Siemens SIMATIC ET 200AL System Manual page 1228

Table of contents
Preface ................................................................................................................................................... 3
1 Documentation guide .............................................................................................................................. 7
2 Description ............................................................................................................................................ 10
2.1 Introduction to PROFIBUS ...................................................................................................... 10
2.1.1 Applications of PROFIBUS DP ............................................................................................... 11
2.1.2 PROFIBUS terminology .......................................................................................................... 12
2.1.3 PROFIBUS DP interface ......................................................................................................... 16
2.2 Structure of PROFIBUS networks .......................................................................................... 17
2.2.1 Passive network components for RS 485 networks ............................................................... 19
2.2.1.1 RS 485 cables ......................................................................................................................... 19
2.2.1.2 PROFIBUS FastConnect system ............................................................................................ 20
2.2.1.3 PROFIBUS bus connector ...................................................................................................... 22
2.2.1.4 M12 bus connector ................................................................................................................. 24
2.2.1.5 Bus terminals for RS 485 networks ........................................................................................ 24
2.2.1.6 M12 bus terminating resistor .................................................................................................. 24
2.2.2 Passive components for optical networks............................................................................... 25
2.2.2.1 Fiber-optic cables .................................................................................................................... 25
2.2.2.2 Plastic and PCF fiber-optic cables .......................................................................................... 26
2.2.2.3 Glass fiber-optic cables........................................................................................................... 27
2.2.3 Active network components .................................................................................................... 29
2.2.3.1 Network components in electrical networks............................................................................ 29
2.2.3.2 Network components in optical networks ............................................................................... 33
2.2.4 Examples for topology ............................................................................................................ 35
2.2.4.1 Topology with RS485 repeater ............................................................................................... 35
2.2.4.2 Topology with diagnostic repeater .......................................................................................... 37
2.2.4.3 OLM topology .......................................................................................................................... 40
2.2.4.4 WLAN topology ....................................................................................................................... 40
2.2.4.5 Connecting PROFIBUS to PROFINET ................................................................................... 41
3 Parameter assignment/addressing ........................................................................................................ 42
3.1 Assigning the DP slave to a DP master .................................................................................. 43
3.2 PROFIBUS address ................................................................................................................ 45
3.3 Network settings ..................................................................................................................... 46
3.4 Cable configuration ................................................................................................................. 49
3.5 Additional network stations ..................................................................................................... 51
3.6 Bus parameters ....................................................................................................................... 52
3.7 Constant bus cycle time .......................................................................................................... 55
PROFIBUS with STEP 7 V13
Function Manual, 12/2014, A5E03775446-AC
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