Modbus Installation And Operating Instructions For The .

EN - EnglishModbus Installation and operating instructionsfor the sensorsVA 500 / VA 520, VA525 und VA 550 / VA 570VA 5xx Modbus RTU Installation V1.10Page 1 of 28

I.ForewordDear customer,thank you very much for deciding in favour of the VA 500 / VA 520 / VA 525 /VA 550 /VA570. Please read this installation and operation manual carefully before mountingand initiating the device and follow our advice. A riskless operation and a correctfunctioning of the VA 500 / VA 520 / VA 525 / VA 550 / VA570 are only guaranteed incase of careful observation of the described instructions and notes.Geschäftsstelle Süd/Sales Office SouthZindelsteiner Str. 15D-78052 VS-TannheimTel.: 49 (0) 7705 978 99 0Fax: 49 (0) 7705 978 99 20Mail: info@cs-instruments.comWeb: http://www.cs-instruments.comGeschäftsstelle Nord/Sales Office NorthAm Oxer 28cD-24955 HarrisleeTel.: 49 (0) 461 700 20 25Fax: 49 (0) 461 700 20 26Mail: info@cs-instruments.comWeb: http://www.cs-instruments.comVA 5xx Modbus RTU Installation V1.10Page 2 of 28

InhalstverzeichnisII.I.ForewordII.12Table of ContentTable of ContentInstructions4Definition and abbreviation41.2References4Technical data Modbus VA 5xxVA 5xx MODBUS RTU specificationn2.1General Modbus Information2.1.1Serial transmission modes (RTU)431.12.132Installation555563.1RS485 Bus Wiring (Modbus RTU) –VA 500 / VA5203.1.1Termination VA 500 / VA 5203.1.2Bias6663.2RS485 Bus Verdrahtung (Modbus RTU) – Anschlussplan VA 550 / VA5703.2.1Termination VA 550 / VA 5703.2.2Bias777Modbus RTU communication settings84.1Accessing and changing Modbus settings84.2Modbus RTU communication settings85Modbus TCP86Modbus addressing model9786.1Function Code 3 (Read holding register)6.2Function code 16 (Write multiple registers)Modbus Holding Register910117.1Basic Values Register (1 1000)117.2Values register (1001 .1500)127.3Device settings register7.3.1Modbus Settings (2001 2005)7.3.2Display Settings (2007 2009)7.3.3Device Settings (2021 2063)222222237.4Gas names267.5MBus Register277.6Data format test register (64001 64003)277.7Unit Index table28Appendix8.1APPENDIX A - Exception codesVA 5xx Modbus RTU Installation V1.102828Page 3 of 28

1InstructionsThis manual is intended to provide instructions for the installation and use of the VA 5xxMODBUS function. The VA 5xx MODBUS function can let the MODBUS master device toread out the online measurement values.This manual is not intended to be a complete tutorial on the MODBUS RTU protocol, and itis assumed the end user already has a general working knowledge of MODBUS RTUCommunications, especially in respect of master station configuration and operation.However an overview is included in the following section to explain some of thefundamental aspects of the protocol.1.1Definition and abbreviationCRCCyclic Redundancy CheckUsed for error—checking in MODBUS RTU. See appendixModbus MasterA MODBUS device, which is able to access data in one or more connectedMODBUS slavesModbus SlaveA MODBUS device, which is able to respond to requests from asingle MODBUS masterModbus AddressThroughout this document the following notation is used toaddressMODBUS RTU registers see chapter 8Addressing: Holding Register 1009 is addressed in messages by 1008PDUMODBUS protocol data unitADUMODBUS application data unitMBAPMODBUS application protocolRS485Refers to the 2—wire communication standard defined byEIA/TIA-485. (Physical layer)Ethernet1.21.2.3.4.ReferencesMODBUS over Serial Line Specification and Implementation Guide V1.02modbus.org 2006 Dec 20MODBUS APPLICATION PROTOCOL SPECIFICATION V1.1b modbus.org2006 Dec 28MODBUS Messaging on TCP/IP implementation Guide V1.0b2006 Oct 34Instruction manuals VA 5xxVA 5xx Modbus RTU Installation V1.10Page 4 of 28

