figure 48 Example Measured Value View Phase L1 Measured Value View Currents Voltages The specific curr...

Страница 96: ...ith the Interface Configuration Software 96 Product manual Version 2 0 0 3 Phase Power Measurement Module 1 A Figure 49 Measured Value View Currents Voltages Measured Value View Power The specific ser...

Страница 97: ...on with the Interface Configuration Software Product manual Version 2 0 0 97 3 Phase Power Measurement Module 1 A Figure 50 Measured Value View Power Measured Value View Energie In this view the diffe...

Страница 98: ...he Interface Configuration Software 98 Product manual Version 2 0 0 3 Phase Power Measurement Module 1 A Figure 51 Measured Value View Energies Measured Value View Harmonics The 40 harmonics of all th...

Страница 99: ...Measured Value View Harmonics Setting options Description Selection box for the phases The phase to be analyzed can be selected here Selection box for the voltage channel current channel Whether the v...

Страница 100: ...rate with which the measured values are read out can be entered With Export Selection of whether the measurement is started with export creation of a CSV file or without export Start With Export enabl...

Страница 101: ...various connection diagrams are displayed in this view Figure 54 Measured Value View Connection Diagram Measured Value View Information Information on the connected product is displayed in this view...

Страница 102: ...g Purposes The product is not an approved billing meter as defined in the standard for electricity me ters DIN 43856 Data logging with a Micro SD Memory Card With the data logging function the measure...

Страница 103: ...2 L3 Active power L1 L2 L3 Apparent power L1 L2 L3 Reactive power L1 L2 L3 Line frequency L1 L2 L3 Phase angle phi L1 L2 L3 cos phi L1 L2 L3 Power factor PF L1 L2 L3 Power factor LF L1 L2 L3 Maximum R...

Страница 104: ...nergy inductive Reactive energy capacitive Apparent energy Active energy L2 Active energy import Active energy export Reactive energy Reactive energy inductive Reactive energy capacitive Apparent ener...

Страница 105: ...rming Measurements Product manual Version 2 0 0 105 3 Phase Power Measurement Module 1 A Data logging inactive Saving interval 10 s Measured variables Currents rms L1 L2 L3 N Voltages rms L1 N L2 N L3...

Страница 106: ...ries and packaging Clear any data stored on electrical and electronic equipment Remove lithium ion batteries lead acid batteries or memory cards that are added to the electrical and electronic equipme...

Страница 107: ...ting Not suitable for Class 2 wiring methods Not intended for connection to Class 2 equipment Secure current transformer and route conductors so that the conductors do not directly contact live termin...

Страница 108: ...T OR DISCONNECT SD CARD WHILE CIRCUIT IS LIVE UNLESS THE AREA IS KNOWN TO BE FREE OF IGNITABLE CON CENTRANTIONS OF FLAMMABLE GASES OR VA PORS AVERTISSEMENT NE PAS BRANCHER NI D BRANCHER SD CARD PENDAN...

Страница 109: ...CSV file Snapshot Measured values Current eff L1 1 979612231 A Current eff L2 0 062213849 A Current eff L2 0 062213849 A Current eff L3 0 063112609 A Current eff N 0 008522959 A Voltage eff L1 N 269 1...

Страница 110: ...8272 A Minimum Current eff L2 0 059897725 A Minimum Current eff L3 0 060773019 A Average Current eff L1 1 980110526 A Average Current eff L2 0 062145382 A Average Current eff L3 0 063039444 A Maximum...

Страница 111: ...ve L3 5 varh Apparent energy L3 31 Wh Total active energy 71 Wh Total active energy import 71 Wh Total active energy export 0 Wh Reactive energy Total 4247 varh Reactive energy inductive Total 0 varh...

Страница 112: ...he following accessories are available for the product Accessory Arcticle number Interface Configuration Software Download at www wago com WAGO USB Communication Cable length 2 5 m 750 923 WAGO USB Co...

Страница 113: ...nce DiiA Docker and the Docker logo are trademarks or registered trademarks of Docker Inc in the United States and or other countries Docker Inc and other parties may also have trademark rights in oth...

Страница 114: ...Table 15 Measured Value Overview Current 27 Table 16 Measured Value Overview Power 27 Table 17 Measured Value Overview Energy 28 Table 18 Measured Value Overview Fundamental Frequency 29 Table 19 Meas...

Страница 115: ...in Max Value Automatic Reset Interval Phase 1 44 Table 53 Parameter 25 Min Max Value Automatic Reset Interval Phase 2 44 Table 54 Parameter 26 Min Max Value Automatic Reset Interval Phase 3 44 Table 5...

Страница 116: ...settings Buttons 82 Table 80 Dialog settings Device settings 83 Table 81 Dialog settings Phase Lx 84 Table 82 Dialog settings Phase N 85 Table 83 Dialog settings Date Time 86 Table 84 Dialog settings...

Страница 117: ...Connection Example Current Measurement 56 Figure 19 3 Phase Power Measurement with N Conductor without voltage transformer 58 Figure 20 3 Phase Power Measurement with N Conductor with voltage transfor...

Страница 118: ...settings Modbus 89 Figure 44 Dialog settings Factory settings 91 Figure 45 Dialog settings SD card 92 Figure 46 Selection Area 93 Figure 47 Measured Value View Overview 94 Figure 48 Example Measured V...

Страница 119: ...2857 570 024 001 List of Figures Product manual Version 2 0 0 119 3 Phase Power Measurement Module 1 A...

Страница 120: ...gs videos and other WAGO media are subject to copyright Distri bution or modification of the contents of these pages and videos is prohibited Furthermore the content may neither be copied nor made ava...

Результаты поиска

Содержание 2857-570/024-001

Отзывы:

WAGO 2857-570/024-001, Руководство пользователя, Страница: 62 / 120

Результаты поиска

Содержание 2857-570/024-001

Отзывы: