Compliments of:
The Fieldbus Foundation© 2004-2012 Fieldbus Foundation

	
  

	
  

FOUNDATION™ Fieldbus
System Engineering Guidelines
	
  
	
  

	
  

	
  

(AG-181) Revision 3.2.1
This preface, as well as all footnotes and annexes, is included for informational purposes andis not part of AG-181.
This document has been prepared under the direction of the End User Advisory Council(EUAC) of the Fieldbus Foundation. To be of real value, it should not be static but subject toperiodic review. Toward this end, the foundation welcomes all comments and criticisms, andasks that they be addressed to:

	
  

	
  

	
  

	
  

Fieldbus Foundation
9005 Mountain Ridge Drive
Bowie Building - Suite 200
Austin, Texas 78759-5316 USA
Tel: 512.794.8890
Fax 512.794.8893
E-mail: marketing@fieldbus.org
Visit our Worldwide Web Site:www.fieldbus.org
This document in its present revision, and at time of publication, recognizes that High Speed
Ethernet (HSE) products are available from the Fieldbus Foundation and its members.
Although HSE implementation is currently not widespread, guidelines for installation and use
are provided. The protocol for FOUNDATION™ Fieldbus for Safety Instrumented Functions (FFSIF) has been approved by TÜV and its implementation has been successfully demonstrated.
Commercial products for installations are not yet available, but practical pilot installations arebeing commissioned and planned. Preliminary guidelines for design and implementation are
included in this revision. A future revision of this document will incorporate further guidelines
for the design, installation and implementation of FOUNDATION Fieldbus for Safety
Instrumented Functions.
The use of specific vendors/manufacturers in this document does not entail implicit
endorsement of the product over other similar products by the authors or the Fieldbus
Foundation. Individuals using this document are encouraged to seek out equivalent function
equipment from other sources of which the authors may be unaware. To assist in our efforts tomake this document as relevant as possible, should such equipment be known to a user of thisdocument, please forward that information to the address given above.
It is the policy of Fieldbus Foundation to encourage and welcome the participation of allconcerned individuals and interests in the development of FOUNDATION fieldbus standards,
recommended practices, and technical reports. Participation in the Fieldbus Foundation
standards-making process by an individual in no way constitutes endorsement by the employerof that individual, of the Fieldbus Foundation, or of any of the standards, recommended	
   Revision 3.2.1- ii -

September 2012

	
  

	
  

	
  

practices, and technical reports that the Fieldbus Foundation develops.
The Fieldbus Foundation would like to thank the End User Advisory Council and the membersof the End User Councils who have committed so much time and effort to the preparation ofthis guide.
David Lancaster (Editor)
Dave Brown
Chuck Carter
Bindert Douma
Clark Cogswell
Glenn Dehler
Patrick Flanders
Audun Gjerde
Rong Gul
William Hamilton
Yoshitsugu Morioka
Larry O’Brien (Editor)
John Rezabek
Herman Storey

Trine University
EUC, USA
Bechtel OG&C
EUC, USA
Lee College
EUC, USA
STC-Brielle
EUC, EMEA
Shell Global Solutions
EUC, USA
Shell Global Solutions
EUC, USA
Saudi Aramco
EUC, Saudi Arabia
Shell Global Solutions
EUC, EMEA
Shell Global Solutions
EUC, EMEA
Shell Global Solutions
EUC, USA
Waseda University
EUC, Japan
Fieldbus Foundation
Fieldbus Foundation, USA
Ashland
EUAC Chairman
Herman Storey
EUAC, USA
Consulting, LLC
The Fieldbus Foundation wishes to acknowledge the following individuals for their dedication in
the creation of the original version of this document. Without their dedication, this guide would
not have been possible:
Ian Verhappen (Editor)
Chris Baltus
John Bazley
Ambrose Hargan
Henry Marks
Norihko EGI
Nola Ogar
Deon RaeJim Russell
Herman Storey
Ron Szanyi
Al ChanJim Sprague
Ralph A. Hartman II	
   Revision 3.2.1