2Technical data Modbus VA 5xx2.1VA 5xx MODBUS RTU specificationnDevice typeBaud RatesDevice address rangeElectrical InterfaceProtocolSupported function codeBroadcastStandard2.1Slave1200,2400, 4800, 9600, 19200, 38400, 57600, 115200 bps1.247RS485, 2 wireRTU3read holding register16write multiple registerNoModbus over serial line V1.02General Modbus InformationThe VA5xx Modbus module complies with the Modbus serial line protocol [Reference 1].Among other things, this implies a master-slave protocol at level 2 of the OSI model. Onenode (the master) issues explicit commands to one of the ,,sIave"-nodes and processesresponses. Slave nodes will not transmit data without a request from the master node, anddo not communicate with other slaves.Modbus is a mono master system, which means that only one master can be connectedat the time.2.1.1Serial transmission modes (RTU)The VA 5xx Modbus mode support only one serial transmission modes; the RTUmode. The transmission mode defines the bit contents of message fieldstransmitted serially on the line. It determines how information is packed into the messagefields and decoded.The transmission mode and serial port parameters must be the same for all devices on aModbus serial line.RTU mode Modbus Application Data Unit (ADU) frame is shown below, and is valid forboth requests and responses.Slave addressFunction codeDataCRC1 byte1byte0 up to 252 byte(s)2 bytesTable 1Further details of the Modbus protocol can be found in Reference 1 and 2.VA 5xx Modbus RTU Installation V1.10Side 5 of 28

3Installation3.1 RS485 Bus Wiring (Modbus RTU) –VA 500 / VA520 / VA 525MasterR680R 120R 680RTerminierung / BiasTABCommonTRSlave 1TRSlave nPin 2Pin 4Pin 3Connection plug AVA 500 / VA 520 / VA 5253.1.1 Termination VA 500 / VA 520 / VA 525Note: In case the VA 500 / VA 520 / VA 525 is the last device in the RS485 network then a terminationis required. To be done either witha.) Internal DIP Switchb.) 120R between (between Pin 2 and Pin 4) of connector plug A3.1.2 BiasIn order to avoid undefined bus levels, at any location on the bus, a bias network, one resistor to VCC(Modbus A) as well as to GND (Modbus B), has to be used.VA 5xx Modbus RTU Installation V1.10Side 6 of 28

RS485 Bus Verdrahtung (Modbus RTU) – Anschlussplan VA 550 / VA5703.2MasterRTABCommonTRTSlave 1RSlave nPin 3Pin 2Pin 1Connection plug X2VA 550 / VA 5703.2.1Termination VA 550 / VA 570In case the VA 550 / VA 570 is the last device in the RS485 network then a termination with 120Rbetween (between Pin 1 and Pin 3) at connector X2 is necessary.3.2.2 BiasIn order to avoid undefined bus levels, at any location on the bus, a bias network, one resistor to VCC(Modbus A) as well as to GND (Modbus B), has to be used.Bus cable:Only cables according to the recommendations of EIA 485 standard should be used. Amaximum of 64 devices may be connected to one segment. The bus cable must be laid ata distance of at least 20 cm from other cables. It should be laid in a separate, conductive,and earthed cable trunking. It must be ensured that no potential differences occur betweenthe individual devices on the bus.3.3Impedance:Cable capacity:Cable diameter:Cross section:Loop resistanceScreening:Cable specification:135 -165 Ohm @ 3 to 20 Mhz 30pF/m 0.64 mm 0.34 mm2, conforms to AWG 22 110 Ohm per kmCu shielding braid or shielding braid and shielding foilVA 5xx Modbus RTU Installation V1.10Side 7 of 28

