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Note the following: WARNING Siemens products may only be used for the applications described in the catalog and in the relevant technical documentation. If products and components from other manufacturers are used, these must be recommended or approved by Siemens. Proper transport, storage, installation, assembly, commissioning, operation and maintenance are required to ensure that the products operate safely and without any problems.
Table of contents Introduction ............................5 Purpose of the Operating Instructions .................. 5 Document history ........................ 5 Modbus RTU technology ...................... 5 Further Information ......................7 Safety notes ............................9 Installation in hazardous area....................9 Installing/mounting ..........................11 MAG/MASS 6000 IP67 or 19" ....................12 MAG 6000 I ........................
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Table of contents Output..........................43 External input ........................50 Sensor characteristics......................51 Product identity ......................... 52 A.10 Service info........................52 A.11 Display settings........................53 A.12 Flowmeter status ....................... 57 Appendix.............................. 59 Units..........................59 Units and point positioners ....................60 Modbus Coils ........................64 Error information .......................
Purpose The Operating Instructions provide all information necessary for the installation and use of the Modbus RTU add-on module (FDK-085U0234), intended for use with the Siemens Flow Instruments USM-II family of transmitters presently including SITRANS FM MAG 6000 and SITRANS FC MASS 6000.
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Introduction 1.3 Modbus RTU technology Features The SITRANS F Modbus RTU Communication modules comply with the MODBUS Serial Line Protocol. Among other things this implies a Master-Slave protocol at level 2 of the OSI model. A node (the master) issues explicit commands to one of the slave-nodes and processes responses. Slave nodes will not transmit data without a request from the master node, and do not communicate with other slaves.
The contents of these Operating Instructions shall not become part of or modify any prior or existing agreement, commitment or legal relationship. All obligations on the part of Siemens AG are contained in the respective sales contract which also contains the complete and solely applicable warranty conditions.
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Introduction 1.4 Further Information Modbus RTU RS 485 Operating Instructions, 03/2021, A5E00753974-AB...
Safety notes CAUTION Correct, reliable operation of the product requires proper transport, storage, positioning and assembly as well as careful operation and maintenance. Only qualified personnel should install or operate this instrument. Note Alterations to the product, including opening or improper repairs of the product, are not permitted.
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Safety notes 2.1 Installation in hazardous area Modbus RTU RS 485 Operating Instructions, 03/2021, A5E00753974-AB...
Installing/mounting This chapter describes the HW installation procedure for the add-on module on Siemens Flow Instruments USM-II transmitters. The Module can be installed into SITRANS FC MASS 6000 and SITRANS FM MAG 6000 transmitters. Note Not allowed for use in hazardous areas The Communication module is NOT allowed for use in hazardous areas.
Installing/mounting 3.1 MAG/MASS 6000 IP67 or 19" MAG/MASS 6000 IP67 or 19" The installation of the add-on module on transmitter types SITRANS FM MAG 6000 IP67, SITRANS FM MAG 6000 19", SITRANS FC MASS 6000 IP67 and SITRANS FC MASS 6000 19" is carried out as follows: 1.
Installing/mounting 3.2 MAG 6000 I MAG 6000 I The installation of the add-on module on a SITRANS FM MAG 6000 I is completed as follows: 1. Open the transmitter WARNING Electric shock Do not open the transmitter while power is on. 2.
Installing/mounting 3.3 MASS 6000 Ex d MASS 6000 Ex d WARNING Installation in hazardous area The communication module is NOT approved for use in hazardous area. The installation of the add-on module on a SITRANS F C MASS 6000 Ex d is completed as follows: 1.
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Installing/mounting 3.3 MASS 6000 Ex d 5. Remove the plate from the module bay 6. Insert the add-on module as shown. Note The label on the add-on module must face upwards and the connector outwards 7. Press the add-on module into position and connect the flat cable connector. Modbus RTU RS 485 Operating Instructions, 03/2021, A5E00753974-AB...
Connecting On the electrical termination boards for USM-II transmitters, additional input/output terminals have been reserved for add-on module functions. The numbering range of these terminals is as follows, but how many are actually used depends on the type of add-on module. Additional terminals reserved for add-on modules: •...
Connecting 4.1 Wiring Wiring Figure 4-1 Modbus USMII connection Table 4-1 Connection layout Terminal number MODBUS RTU RS485 Data + Data - Shield Note Temination Connecting 91,92 and 93,94 will add termination. This must be carried out if the device is the last on the segment.