SAIT
DSM
Beca Simons
CSBP
Marks & Associates
IT Engineering (Retired)
BP Group
Chevron Texaco
Keyfleet Pty. Ltd.
Shell Global Solutions
ExxonMobil
Canadian Natural
Resources Ltd.
Saudi Aramco- ii -

Chairman, EUAC, Canada
EUAC, Europe
EUC, Australia
EUC, Australia
EUC, USA
EUC, Japan
EUC, USA
EUC, USA
EUAC, Australia
EUAC, USA
Director, Fieldbus Foundation
EUC, Canada
EUC, Saudi Arabia

September 2012

	
  

	
  
	
  

	
  

	
  

Rev. No.
0
1.0
2.0
3.0
3.1
3.2
3.2
3.2
3.2
3.2
3.2
3.2
3.2
3.2
3.2
3.2.1
3.2.1
3.2.1
3.2.1
3.2.1
3.2.1
3.2.1
3.2.1

Revision 3.2.1

Date
October 2003
December 2003
August 2004
January 2009
March 2010
January 2012
May 2012
May 2012
May 2012
May 2012
May 2012
May 2012
May 2012
May 2012
May 2012
September 2012
September 2012
September 2012
September 2012
September 2012
September 2012
September 2012
September 2012

Description
Original Release
Editorial Revisions
Editorial Revisions
Incorporate Current Methodologies
Incorporate Editorial Comments and Revisions
Incorporate Editorial Comments and Revisions
Rework Sections on FISCO
Revised Sections on Design Rules
Revised Sections on Cable Length
Revised Sections on Surge Protection
Reformatted Document
Removed Appendix on Grounding andShieldingDrawings
Revised Topology
Added Discussion on Existing Wiring
Revised Section on Segment SchedulingReplaced Figure 7-6
Replaced Figure 7-7
Replaced Figure 7-8
Replaced Figure 7-9
Deleted Reference to IEC 60079-13 Standard
Revised Figure 7-2
Revised Figure 7-3
Revised Figure 7-4

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By
IV
IV
IV
DSL
DSL
LOB
LOB
LOB
LOB
LOB
LOB
LOB
LOB
LOB
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LOB
LOB
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September 2012

	
  

	
  

	
  
	
  
	
  

	
  

	
  

	
  

	
  

Revision Memo
REVISION 1.0 – DECEMBER 2003
Addition of Saudi Aramco contributors to preface
Renumber 1.3.3 to 1.3.2
Renumber 4.4.3 to 4.4.2
Reference in Section 8.6.2 changed from 6.5.2 to 6.7.2
REVISION 2.0 – AUGUST 2004
Add abbreviation MOV – Motor Operated Valve to abbreviations list.
Section 2.2.9 Addition of reference to AG-163
Section 2.3.5 Correct IAONA URL from http://www.iaona-eu-com to www.iaona.org
Section 5.2.7 Statement of power conditioner isolation
Section 6.3.5 Change to 8/20uS, not 8/20S
Section 6.5 & 6.6 Rewritten
Section 6.7 Addition of Section on FNICO. Renumber balance of Section 6
Section 7.3.3 Correction SM Timer default settings were 2440000 (76.25 seconds) changed to 1440000(45 seconds)
Table title changes “Network/Segment Checkout Form” and “Fieldbus Cable Checkout Form”
Update noise levels to <75 mV and lowest signal level to 150 mV in “Network/Segment Checkout Form”
REVISION 3.0 – JANUARY 2010
General revision
Combined Sections 1, 2 and 3
Combined items from other documents
Restructure sections to emulate a project development
Added Project Requirements Section
Added FOUNDATION Fieldbus for Safety Instrumented Functions
Revised Host System Requirements
Revised Software Configuration Guidelines
Revised Field Device Requirements
Revised Ancillary Device Requirements
Revised Fieldbus Network/Segment Design Guidelines
Revised Factory Acceptance Test Procedures
Revised Site Installation Guidelines
Revised Documentation Requirements
Added Appendices
REVISION 3.1 – March 2010
Incorporated comments
Changed order of Sections 8 and 9
Added and revised order of Appendices

