The document discusses Foundation Fieldbus, an open standard for process automation communication. It was established by the International Society of Automation to create a single international fieldbus standard. Foundation Fieldbus uses digital, serial communication between intelligent field devices. It provides wiring and installation savings, enhanced data availability, improved user interfaces, and interoperability between devices.

1. FOUNDATION
FIELDBUS
JUSTIN BABY

2. Contents
 Introduction
 Foundation Members
 What is Fieldbus?
 FF Components
 FF Segment Topology
 Comparison
 Benefits
 Applications

3. Introduction
 Established by International Society of
Automation
 Goal: A single international, interoperable
fieldbus standard.
 Not-for-profit corporation
 Fieldbus technology is based on the work of the
IEC and ISA. IEC std. for FF – IEC 61158
 Fieldbus Foundation has nearly 100 member
companies, which supply over 90% of the
worlds instrumentation and control products.

4. Foundation Members

5. What is Fieldbus?
 Fieldbus is a digital, serial two-way, multi-drop
communication link among intelligent field
devices and automation systems.
 It is an open architecture, developed and
administered by the Fieldbus Foundation.
 H1 (31.25kbps)
 HSE (High Speed Ethernet)

6.  <1930’s – Direct connected devices
 1940’s – Pneumatic signal transmission
 1950’s – 10-50/4-20mA replacing 3-15psi
 1970’s – Process computers appear (PLCs)
 1980’s – DCS implemented
 1990’s – First FF systems
 2000’s – Fieldbus crosses “chasm”

7. FF Components

9. Fieldbus cable Types

10. FF Segment Topology
 Point-to-point
 Chicken-foot (Tree) Topology
 Daisy chain
 Spur Topology
Trunk
Spur

11. Comparison

12. Benefits

13. 1. Wiring/Installation Savings

14. 2. Control Anywhere

15. 3. More Available Data

16. 4. Enhanced User Interface

17. 5. Interoperability

18. Fieldbus Communication

19. One of the most important aspects of
FOUNDATION fieldbus is its ability to collect and
deliver vast amounts of information - not only
process variables and control signals, but other
types of instrument and process data as well.

20. Physical Layer
 Translating messages into physical signals
on the wire - and vice versa
 The physical layer also provides the
common electrical interface for all
FOUNDATION fieldbus devices.
 The FOUNDATION fieldbus physical layer is
defined by approved standards (IEC
61158-2 and ANSI/ISA 50.02, part 2).

21. Data Link & Application Layers
 It combines several technologies that together
control transmission of data on the fieldbus.
 The data link and applications layers provide
a standard way of "packaging" the data, as
well as managing the schedule for
communication and function-block
execution.
 They enable process control while providing
standardization and interoperability.

22. User Layer
 It enables user to interact with the other layers
and with other applications.
 The user layer contains
Resource blocks - describes characteristics of the
fieldbus device such as device name, mfr. and
serial number, etc.
Transducer blocks - used to configure devices
Function blocks - The Control System Strategy is built
using Function Blocks. Input and output parameters
of Function Blocks can be linked over the fieldbus.
 Device descriptions enable the host system to
interact with and understand these blocks without
custom programming.

23. Important Definitions

24. Scheduled Communications
 All devices and function blocks on a
FOUNDATION fieldbus segment execute and
communicate process control information on
a regular, repeating cycle.
 Timing for this type of communication is
determined by a master schedule in a Link
Active Scheduler, which is a function residing
in the host system or one of the devices on
the segment.

25. Application Clock
 Every device on a FOUNDATION fieldbus
segment shares the same time.
 A system management function called the
application clock periodically broadcasts the
time - either local time or Universal
Coordinated Time -- to all devices. Each
device uses an internal clock to keep time
between these synchronization broadcasts.

26. Link Active Scheduler
 The link active scheduler (LAS) function
maintains the central, deterministic
schedule for communication between
devices on a segment.
 It improves overall communication
reliability by compelling each device to
transmit cyclic data when it's scheduled
to do so.

27. Device Address Assignment
 FOUNDATION fieldbus carries signals to and from
several devices over the same cable. To identify
which information is associated with which
device, each device is assigned an address.
 Depending on the communication protocol,
addresses can be assigned in several ways, from
dip switches or off-line addressing to automatic
online assignment.
 Online addressing helps avoid problems such as
duplicate devices with the same address, but by
itself does not guarantee there are no addressing
errors.

28. Signals
 Devices on a Fieldbus segment transmit digital
signals to each other over the same wires that
power the devices.
 A DC bus voltage (nominally 24V but can be
from 9‐32VDC) is supplied to the devices on the
segment by the Fieldbus Power Supply. A
Fieldbus device draws a constant amount of
current when not transmitting. To transmit
information, the device varies the amount of
current it draws from the segment to create a
signal “riding” on the 24VDC.
 Digital data is sent on the Fieldbus at a rate of
31.25 Kbits/second.

29. Fieldbus Signal

30. Fieldbus Power Supply
 Isolator – To improve noise immunity
 Power Conditioner – Like a one way valve
 Current Limiter – Prevent damage from
short-circuit or over-load conditions

31. Applications
 Refining
 Petrochemicals
 Power generation
 Food & beverage
 Pharmaceuticals
 Nuclear Applications

32. Zone-1 (Intrinsically Safe)

33. Zone-2 (Non - Incendive)

34. References
 Fieldbus Installation in a DeltaV™ Digital
Automation System – Emerson Process
Management
 QGX/20/00/IN/TS/NA/040, Rev-E2 –
Foundation Fieldbus Design Specification
 www.wikipedia.com/foundation_fielbus