FIELDBUS 1 FIELDBUS 2 FIELDBUS 3 FIELDBUS SCADA

FIELDBUS 1

FIELDBUS 2

FIELDBUS 3

FIELDBUS SCADA process with TCP/IP network and hardwired I/O Operator Administation Internet gateway ADSL 4

FIELDBUS SCADA process with TCP/IP network and PROFIBUS Operator SCADA Administration Internet gateway ADSL 5

FIELDBUS Hvorfor FELTBUS? Ulemper -mere komplekst fejlfinding måling mm. -påvirkelig over for støj -specielt udstyr Fordele -Mere information -Mange signaler i samme kabel -Mindre kabel -Standardiseret udveksling af data (Ligegyldigt om det er SIMENS, ABB eller andre) 6

FIELDBUS The Foundation of PROFIBUS 7

FIELDBUS The ”Process Field Bus” project The specifications of the PROFIBUS standard was a reserch project(1987 -1990) and started with the following 12 members • ABB AEG • Bosch Honeywell • Kloeckner-Moeller Landis & Gyr • Phoenix Contact Rheinmetall • RMP Sauter-Cumulus • Schleicher Siemens Five German Research institues also participated • FZI Karlsruhe IITB • LPR • WZL 8

FIELDBUS PROFIBUS standardisering • • Standardization in Germany (DIN) • European standardization (EN) • International standardization (IEC) New national standards (Ratification as Chinese standard) 9

FIELDBUS PROFIBUS Principles 10

FIELDBUS PROFIBUS is a client/server network To create hierarchy in the network, PROFIBUS defines 2 types of station: active (masters) and passive (slaves) stations. 0 1 0 responses commands 0 1 0 network At least 1 master is mandatory. PROFIBUS networks allow multiple masters. In total 127 stations can be addressed (masters + slaves). 11

FIELDBUS Topology PROFIBUS communicates over a two wire bus structure. Listen Taking over and answering Sending listen 113 1 27 8 listen 52 listen Devices are addressed through a network address (0… 126). Devices are coupled in parallel to the bus. Devices have no fixed position on the bus. Devices can be removed an inserted during operation. 12

FIELDBUS Assigning the address by dipswitches Significance 1 2 4 8 16 32 64 Software Hardware 1 2 3 4 5 6 7 Address = 1+2+0+0+16+0 -0=19 After changing the hardware address, most of the time the device has to be powered down/up. If software assigning is used, be careful when replacing slave hardware, or downloading new software to the slave. 13

FIELDBUS PROFIBUS address map 0 Service-, diagnosis- and programming tool 1. . 2 Masters (class 2) 3. . 125 Slaves (total 123 og 124) 126 Address for: ”Set Slave Address” 127 Broadcast address Most configuration tools block address 0 and 126 for slaves. Address 126 is a default address for slaves with software address settings. Address 127 is a broadcast address (only visible with a busmonitor). Maximum 124 DP slaves per bus!!! 14

FIELDBUS Communication relations To one Multicast Because of the bus structure, no responses are generated when the ’multicast’ and ’broadcast’ messages are used (collision) Broadcast 15

FIELDBUS Medium access by token passing 16

FIELDBUS Transmission speed (baudrate) PROFIBUS offers the user the possibility to choose from 10 transmission speeds (RS 485): 9. 6 19. 2 45. 45 93. 75 187. 5 500 1500 3000 6000 12000 Kbit/s Remarks: • The transmission speed determines the maximum cable length and vice versa. • The transmission speed has to be set identically at all the masters on the same bus. • Most slaves detect the baudrate automatically. • Because of economic and techinical reasons some produts do not support all transmission speeds. • Some older products do not support 45. 45 kbit/s. 17

FIELDBUS PROFIBUS CABLING 18

FIELDBUS Cable construction and wire colors RS 485 • Baud rates from 9. 6 Kbit/s to 12 Mbit/s • Shielded twisted pair cable • 32 devices per segment • Distance: 12 Mbit/s = 100 m; 1. 5 Mbit/s =200 m; Kbit/s = 1000 m • Distance extendable with repeaters MBP-IS • Fixed baud rate of 31. 25 Kbit/s • Intrinsic safety (option and power over the bus) • Shielded twisted pair cable • Distance up to 1900 m per segment depended on Ex-class and power consumption • 10 -32 devices per segment, dep. On Ex-class and power consumption Fiber optics • Baud rates from 9. 6 Kbit/s up to 12 Mbit/s • Mono mode, Multimode, plastic or PCS/HCS fibers are available • Distance extendable With repeaters up to 100 km 19