	
  
	
  
REVISION 3.2 – May 2012
Incorporate Editorial Comments and Revisions
Rework Sections on FISCO	
  Revision 3.2.1-4-

September 2012	
  Revised Sections on Design Rules
Revised Sections on Cable Length
Revised Sections on Surge Protection
Reformatted Document
Removed Appendix on Grounding and Shielding
Revised Topology Drawings
Added Section on Use of Existing Wiring
Clarified that VCRs are Typically not Used on Newer Systems
Revised Section on Segment Scheduling
Cleaned up References to ISA Standards
Revised Grounding Graphics
REVISION 3.2.1 – September 2012
Further Formatting Changes
Replace Grounding Figures
Remove Outdated Standards References
Updated Figures on Segment Current Draw and Voltage	
  Revision 3.2.1-5-

September 2012

	
  

	
  

	
  

	
  
	
  

	
  

CautionThe use of this guide may involve hazardous materials, operations or equipment. The guidecannot anticipate all possible applications or address all possible safety issues associated withuse in hazardous conditions. The user of this guide must exercise sound professional
judgment concerning its use and applicability under the user’s particular circumstances andaccording to their established corporate policies and procedures. The user must also consider
the applicability of any governmental regulatory limitations and established safety and healthpractices before implementing this standard.
Disclaimer of Warranties
This document is informative only and is provided on an “as is” basis only. The document may
be subject to future additions, modifications or corrections without notice. The Fieldbus
Foundation disclaims all warranties of any kind, express or implied, including any warranty ofmerchantability or fitness for a particular purpose, for this document. IN NO EVENT WILL THE
FIELDBUS FOUNDATION BE RESPONSIBLE FOR ANY LOSS OR DAMAGE ARISING OUT
OF OR RESULTING FROM ANY DEFECT, ERROR OR OMISSION IN THIS DOCUMENT ORFROM ANYONE’S USE OR RELIANCE ON THIS DOCUMENT.

Revision 3.2.1-6-

September 2012

	
  

	
  

	
  

How To Use This Document

	
  

	
  

	
  

	
  
	
  

This document reflects standard industry practices for the application FOUNDATION fieldbus H1
and High Speed Ethernet (HSE) projects at time of publication. As this is a “living document,” itwill be maintained and updated periodically to reflect changes in the technology including thefurther adoption and application of HSE and the further use of FOUNDATION Fieldbus for Safety
Instrumented Functions.
The authors recognize that each facility planning to or installing a FOUNDATION fieldbus project
may not wish to adhere to all the recommendations as reflected in this guideline. Towards that
end, the End User Advisory Council recommends that rather than change this document,
which has several cross-references, users instead prepare a forward clearly identifying thosesections to be modified or applied in a different way. An example of this follows:“XYZ Company applies Section 7.3.3 to provide additional grounding protection for fielddevices."
Recommended changes, additions or suggestions should be forwarded via e-mail to:euac@fieldbus.org

Revision 3.2.1
	
  

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September 2012	
  Table	  of	
  Contents	
  
	
  
	
  

