科隆流量计modbus通讯手册IFC 300Supplementary HandbookSignal converter withModbus interface for OPTIFLUX electromagnetic flowmeters Modbus ER 3.2.xx ( SW.REV.3.2.x )Modbus version 1.1.xSubject to change without notice. KROHNE 09 / 2008IFC 300 ModbusContent1 Importantinformation 3 2 Technicaldata 33 Connection of instruments in bus system 44 Electricalconnection 4 5 Modbus protocol 5 – 16 5.1 General 5 5.2 RTU Frame format 5 5.3 Overview of supported function 6 5.4 Device identification on the Modbus interface 6 5.5 Coilregisters 7 5.5.1 GDC Controls 7 5.5.2 Start calibration function 7 5.5.3 Counter controls 7 5.6 Inputregisters 8 5.7 Holding registers 9 –12 5.7.1 Counter parameters 9 – 10 5.7.2 Process input filter parameters 11 – 12 5.7.3 Modbus parameters 12 5.8 Calibration procedures 13 – 15 5.8.1 Zero flow calibration 13 5.8.2 Coil temperature calibration 14 5.8.3 Conductivity calibration 155.9 Diagnostics 166 Form (for copying) to accompany a returned instrument 19 1 ImportantinformationThe flow converter with the RS 485 interface card fitted, is able to communicate with an external device (PC or other suitable computer system) using the Modbus protocol. This option allows data exchange between PC or computer and single or multiple devices.The bus configuration consists of one external device as a master and one or more converters as slaves. For bus operation the device address (menu C5.8.1), baud rate (menu C5.8.2) and settings (menu C5.8.3, C5.8.4 & C5.8.5) must be set in the converter. All devices connected to the bus, must have different unique addresses but the same baud rate and settings.2 TechnicaldataInterface RS 485, galvanically isolatedBaud rate 1200, 2400, 4800, 9600, 19200, 38400, 57600 or115200 baudProtocol ModbusRTU(available as a separate document on request) Maximum participants on Bus 32 per line, master included(may be extended by repeaters)Coding NRZ bit codingAddress range Modbus: 1 (247)Transmission procedure Half duplex, asynchronousBus access Master / slaveCable Screened twisted pair cableDistances Maximum 1.2 km without repeater.(dependant on baud rate and cable specifications)Technical data of the Modbus interface (according to EIA standards)Kind of signal transmission DifferentialMaximum number of transmitter/receivers 32Maximum voltage on driver output -7 … +12 VMinimum voltage on driver output, max. load U diff > 1,5 V Maximum input current (off state) -20 … +20 μAReceiver input voltage -7 V … +12 VSensitivity of the receiver -200 … +200 mVReceiver input resistance > 12 kOhmShort circuit current of transmission < 250 mA3 Connection of instruments in bus systemsNetwork Biasing ResistorsFor proper operation of Modbus in half duplex mode in single or multi-drop communication, it is recommended that a termination resistor (typically 120 ohm) isapplied to both ends of the data line. The simplest form of termination is line-to-lineresistor across the differential input.In RTU mode the Modus protocol requires quiet periods on the communications bus for synchronisation. It is therefore important that the Modbus is not allowed to ‘float’, i.e. unreferenced to 0V, as this could lead to spurious signals due to noise pick-up. It is therefore necessary to employ biasing resistors at one point on the bus network,normally the “end”.The Modbus converter has two conditions. Default is without termination. To get theactive termination the settings of jumper X5 and X6 on Modbus board must be changed then, see below.4 ElectricalconnectionTerminals A and B of the converter are dependant on the options selected at order.Refer to the Standard Handbook of the converter for connection details.Modbus connectionsTerminals DescriptionD- Signal A (D 