INDUSTRIAL NETWORK PROFIBUS

Department of Control and Automation

INDUSTRIAL NETWORK

PROFIBUS
th
Nov 13 , 2015


CONTENTS
 INTRODUCTION
 OSI MODELS
 PHYSICAL LAYER
 EXAMPLE
 ADVANTAGE, DISADVANTAGE
 APPLICATION


INTRODUCTION

PROFIBUS (Process

Field

Bus)

was

first

promoted

BMBF (German department of education and research) 

in

1989

by


INTRODUCTION
PROFIBUS is a widely accepted international networking standard
IEC 61158 in 2000


INTRODUCTION
PROFIBUS consists of 3 Communication Profiles:
 FMS (Fieldbus Message Specification),  DP (Distributed Peripheral),  PA (Process
Automation)


OSI MODELS


PHYSICAL LAYER
 With electrical transmission RS485, Bit rates from 9.6 kbit/s to 12
Mbit/s . The cable length is limited from 100 to 1200m, primarily used
with PROFIBUS DP.
 With optical transmission via fiber optics, star-, bus- and ringtopologies are used. The distance can be up to 15 km.

PHYSICAL LAYER
•

Maximum number of devices:

DP : 126 stations/bus ( 244 bytes data limited in/out for one slave)

•

Communication Method:

DP : peer to peer, multicast or master-slave( token pasing)


PHYSICAL LAYER


DATA LAYER
 The data layer FDL (Field bus Data Link) can be differentiated by their
start delimiter (SD):
 No data: SD1 = 0x10
 Variable length data: SD2 = 0x68
 Fixed length data: SD3 = 0xA2
 Token: SD4 = 0xDC
 Brief acknowledgement: SC = 0xE5


DATA LAYER

SD: Start Delimiter
LE: Length of protocol data unit
Ler: Repetition of protocol data unit
FC: Function Code
DA: Destination Address
SA: Source Address
DSAP: Destination Service Access Point
SSAP: Source Service Access Point
PDU: Protocol Data Unit (protocol data)
FCS: Frame Checking Sequence
ED: End Delimiter (= 0x16 !)


DATA LAYER


APPLICATION LAYER

 FIELDBUS MESSAGE SPECIFICATION (FMS)
The FMS Communication Profile is designed for communication at cell
level. At this level, programmable controllers (PLCs and PCs)
communicate primarily with each other.
In this application area a high degree of functionality is more important
than fast system reaction times.


APPLCATION LAYER
 PROFIBUS DP:
The functions of the PRO-FIBUS DP communication protocol are
distributed over three performance levels :

* DP-V0 for cyclic exchange of data and diagnosis
* DP-V1 for acyclic data exchange and alarm handling
* DP-V2 for isochronous mode and data exchange broadcast (slaveto-slave communication)


EXAMPLE


ADVANTAGE
 Used extensively with 1,100 member companies worldwide.
 Network support at the level of equipment, process control, and
Ethernet.
 Available interfaces for variable speed drive applications and motor
control center (Profibus DP).
 The gateway allows integration Profibus PA directly with Profibus DP
network.
 Host interface are available for most PLC, DCS and computer systems.


DISADVANTAGE
 Profibus DP does not have Intrinsically Safe application support.
 The requirements for wiring, power, grounding, bonding and terminal
must be taken into account during the design and installation.

 Do not use in explosive and noise environments.


PROFIBUS-DP PROFIBUS-PA
 Transmission rate: 9.6 Kbit/s –
12Mbit/s

 Respond time: 1-5ms
 Requires separate power.
 Use RS-485 to exchange data.
 Not intrinsically safe.

 Transmission rate: 31.25 Kbit/s
 Respond time: <60ms
 Provides power over the same
two wires.
 Use MBP (Manchester coded,
bus powered) protocol.
 Intrinsically safe.


APPLICATION
 Production System of CocaCola at HM Interdrink
(Germany) use PROFIBUS-DP to increase speed of the
data circulation process and PROFIBUS-FMS to circulate
asynchronous data with a large amount of data.

 Ice cream production System Tai Chang Wall (China).
PROFIBUS-DP is used to connect field devices to the
central control system. Through PROFIBUS-DP, the
central controller can control and directly oversee
entire valve which are used to mix all material.


- The end THANK FOR
YOUR LISTENING

References:
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