1.0	
  INTRODUCTION .....................................................................................................................................................16	
  1.1	
  Contents ............................................................................................................................................................16	
  1.2	
  Purpose .............................................................................................................................................................17	
  1.3	
  Scope.................................................................................................................................................................17	
  1.3.1	  General.......................................................................................................................................................18	
  1.3.2	
  Project	  Consideration.................................................................................................................................18	
  1.4	
  References.........................................................................................................................................................18	
  1.4.1	
  FOUNDATION	
  Fieldbus	
  Specifications............................................................................................................18	
  1.4.2	
  Industry	
  Codes	
  and	
  Standards....................................................................................................................18	
  1.4.3	  Other	  References .......................................................................................................................................19	
  1.5	
  Definitions .........................................................................................................................................................19	
  1.5.1	  General	
  Definitions ....................................................................................................................................19	
  1.5.2	
  FOUNDATION	
  Fieldbus	
  Definitions ................................................................................................................20	
  1.6	
  Abbreviations ....................................................................................................................................................33	
  2.0	
  FOUNDATION	
  FIELDBUS	
  PROJECT	
  REQUIREMENTS..................................................................................................36	
  2.1	
  Introduction ......................................................................................................................................................36	
  2.2	
  Use	  of	
  Approved	
  Products ................................................................................................................................36	
  2.3	
  Early	
  in	
  the	
  Project ............................................................................................................................................36	
  2.3.1	
  Project	
  Evaluation ......................................................................................................................................36	
  2.3.2	  Training ......................................................................................................................................................37	
  2.3.3	
  Implementation	
  Basis.................................................................................................................................37	
  2.3.4	
  Host	  Selection ............................................................................................................................................37	
  2.3.5	  Component	  Selection .................................................................................................................................38	
  2.3.6	  Work	  Processes ..........................................................................................................................................38	
  2.3.7	  Division	
  of	
  Responsibility ...........................................................................................................................39	
  2.3.8	  Integration	
  Tools	
  between	  Offices .............................................................................................................39	
  2.3.9	  Integration	
  with	  Suppliers ..........................................................................................................................39	
  2.3.10	
  Device	  Integration	
  Testing .......................................................................................................................39	
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-8-

September 2012

	
  

2.4	
  During	
  Project	  Design........................................................................................................................................39	
  2.4.1	  Training	
  (more,	  detailed)............................................................................................................................39	
  2.4.2	
  Risk	  Assessment	
  Rules	
  and	
  Review ............................................................................................................40	
  2.4.3	
  Segment	
  Loading	
  Rules	
  and	
  Review...........................................................................................................40	
  2.4.4	
  Methods	
  (Templates) .................................................................................................................................40	
  2.5	
  Implementation.................................................................................................................................................40	
  2.5.1	  Training ......................................................................................................................................................40	
  2.5.2	
  Host	  System	  Performance..........................................................................................................................40	
  2.5.3	
  Diagnostics	
  Training ...................................................................................................................................41	
  2.5.4	
  Maintenance	
  Methods...............................................................................................................................41	
  2.5.5	
  Operations	  –	  How	  to	
  Optimize	
  the	
  Use	  of	
  FOUNDATION	
  Fieldbus ...............................................................41	
  2.5.6	
  Review	
  Installation .....................................................................................................................................41	
  2.5.7	
  Review	
  Field	
  Changes.................................................................................................................................41	
  2.6	
  Summary ...........................................................................................................................................................42	
  3.0	
  FOUNDATION	
  FIELDBUS	
  HOST	
  SYSTEM	
  REQUIREMENTS .........................................................................................43	
  3.1	
  Use	  of	
  Standard	
  Products..................................................................................................................................43	
  3.2	
  Spare	
  Capacity	
  and	  Expansion...........................................................................................................................43	
  3.3	
  Redundancy.......................................................................................................................................................44	
  3.4	
  Architecture	
  of	
  Engineering	
  and	
  Maintenance	  Workstations...........................................................................45	
  3.5	
  Interoperability .................................................................................................................................................46	
  3.5.1	
  Host	  Profile	  Registration	
  Process ...............................................................................................................46	
  3.7	
  Additional	
  Capabilities ......................................................................................................................................47	
  3.8	
  Support	
  for	
  FOUNDATION	
  Fieldbus	
  Functionality ................................................................................................47	
  3.8.1	
  Host	  System	  Fieldbus	
  Functionality ...........................................................................................................47	
  3.8.2	
  Data	  Transfer	
  Capabilities ..........................................................................................................................48	
  3.9	
  Configuration	
  Tool.............................................................................................................................................48	
  3.9.1	  Integration..................................................................................................................................................48	
  3.9.2	
  Features......................................................................................................................................................48	
  3.9.3	  Capabilities .................................................................................................................................................49	
  3.9.4	
  Required	
  Function	
  Blocks...........................................................................................................................49	
  3.10	
  Troubleshooting,	
  Maintenance	
  and	
  Diagnostics.............................................................................................50	
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September 2012