4Modbus RTU communication settingsBefore communication with the master, baudrate, address, and framing must be defined4.1Accessing and changing Modbus settingsThe Modbus communication settings could be changed by using either the PC service software fromCS Instruments or by sensors with display in the Modbus setup menu.Note:It is recommended NOT to use the default address in a multi-slave network. It is of greatimportance to ensure at the time of the procedure of device addressing, that thereis not two devices with the same address. In such a case, an abnormal behaviour of thewhole serial bus can occur, the master being then in the impossibility to communicate withall present slaves on the bus.4.2Modbus RTU communication settingsDevice typeBaud RatesDevice address rangeElectrical InterfaceProtocolSupported function codeBroadcastStandard5Slave1200,2400, 4800, 9600, 19200, 38400, 57600, 115200 bps1.247RS485, 2 wireRTU3read holding register16write multiple registerNoModbus over serial line V1.02Modbus TCPModbus communication requires the establishment of a TCP connection between a client (e.g. PC)and the sensor. The TCP port 502 reserved for Modbus is normally used for communication. However,the user can also configure a different port number.If a firewall is arranged between sensor and client, it must be ensured that the configured TCP port isenabled.VA 5xx Modbus RTU Installation V1.10Side 8 of 28

6Modbus addressing modelThe VA 5xx RS485 Modbus allows read/write access according chapter 8Not defined registers are not accessible / not supported.Byte Order:The size of each Modbus-register is 2 Byte. For a 32 bit value two Modbus register will be read out bythe VA 5xx. Accordingly for a 16bit Value only one register is read.Data format VA 5xx:Single Word18 Data OrderA (AB)B (BA)Double WordHByte LByte00121. Byte00122. Byte12Big endian00Little endianHWordLWordHByte LByte HByte LByte29235175522 AE415652Data Order 1.Byte 3.byte564152AE4.Byte52 Big endianAE Little endian5641For verification of a correct data format please read out register 64000 or 64004.Result should be:Register 64000: Long Integer Value 1 000 000Register 64002: FloatValue 1 000 000.06.1Function Code 3 (Read holding register)General exceptions: Requesting less than 1 or more than 125 registers Exception 3 (Illegal data value) Requesting more than max. message size (27 registers) Exception 2(Illegal data address) Requesting data out of defined range of registers chapter 8 Exception 2 (Illegal data address)Application exceptions: Application errors Exception 4 (Slave device error)Holes/register alignment: The read command always returns data if no exception is given. Badstart/end alignment will result in only parts of the data item being read.VA 5xx Modbus RTU Installation V1.10Side 9 of 28

6.2Function code 16 (Write multiple registers)In general, only status register (register 2001 – 2064) are writable.General exceptions: Writing less than 1 or more than 63 registers Exception 3 (Illegal data value) If Byte Count is not exactly 2 times NoOfRegisters Exception 3 (Illegal data value) Exceeding max. message size (27 registers) Exception 2 (Illegal data address) Writing data out of defined register range chapter 8 Exception 2 (Illegal data address)Application exceptions: Application errors Exception 4 (Slave device error) Application errors include writing to ReadOnIy holding registersHoles / register alignment: If start-address is not the start of a mapped holding register Exception 2 (Illegal data address) Writing to holes is allowed (ie ignored - and no exception occurs) — except forthe condition described aboveVA 5xx Modbus RTU Installation V1.10Side 10 of 28

7Modbus Holding Register7.1Basic Values Register (1 1000)ModbusRegisterModbusAddressNo.ofByteData TypeDefaultSettingReadWrite104UInt32Serial Number0R324UInt32Software Version0Rsprintf(str,"%u.%02u",hw 16,hw&0xffff);544UInt32Hardware Version0Rsprintf(str,"%u.%02u",hw 16,hw&0xffff);764UInt320R984UInt32Production Date0RUnix Time11104UInt32Calibration Date0RUnix Time13124UInt32Ordering 32Atex Number0R21204UInt32Curve Version0R23228StringBrand ard0R31304DwordVariantxR33328StringCompany NamexR37364DwordxRsprintf(str,"%u.%02u",hw 16,hw&0xffff);39384DwordxRsprintf(str,"%u.%02u",hw n(if available)OptionBoardSoftwareVerision(falls verfügbar)VA 5xx Modbus RTU Installation V1.10Unit /CommentValue in secondssprintf(str,"%u.%02u",hw 16,hw&0xffff);0 NoLock, 1 DiameterLock, 2 CounterLock, 3 RefConditionsLockBit Mask0 no option1 4-20mA2 Ethernet4 Mbus8 ProfiBus16 SDI32 Pressure64 DirectionSide 11 of 28