0)D Signal B (D 1)C- Common 0 VC Not connectedJumper settings on the Modbus printed circuit boardJumperpositionDescriptionX5 X61 -2 1 – 2with termination2 -3 2 - 3without termination 5 Modbusprotocol5.1 GeneralUsing RTU (Remote Terminal Unit) format, data is transmitted as 8 bit binary characters. There are no special characters to determine the start and end of a message frame, synchronization is achieved by a minimum silent period of at least 3.5 character times before the start of each frame transmission and a maximum silent period of 1.5 character times between characters in the same frame.5.2 RTU Frame formatThe format of the Query and Response frames vary slightly depending upon the command function. The basic form is outlined below.SilentPeriodSlaveAddressFunctionCodeRegister Start Address orByte Count when requiredNo.of.Points orData bytes when requiredCRC3.5 T 8 bits 8 bits8 bit byte count16 bit addressn × 8 bits 16 bits Silent periodAll transmissions must be preceded by a minimum silent period of 3.5×T, where T is the transmission time of a single character. This can be calculated from the baud rate e.g. at 19.2 kb no parity with 1 stop bit (10 bits), T = 520 μs.Slave addressThis is a single byte slave address which is transmitted first and must be in the range of 1-247. Address 0 is reserved for a broadcast address which all slaves should recognize, and therefore requires no response.Function codeThis is an eight bit code in the range of 1 … 255 although only 126 functions exist as the codes 129-255 represent an error condition. An error condition occurswhen the addressed slave does not accept the command, in which case it responds with the function code + 128, i.e. with its MSB set to 1.Byte countIn general this is only present in frames that are transferring data, and has a value equal to the number of bytes contained in the data field.The data field is limited to a maximum of 250 bytes.Register start addressFor a query command that requires data to be returned, this field will contain the 16 bit start address of the register (or data)to be returned. Note that the converter uses protocol addresses. Therefore the register address listed is the actual number required in the Modbus command. E.g: To access input register 30006, the register start address is 30006dec = 7536hex Number of pointsFor a query command that requires data to be returned, this field will contain the number of registers to be returned regardless of their bit size.Data bytesContains the data requested. The converter can use big endian format (MSB first) or little endian format (LSB first).CRCThis field contains a 16 bit CRC which is calculated on all the data bits of the message bytes.5.3 Overview of supported functionsThe following table shows MODBUS functions supported by RS485 interfaceFunction code hex dec Name Accessto01 01 Read Single Coil Status of calibration functions, Counter status (Start/Stop)03 03 Read Holding Register Cyclic Register04 04 Read Input Register Acyclic Register05 05 Write Single CoilCold Start, Warm Start, Error Reset, Start calibration function, Start / Stop Counter08 08 Diagnostics10 16 Writ Multiple Register Acyclic Register2B 43 Encapsulated InterfaceTransportTransparent Channel, ReadDevice Identification5.4 DeviceIdentificationThe device identification is according to the category regular according to the MODBUS Application Protocol Specification V1.1a. Function code 43 / 14 (0x2B / 0x0E).Device identification on the Modbus interfaceModbusObject IdObject name / Description Type Content converter0x00 VendorName 16 ByteASCII StringKROHNE0x01ProductCode10 ByteASCII StringCG numberproduction0x02MajorMinorRevision7 ByteASCII StringV1.1.000x03Vendor