	
  

3.11	
  Advanced	
  Diagnostics	
  and	  Computer-­‐based	
  Maintenance ............................................................................51	
  3.11.1	
  Asset	  Management	
  Systems ....................................................................................................................51	
  3.11.2	
  Minimum	
  Diagnostic	
  Requirements.........................................................................................................51	
  4.0	
  SOFTWARE	  CONFIGURATION	  GUIDELINES ...........................................................................................................53	
  4.1	
  Control	
  System	
  Graphics ...................................................................................................................................53	
  4.2	
  FOUNDATION	
  Fieldbus	
  Device	  Segment	
  Addressing ............................................................................................53	
  4.3	
  Control	
  Functionality	
  Location ..........................................................................................................................54	
  4.3.1	  Recommendations	
  for	  Display	
  and	
  Alarm	
  of	
  Loop	  Variables	
  for	
  Control	
  in	
  the	
  Field:...............................55	
  4.4	
  Segment	  Scheduling ..........................................................................................................................................55	
  4.5	
  Configuration	  Options	  and	
  Defaults..................................................................................................................56	
  4.5.1	
  Control	
  Narrative........................................................................................................................................56	
  4.5.2	
  Configurable	  Options .................................................................................................................................56	
  5.0	
  FIELD	
  DEVICE	  REQUIREMENTS ..............................................................................................................................57	
  5.1	
  Fieldbus	
  Registration.........................................................................................................................................57	
  5.2	
  Support	
  for	
  FOUNDATION	
  Fieldbus	
  Functionality ................................................................................................57	
  5.3	
  Fieldbus	
  Function	
  Blocks ...................................................................................................................................57	
  5.4	
  User	  Application	
  Blocks.....................................................................................................................................59	
  5.4.1	
  Resource	
  Block ...........................................................................................................................................59	
  5.4.2	  Transducer	
  Blocks ......................................................................................................................................60	
  5.4.3	  Function	
  Blocks ..........................................................................................................................................60	
  5.5	
  Control	
  and	
  Data	  Handling ................................................................................................................................62	
  5.5.1	
  Fault	
  Handling ............................................................................................................................................62	
  5.5.2	
  Regulatory	
  Control .....................................................................................................................................63	
  5.5.3	
  Factory	
  Configuration	
  (Basic	
  Ordering	
  Information)..................................................................................64	
  5.6	
  Device	
  Diagnostics.............................................................................................................................................64	
  5.7	
  Field	
  Device	  Power ............................................................................................................................................65	
  5.7.1	  Polarity .......................................................................................................................................................65	
  5.7.2	
  2-­‐Wire.........................................................................................................................................................66	
  5.7.3	
  4-­‐Wire.........................................................................................................................................................66	
  5.7.4	
  Short-­‐circuit	
  Protection ..............................................................................................................................66	
  5.8	
  FOUNDATION	
  Fieldbus	
  Device	
  Requirements	
  for	
  Safety	
  Applications .................................................................66	
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	  - 10 -

September 2012

	
  