FIELDBUS Design specification What are the critical points when designing RS 485 networks Operator Administration SCADA Cable length Shielding & Grounding Internet gateway Stub lines Termination Number of devices 20

FIELDBUS PROFIBUS Cable The A and B line are green and red: A-line TXD-N 1 - Green B-line TXD-P 2 + red 4. Foil for frequencies above 50 MHz 1. A-line (green) and B-line(red) 2. ”Tubes for a round cable 3. Braid for frequencies up to 50 MHz. 21

FIELDBUS Cable types All kinds of cables are available for areas in which the standard PROFIBUS cable cannot be used. • • • Robust Cable Food Cable Underground Cable Trailing Cable Festoon Cable FRNC Cable Flexible Cable Shipboard Cable Hybrid Cables 22

FIELDBUS Cable colors Standard cable Ground-/shipboard cable Robust purple black green PROFIBUS PA cable blue yellow AS-I Industrial Ethernet yellow green black orange 23

FIELDBUS DB 9 connector - Structure For devices with a DB 9 connector, standardized plugs are available for chaining the bus. The connector technology is NOT defined in the PROFIBUS standard. The PROFIBUS standard describes some recommended implementations DB 9 and M 12. Versions are available on which an extra female connector is implemented. It is recommended to put one on every segment for maintenance purposes. 24

FIELDBUS DB 9 connector – Connection method The method of connecting the cable is very important. When termination is enabled, the second channel is disconnected. Ton Toff AB AB Shield AB AB Cable Insulation 25

FIELDBUS Cable length versus Baudrate (Kbit/s) Segment length (m) 9. 6 19. 2 45. 45 93. 75 187. 5 500 1500 3000 6000 1200 1200 1000 400 200 100 100 Baudrate transitions in which the cable length reduces with more than 50% These length are defined for 1 segment with 32 bus loads! 26

FIELDBUS Termination and PROFIBUS DP 27

FIELDBUS Termination - Structure The bus is terminated on both ends with terminating resistors +5 V 390 Ohm B 3, 05 V 220 Ohm A 1, 95 V 390 Ohm • The termination consists of 3 resistors. • The power supply provides a valid logic level when non of the devices are active on the bus • Without the power supply the terminating resistor is not equal to the cable impedance. GND 28

FIELDBUS Exercise 29

FIELDBUS Termination – Active variant Master Power Active Termination ”last” Slave Slave In this segment every station can be removed or powered down without disrupting the network 30

FIELDBUS Repeaters - Introduction Using Repeaters is a solution to increase the cable length and the number of stations (more than 32). Max 1200 m T Max 31 stations T T Max 29 stations T T Max 1200 m Max 31 stations T Max 1200 m T Repeaters are also bus loads and terminating resistors need to be placed again 31

FIELDBUS Repeaters - Structue Usin Repeaters is a solution to increase the cable length and the number of stations (more than 32). Segment 1 3. Termination can be activated when the bus ends/starts the at the repeater. Segment 1 Isolation 1. The shielding can still be 1 on 1. Segment 2 Repeaters are also bus loads and terminating resistors need to be placed again 32

FIELDBUS DP/DP Coupler - Structure DP Master (Bus Adress #1) DP slave (Bus Address #3) DP slave (Bus Address #4) DP slave (Bus Address #5) DP 1 DP slave (Bus Address #7) DP 2 DP network #1 DP slave (Bus Address #3) DP Master (Bus Adress #1) DP slave (Bus Address #4) DP slave (Bus Address #5) DP network #2 33

FIELDBUS Exercise Termination 34

FIELDBUS PROFIBUS AND GSD FILES 35

FIELDBUS GSD (Generic Station Description) “The slave description for configuration tools” -File name is 8 characters – extension • Maximum 4 characters identify the manufacturer, product, etc. (SIEM, EH_) • 4 characters the Ident__Number (806 A , 1501) • Total: EH__1501, SIEM 806 A -File extension defines the language • “GSD” is standard (must be in English if this is the only GSD) -For support of more languages: • English =“. gse” • French = “. gsf” • German = “. gsg” • Italian = “. gsi” • Portuguese = “. gsp” • Spanish = “. gss” 36