URL32 ByteASCII String0x04ProductName16 ByteASCII StringConverter0x05ModelName16 ByteASCII StringModbus0x06UserApplicationName16 ByteASCII Stringuser tag, displayed onthe header of thelocal screen5.5 CoilregistersThese function codes are used for access: 0x01 = read input coil0x05 = write single coilAbreviations in the following tablesGDC General Device Conceptcnt counter5.5.1 GDCControlsCoil address Function1000 write 1 generates a GDC cold start, write of 0 is ignored 1001 write 1 generates a GDC warm start, write 0 is ignored 1002 write 1 generates a GDC error reset, write 0 is ignored5.5.2 Start calibration functionsModbusprotocoladdressDescription SettingsConverterFct. No.2000 Zerocalibration C1.1.12001 Coil temperature calibration C1.1.8 2002 Electrode factor calibrationwrite 1 = start function0 = -read 0 = - C1.1.115.5.3 CountercontrolsModbusprotocoladdressDescription SettingsConverterFct. No.3000 Start / Stop Counter 1C3.1.8 /C3.1.93001 Start / Stop Counter 2C3.2.8 /C3.2.93002 Start / Stop Counter 3write:read:1 = start counter0 =stop counter1 = cnt is running0 = cnt is stopped C3.3.8 /C3.3.93003 ResetCounter1 C3.1.63004 ResetCounter2 C3.2.63005 ResetCounter3write:read:1 = reset counter0 = -0 = - C3.3.65.6 InputregistersMeasurement and status values are read only and can be accessed asModbus "Input Registers".Cyclic GDC objects are mapped to Modbus Registers.Also the result of a calibration procedure is accessed by an input register at Modbus Protocol Address 20000. The type are one or more float values.Function code is 04 (0x04).Modbus protocol address Description andSettingsTypeNumberofregisters30000 Flow speed [m/s] float 2 30002 Volume flow [m3/s] float 2 30004 Mass flow [kg/s] float 2 30006 Coil temperature [K] float 230008 Conductivity [S/m]This value may not be measured.Depending on register 31200.0 = off (not measured)1 = conductivity [S/m]2 = conductivity + empty pipe (S) [S/m]2 = conductivity + empty pipe (F) [S/m]float 230010 Diagnosis valueThis value may not be measured.Depending on register 31216.25 = off (not measured)31 = electrode noise [m/s]28 = flow profile [no unit]21 = linearity [no unit]8 = terminal 2 DC [Volt]9 = terminal 3 DC [Volt]float 230012 Display channel 1Represents the value on the first line of the firstmeasurement screen in SI unitsfloat 230014 Display channel 2Represents the value on the first line of the secondmeasurement screen in SI unitsfloat 230016 Operating time [s] float 2 30018 not used, returns zero float 230020 Counter 1 [m3] or [kg] doublefloat430024 Counter 2 [m3] or [kg] doublefloat430028 Counter 3 [m3] or [kg](This counter is only available for converter with IO 2)doublefloat430032 Long status sensor byte [4] 2 30034 Long status device byte [4] 2 5.7 HoldingregistersSome parameters of the device can be accessed as Modbus holding registers. These registers are mapped to acyclic GDC objects.Function code 03 (0x03) for read operations andfunction code 16 (0x10) for write operations.The holding registers are grouped into different sections:5.7.1 CounterparametersModbusprotocoladdressDescription andSettingsConverterFct. No.Type Number of registers 40000 Counter 1 function1 = sum counter2 = + counter3 = - counter0 = offC3.1.1 byte 1 40001 Measurement Cnt 121 = volume flow22 = mass flowC3.1.2 byte 1 40002Counter 2 function,1 = sum counter2 = + counter3 = - counter0 = offC3.2.1 byte 1 40003 Measurement Cnt 221 = volume flow22 = mass flowC3.2.2 byte 1 40004Counter3 function,1 = sum counter2 = + counter3 = - counter0 = offC3.3.1 byte 1 40005 Measurement Cnt 321 = volume flow22 = mass flowC3.3.2 byte 1Modbus protocol address Description andSettingsConverterFct. No.Type Number of registers41000 