System integration This chapter provides information on how to integrate the flowmeter in a Modbus RTU automation and control system. The chapter shows the necessary steps in order to put the system into operation. After finishing the steps, the system is ready to go into normal operation in the Modbus RTU automation control system.
System integration 5.2 Navigating the Modbus display menu Navigating the Modbus display menu 1. Power up the device. If the device has been installed correctly a new menu entry has appeared in the local user interface of the device (between the "Reset mode" and the "Service mode"...
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System integration 5.2 Navigating the Modbus display menu Table 5-1 Menu items Item Value Description Device Communica‐ 1-247 Device address [Factory setting: 1] tion Address Baud rate 1200, 2400, 4800, 9600, 19200, Communication speed 38400, 57600, 76800, 115200 [Factory setting: 19200] Parity/framing Communication parameters •...
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System integration 5.2 Navigating the Modbus display menu Modbus RTU RS 485 Operating Instructions, 03/2021, A5E00753974-AB...
Functions codes Modbus Commands Modbus addressing model The module allows R/W access to the following standard Modbus data register blocks: • Coils (ref. 0x address range) • Holding Registers (ref. 4x address range) I.e. the module will not support the other standard data register blocks: •...
Functions codes 6.2 Read coils Read coils Command messages The read coils functions (01hex x) allow the master to request information from the slave. The command message of a coil read is structured as shown below. Each row in the table compares to a byte in the message –...
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Functions codes 6.2 Read coils The data section of the response message contains a number of bits representing the status of the coils(s) that has been read from the device. The LSB of the coil status byte indicates the status of the coil.
Functions codes 6.3 Read multiple registers Read multiple registers Command messages The multiple register read functions (03hex) allows the master to request information from the slave. The command message of a multiple register read is structured as shown below. Each row in the table compares to byte in the message –...
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Functions codes 6.3 Read multiple registers The data section of the response message contains 8 upper and 8 lower bits of data for each register that has been read from the device. Table 6-6 Read multiple registers normal response messages Message byte Example Slave address...
Functions codes 6.4 Write single coil Read sensor temperature (4:03007) • Query: 1,3,11,190,0,2,166,11 (Hex 01,03,0B,BE,00,02,A6,0B) • Response: 1,3,4,189,216,115,34,251,77 (Hex 01,03,04,BD,D8,73,22,FB,4D) • Sensor temperature = −0.10569 °C Write single coil Command messages The write coil functions (05hex) allow the master to control single bits in the slave. The command message of a coil write is structured as shown below.
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Functions codes 6.4 Write single coil The new coil value is the value written to the coil. Table 6-9 Write coil normal response messages Message byte Example Slave address xxhex Function code 05hex Coil address Upper xxhex Lower xxhex New coil value Upper FFhex or 00hex Lower...
Functions codes 6.5 Write multiple registers Write multiple registers Command messages The multiple register write functions (10hex) allows the master to write data to the slaves registers. The command message of a multiple register write is structured as shown below. The initial slave address is 1.
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Functions codes 6.5 Write multiple registers The quantity value indicates how many consecutive registers were written to. Table 6-12 Write multiple coil normal response messages Message byte Example Slave address xxhex Function code 10hex Starting register Upper xxhex Lower xxhex Quantity Upper xxhex...
Run Indicator 0xFF Product Code 25 (0x19) Transmitter Code No 083H0222 Capability bits 0x01, 0xFF, 0x00 Manufacturer name Siemens Product name MASS 6000 Product major rev Product minor rev MODBUS module name MODBUS RTU MODBUS module No 0xFF MODBUS module major rev...
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Functions codes 6.7 Exception handlng If any doubts about the address that failed, "Last Coil/HoldReg ErrorAddr" can be read. This will return the faulty address. MODBUS reg‐ MODBUS ad‐ No. of Data type Description Read/ ister dress bytes write 4:00681 Word Last Coil ErrorAddr (MODBUS cmd: 1 or 5) 4:00682...
Technical specifications Table 7-1 Technical data Device type Slave Baud rates 1200, 2400, 4800, 9600, 19200, 38400, 57800 bits/sec Number of stations Recommended: max. 31 per segment without repeaters Device address range 1-247 Protocol RTU (Other Modbus protocols like ASCII, Plus or TCP/IP are not supported.) Electrical interface •...
Modbus holding registers In the following the holding registers for the USM II Modbus RTU module are described. Figure A-1 Modbus Holding Registers Memory Map • The minimum value of a writable "holding register" value can be read by adding 10000 to the address of the value.