FIELDBUS GSD Example 37

FIELDBUS PROFIBUS AND RS-485 38

FIELDBUS RS 485 and PROFIBUS Device R TTL/ CMOS Device T Z R TTL/ CMOS T Z 3. Because of the parallel resistors, a maximum of 32 devices is allowed on a segment Device R TTL/ CMOS 5. Termination on the end of the cable T Z +5 V Maximum 32 devices. 390 E B 220 E +/- U 220 E A 390 E GND 1. Sending data by means of current and polarity change. 390 E 4. The differential voltage should be +/ -200 m. V or more. In reality in the range 4 to 5 V. 2. The receivers read the current flow by input impedance (Z) 6. Pull-up/down resistors are essential for the basic current. GND 39

FIELDBUS RS 485 signal levels Line A Ca. 2. 5 V Zero axis 1 Line B Ca. 2. 5 V 2 Zero axis Differential Ca. 2. 5 V Voltage A-B Zero axis Ca. 2. 5 V 1=Start of data transmission 2=Idle phase, no data transmission, level determined by bus termination 40

FIELDBUS 41

FIELDBUS Testing If you have bus problems, it is recommended to set the baudrate at the lowest possible value (9. 6 Kbit/s. ) Most networks operate ‘correctly’ on this speed even when they have installation, cabling and termination faults Low Baudrate Low % of Overall Bit Transmission Time High Baudrate High % of Overall Bit Transmission Time At higher baudrates there is more chance of bus faults 42

FIELDBUS Grounding and shielding 43

FIELDBUS 44

FIELDBUS Termination - Structure • Ground as many points as possible. This reduces the resistance (less noise) • Be careful of the amount of current flowing trough the shield. When the current gets too high, use an extra ground cable, fiber optic or repeaters with isolation • Avoid the use of ‘pigtails’ • Avoid connection with the ‘minus’ of power supplies. Don’t ground on 1 side! 45

FIELDBUS Grounding and shielding between cabinets Master Slave Ground rail PROFIBUS cable Ground cable 46

FIELDBUS Air gaps (1) The voltage levels and applications of cable needs to be classified into categories. Category I: Fieldbus and LAN cables (PROFIBUS, ASI, Ethernet, etc. ). Shielded cables for digital data (printer, RS 232 etc. ). Shielded cables for analog and digtal signals (≤ 25 V). Low voltage cables (≤ 60 V). Coax cables. Category II: Cable with DC voltage >60 V and ≤ 400 V. Cable with AC voltage >25 V and ≤ 400 V. Category III: Cable with DC and AC voltage >400 V. Telephone cables Category IV: All cables from group I to III the direct danger of lighting strikes (connections between buildings or open air applications) 47

FIELDBUS Air gaps (2) When cables are placed side by side, they have to comply to the following air gaps: ≥ 20 cm Cable category I ≥ 10 cm ≥ 50 cm Cable category II Cable category IV ≥ 10 cm Cable category III ≥ 50 cm The air gaps are based on air space. In case of grounded metal plates, the distances can be reduced. Cables of different categories might cross each other 48

FIELDBUS Air gaps (3) A measurement of a packing machine in which the PROFIBUS cables are placed too close to power lines. Cables of different categories my cross each other 49

FIELDBUS Fault top-5 1. Termination. 2. Power lines. 3. Cabling rules. 4. Configuration fault. 5. Damages or not-certified interfaces. 50

FIELDBUS PROFIBUS messages From Analyze- Equipment 51

FIELDBUS DP slave state machine Power on/ Reset Diagnostics • The master constantly polls the diagnostics of every slave Which is not available Parameters • When the slave gives a reaction to a diagnostic request the parameters are transmitted Configuration • After the parameters, the configuration is transmitted Diagnostics • After configuration, the master requests diagnostics to check if everything has been accepted Data exchange • When the slave has accepted all the information, the master will constantly exchange data with the device. 52

FIELDBUS DP slave state machine (2) 1. Diagnostics 2. Parameters 3. Configuration 4. Diagnostics 5. Data exchange 53