Low flow cutoff valueCnt 1 [m3] or [kg]C3.1.3 float 241002 Time constant Cnt 1 [s] C3.1.4 float 2 41004 Set Cnt 1 [m3] or [kg] C3.1.7 float 241006 Low flow cutoff valueCnt 2 [m3] or [kg]C3.2.3 float 241008 Time constant Cnt 2 [s] C3.2.4 float 2 41010 Set Cnt 2 [m3] or [kg] C3.2.7 float 241012 Low flow cutoff valueCnt 3 [m3] or [kg]C3.3.3 float 241014 Time constant Cnt 3 [s] C3.3.4 float 2 41016 Set Cnt 3 [m3] or [kg] C3.3.7 float 241018 Preset counter 1[m3] or [kg]C3.1.5 float 241020 Preset counter 2[m3] or [kg]C3.2.5 float 241022 Preset counter 3[m3] or [kg]C3.3.5 float 2Note: Counter 3 parameters are only available for converter with IO 2 ! 5.7.2 Process input filter parametersModbusprotocoladdressDescription andSettingsConverterFct. No.TypeNumber ofregisters 42000Flow direction0 = normal direction1 = reverse directionC1.2.2 byte 1 42001Pulse filter0 = off / 1 = onC1.2.4 byte 1 42002Noise filter0 = off / 1 = onC1.2.7 byte 1 42003Empty pipe0 = off1 = conductivity2 = conductivity +empty pipe (S)3 = conductivity +empty pipe (F)C1.3.1 byte 1 42004 Full pipe0 = off / 1 = onC1.3.4 byte 1 42005 Linearity0 = off / 1 = onC1.3.6 byte 1 42006 Gain0 = off / 1 = onC1.3.8 byte 1 42007 Coil current0 = off / 1 = onC1.3.9 byte 1 42008 Flow profile0 = off / 1 = onC1.3.10 byte 1 42009 Electrode noise0 = off / 1 = onC1.3.13 byte 1 42010 Setting of field0 = off / 1 = onC1.3.16 byte 1 42011 Diagnosis value25 = off31 = electrode noise 28 = flow profile21 = linearity8 = terminal 2 DC9 = terminal 3 DCC1.3.17 byte 1Modbus protocol address Description andSettingsConverterFct. No.TypeNumber ofregisters43000 Limitation low [m/s] C1.2.1 float 2 43002 Limitationhigh[m/s] C1.2.1 float 2 43004 Time constant [s] C1.2.3 float 2 43006 Pulse width [s] C1.2.5 float 2 43008 Pulse limitation [m/s] C1.2.6 float 2 43010 Noise level [m/s] C1.2.8 float 2 43012 Noise suppression C1.2.9 float 2 43014 Low flow cuttoff value [m/s] C1.2.10 float 2 43016 Limit empty pipe [S/m] C1.3.3 float 2 43018 Limit full pipe [S/m] C1.3.5 float 2 43020 Limit flow profil C1.3.11 float 2 43022 Limit electrode noise [m/s] C1.3.14 float 2 43024 Zero point [m/s] C1.1.1 float 2 43026 Coil resistance Rsp, 20 [Ohm] C1.1.7 float 2 43028 Coil temperature calpoint [K] C1.1.8 float 2 43030 Coil resistance calpoint [Ohm] C1.1.8 float 2 43032 Electrode factor EF [m] C1.1.11 float 2 43034 Conductivity calpoint [S/m] C1.1.11 float 2 43036 Conductivity calpoint [S/m] C1.1.11 float 2 5.7.3 ModbusparametersModbusprotocoladdressDescription andSettingsConverterFct. No.TypeNumber ofregisters 50000Baud rate1200 / 2400 / 3600 / 4800 / 9600 /19200 / (default) / 38400 / 57600 /115200C5.8.2 ulong 2 50002 Slave address C5.8.1 byte 1 50003 Parity0 = even parity (default)1 = odd parity3 = no parityC5.8.3 byte 1 50004Data format1 = big endian2 = little endianC5.8.4 byte 1 50005Stop bits1 = 1 stop bit (parity is used)2 = 2 stop bits (parity is not used)C5.3.6 byte 25.8 Calibrationprocedures5.8.1 Zero flow calibration5.8.2 Coil temperature calibration5.8.3 Conductivity calibration5.9 DiagnosticsThe Modbus interface supports the diagnostic function defined by the Modbusapplication protocol specification.Function code is 08 (0x08).Sub - function codehex dec Name00 00 Return query data 01 01 Restart communication option 04 04 Force listen only mode 0A 10 Clear counters 0B 11 Return bus message count 0C 12 Return bus communication error count 0D 13 Return bus exception count 0E 14 Return slave message count 0F 15 Return slave no response count 10 16 Return slave NAK count (counter not used) 11 17 Return slave busy count (counter not used) 12 18 Return bus character overrun count Notice6 Form (for copying) to accompany a returned instrument。