Modbus holding registers A.2 MODBUS driver settings MODBUS regis‐ MODBUS ad‐ No. of bytes Data type Description Read / write dress 4:03023 3022 Float Totalizer 1 (customer unit 4:03025 3024 Float Totalizer 2/Batch (customer unit As defined in MODBUS register 4:02907 As defined in MODBUS register 4:02913 As defined in MODBUS register 4:02915 Table A-2...
Modbus holding registers A.11 Display settings Table A-21 Service info, MASS 6000 MODBUS regis‐ MODBUS ad‐ No. of bytes Data type Description Read / write dress 4:02701 2700 Double word Operating time (s) 4:02703 2702 Byte array USM II Error pending list See Error information (Page 66) 4:02730 2729...
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Modbus holding registers A.11 Display settings MODBUS regis‐ MODBUS ad‐ No. of bytes Data type Description Read / write dress 4:02903 2902 Byte Display line 2: • 0 = Text for line 3 • 1 = Volumeflow • 2 = Volumeflow % •...
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Modbus holding registers A.11 Display settings Table A-23 Display settings, MASS 6000 MODBUS regis‐ MODBUS ad‐ No. of bytes Data type Description Read / write dress 4:02901 2900 Byte Language: • 0 = English • 1 = Deutsch • 2 = Français •...
Appendix Units The following units are used in USMII transmitters: SITRANS FM • Volume flow: Table B-2 Volume flow units (Page 60) (default: m • Totalizers: Table B-5 Totalizer units for volume flow (Page 63) (default: m Note Unit settings on MODBUS and the display are linked Changing the MODBUS units influence the units displayed on the device and vice versa.
Appendix B.2 Units and point positioners Units and point positioners Table B-1 Massflow units Unit Description kg / s kilogram per second ton / s ton per second lb / s pound per second mg / s milligram per second g / s gram per second 05 ...
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Appendix B.2 Units and point positioners Unit Description USGPS US gallon per second USMGPS mega US gallon per second UKGPS Imperial gallon per second UKMGPS mega imperial gallon per second USkGPS kilo US gallon per second UKkGPS kilo imperial gallon per second / min cubic meter per minute ml / min...
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Appendix B.2 Units and point positioners Unit Description ML / d megaliter per day bbl / d barrel per day cubic meter per day cubic feet per day cubic inch per day USGPD US gallon per day USMGPD Mega US gallon per day UKGPD Imperial gallon per day UKMGPD...
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Appendix B.2 Units and point positioners Table B-4 Totalizer units for massflow Unit Description kilogram metric ton pound megagram gram 05-255 Reserved Table B-5 Totalizer units for volume flow Unit Description cubic meter milliliter liter hectoliter BBL42 barrels megaliter USBBL US barrels cubic meter cubic feet...
Appendix B.3 Modbus Coils Modbus Coils In the following the coils for the USM II MODBUS RTU module are described. Figure B-1 Modbus Coils Memory Map Communication settings Table B-7 Communication settings MODBUS register MODBUS address Data type Description Read/ write 0:00001 Coil...
Appendix B.5 Run indicator Error Number A list of all error numbers can be found in the relevant SITRANS FM / SITRANS FC Operating Instructions. No error is represented by 0x7F. Category • 0: Information • 1: Warning • 2: Permanent •...
Appendix B.6 CRC calculation Only the internally broadcasted flow-value is checked. The expected broadcast-rate is read at power up. If a broadcast is not received after 10 times the expected broadcast rate, the broadcast rate is re-read from the USM (it may have been changed since power up). If the broadcast rate was not changed (and the rate was not zero), the Run Indicator is set OFF.
MODBUS® RTU protocol as it defines ‘Registers’ and ‘Coils’ for all variables. A register in this context is always 16 bit long. This will prove restrictive for the parameters found in Siemens Flow products and therefore a number of approaches have been adopted to overcome this restriction.
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Appendix B.8 Float definition means that when a numerical quantity larger than a single byte is transmitted, the MOST significant byte is sent first. Table B-12 Float definition Value (decimal) IEEE FP B MSB LSB Register N Register N + 1 high high 100.0...
Glossary Cyclic Redundancy Check. Used for error-checking in Modbus RTU Modbus master A Modbus device, which is able to access data in one or more connected Modbus slaves. Modbus slave A Modbus device, which is able to respond to requests from a single Modbus master. RS232 Refers to communication standard defined by EIA/TIA-232 (Physical layer).