DATASHEETS1 Intro_eng

1、PROFIBUS-DP course,LP Elektronik GmbH,Medium-sized enterprise Realtime-Operating Systems Software-Development Hardware-Development Automation with Windows 95/NT,A short view,Contents of the course,PROFIBUS basics PROFIBUS-DP and the KRC-1 by KUKA Configuration of PROFIBUS master- und slave-systems S

2、tarting and searching of mistakes in PROFIBUS systems at the KRC-1,Why field busses?,The conventional communication,Control unit,Aktor,Sensor,Sensor,Aktor,Disadvantages of conventional communication: little content of information just unidirectional data transmission possible strong loading of the c

3、ontrol station by signal conversion (analog to digital) losses of exactness by conversion high expenditure of cabling extension and maintenance are problematical high costs in case of servicing,Introduction of bus systems in the automation,A general diagram of a field bus system,Contol unit,Aktor,Se

4、nsor,Sensor,Aktor,Advantages of bus systems: relief of control unit (by preprocessing of signals within the field devices little cabling (by bus structure) easy starting and servicing cost-cutting up to 40 %,The rest of advantages standardized systems: makes the user independent of special suppliers

5、 large scale of different products cost-effective field devices,The CIM concept,Enterprise level,Production level,Processing level,Plant level,Field level sensors aktors drives,Cell bus,PLC,IPC,CNC,VMEbus,Profibus-FMS Bitbus,Field bus,Profibus-DP Profibus-PA InterBus SERCOS CAN AS-Interface InterBus

6、-Loop,drives,I-Modul,O-Modul,I/O-station,Small control unit,I-Modul,O-Modul,The CIM concept,CIM = Computer Integrated Management many bus participants with low content of information and short response time characterizes the field level the number of bus participants decrease with each level, in ret

7、urn for it increase the content of information and the response time of bus participants special solutions are inconsistent with the demand for a universal field bus system,Topology,Line,Tree,Ring (activ),Ring (physical),PROFIBUS variants,There are three variants of PROFIBUS : Profibus-DP (DP = Dece

8、ntralized Periphery) Profibus-FMS (FMS = Fieldbus Message Spec.) Profibus-PA (PA = Process Automation),Profibus-DP: for connection decentralized I/O-Units with bus cycle times 1ms Optimized for rapid data transmission!,Profibus-FMS: for connecting up of control units with bus cycle times 10 ms,Profi

9、bus-PA: for the operation in environments with danger of explosion,Profibus variants,Probibus FMS,Profibus DP,Profibus PA,Application process,Application process,Application process,DINApplication layer (7) 19245with FMS Part 2 Layers 3 bis 6 are not pronounced Data link layer (2) DIN Physical layer

10、 (1) 19245 Part 1,Transmission medium,DINDP profile 19245DP basic functions Part 3 layers 3 bis 7 are not pronounced Data link layer (2) Subset DIN Physical layer (1) 19245 Part 1,PA profile DP basic functions Layers 3 bis 7 are not pronounced Data link layer (2) DIN 19245 Physical layer (1) Part 4,

11、System coupler,Topology 1,Master,Slave,Slave,Slave,Slave,Each segment allows a maximum number of 32 participants Each end of bus line needs a bus termination (usually in the connector) in order to avoid signal reflexions Segments are able to extend by the use of repeater. So it is possible to connec

12、t further 32 participants, besides greater distances can be spanned.,Topology 2,Master,Slave,Slave,Slave,Slave,Repeater,Transmission rate and the corresponding length of a segment,0,0096,1200,0,0192,1200,0,0937,1200,0,1875,1000,0,5,400,1,5,200,3,0,100,6,0,100,12,100,Mbd,m,Profibus uses a hybrid bus

13、access authority processes: Master-Slave Token Passing,Bus access authority processes1,Master,Slave,Slave,Slave,Slave,Master Slave principle,Master-Slave,The master controls the data exchange over the bus Slaves only answered at requests of the master physical connection of several points, logical c

14、onnection of two points the slaves have to be addressed,Bus access authority processes2,Master,Master,Master,Slave,Slave,Slave,Slave,Token ring,Token passing principle,Token passing,Multimaster system, the token will be reached cyclical from master to master,Stucture of communication,Note: Telegram

15、of Data Exchange (no SAPs),For the data exchange telegrams are used which contains the source address and the destination address Besides the telegram header contains the FCS (frame check sequence) By the FCS a data securing mechanism will realized. A telegram consists of several characters, each ch

16、aracter consists of 11 bits (1 startbit, 8 data bits, 1 parity bit even and 1 stop bit).,DSAP:Destination Service Access Point SSAP:Source Service Access Point,Through the DSAP the destination station are able to distinguish which service has to execute. Example for sercices: demand of diagnosis par

17、ametrization configuration etc.,During the initialization the master has to observe the following chronological order: 1. Demand of diagnosis 2. Change of station address (optional) 3. Parametrization 4. Configuration 5. Repeated demand of diagnosis 6. Data Exchange (of user data),PROFIBUS-DP device

18、 types,DP-Master Kl. 1 (DPM1),DP-Slave,DP-Slave,DP-Slave,DP-Slave,DP-Master Kl. 2 (DPM2),Repeater,Bus cycle time,2,4,6,8,10 (160 E/As),20 (320 E/As),30 (640 E/As),Number of Slaves,Bus cycle time /ms,(Each slave has 2 bytes of input data and output data),10,12,14,12Mbit/s,1,5Mbit/s,500kbit/s,Bus system overview,ASICANInterBusProfibus-DPSERCOS System typeMaster-SlaveMulitmasterMaster-slaveMultimasterMaster-slave Device-orientedmessage-orientedI/O-orientedDevice-orientedDevice-oriented TopologyLine, treeLine