6.0	
  SEGMENT	  COMPONENT	  REQUIREMENTS.............................................................................................................68	
  6.1	
  GENERAL ...........................................................................................................................................................68	
  6.2	
  POWER	  SUPPLIES ..............................................................................................................................................68	
  6.2.1	  General.......................................................................................................................................................68	
  6.2.2	
  FOUNDATION	
  Fieldbus	
  Power	
  Supplies .........................................................................................................68	
  6.2.3	
  Bulk	  Power	
  Supplies ...................................................................................................................................68	
  6.2.4	
  FOUNDATION	
  Fieldbus	
  Power	  Conditioner ...................................................................................................69	
  6.3	
  FOUNDATION	
  Fieldbus	
  Terminators .....................................................................................................................70	
  6.4	
  Surge	
  Protection................................................................................................................................................70	
  6.5	
  FOUNDATION	
  Fieldbus	
  Repeaters ........................................................................................................................70	
  6.6	
  FOUNDATION	
  Fieldbus	
  Field	
  Device	  Coupler........................................................................................................71	
  6.7	
  FOUNDATION	
  Fieldbus	
  Cables ..............................................................................................................................71	
  6.7.1	  General.......................................................................................................................................................71	
  6.7.2	
  Existing	
  Wiring............................................................................................................................................72	
  6.7.3	  Spur	  Cables.................................................................................................................................................72	
  6.8	
  On-­‐line	
  Diagnostic	
  Tools....................................................................................................................................72	
  7.0	
  FIELDBUS	
  NETWORK/SEGMENT	  DESIGN	  GUIDELINES ..........................................................................................74	
  7.1	
  FOUNDATION	
  Fieldbus	
  Network/Segment	
  Topology ...........................................................................................74	
  7.1.1	  Point-­‐to-­‐Point	
  Topology .............................................................................................................................74	
  7.1.2	  Tree	  Topology	
  (Chicken	
  Foot) ....................................................................................................................75	
  7.1.3	  Spur	  Topology	
  (Bus	
  with	  Spurs) .................................................................................................................76	
  7.1.4	  Combination	
  Topology ...............................................................................................................................76	
  7.1.5	
  Daisy	
  Chain	
  Topology .................................................................................................................................77	
  7.2	
  FOUNDATION	
  Fieldbus	
  Wiring ..............................................................................................................................78	
  7.2.1	
  Cable	
  Types ................................................................................................................................................78	
  7.2.2	  Distance	  Constraints ..................................................................................................................................78	
  7.2.3	
  Home	  Run	
  Cable	
  (Trunk) ............................................................................................................................78	
  7.2.4	  Spurs...........................................................................................................................................................79	
  7.3	
  FOUNDATION	
  Fieldbus	
  Power,	  Grounding	
  &	
  Lightning	
  Protection ......................................................................79	
  7.3.1	
  Power .........................................................................................................................................................79	
  7.3.2	  Polarity .......................................................................................................................................................80	
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	  - 11 -

September 2012	
  7.3.3	
  Grounding ..................................................................................................................................................80	
  7.3.4	
  Fieldbus	
  Cable	  Shielding.............................................................................................................................81	
  7.3.5	
  Segment	
  Isolation	
  Segregation	  and	  Surge	
  Protection................................................................................86	
  7.3.5.1	
  Isolation...................................................................................................................................................87	
  7.3.5.2	
  Segregation .............................................................................................................................................87	
  7.3.5.3	
  Surge	
  Protectors......................................................................................................................................87	
  7.3.6	  Terminators................................................................................................................................................87	
  7.3.7	
  Repeaters ...................................................................................................................................................88	
  7.4	
  FOUNDATION	
  Fieldbus	
  Segment	
  Risk	  Management.............................................................................................88	
  7.5	
  Segment	  Design	
  Considerations........................................................................................................................89	
  7.5.1	  Multivariable	
  Devices .................................................................................................................................89	
  7.5.2	  Discrete	  Devices .........................................................................................................................................89	
  7.5.3	  Network/Segment	
  Shorting .......................................................................................................................89	
  7.5.4	  Transmitter	
  Assignment .............................................................................................................................89	
  7.5.5	  Multiple	
  Process	
  Variables .........................................................................................................................89	
  7.5.6	  Device	
  Diagnostic	  Alarms ...........................................................................................................................89	
  7.5.7	  Device	  Segregation.....................................................................................................................................90	
  7.5.8	  Combining	
  Safety	  and	
  Control	
  on	
  a	
  Segment.............................................................................................90	
  7.6	
  Limited	
  Power	
  Installations...............................................................................................................................90	
  7.6.1	
  Fieldbus	
  Intrinsically	
  Safe	  Installations.......................................................................................................91	
  7.6.2	
  FISCO ..........................................................................................................................................................91	
  7.6.3	
  FISCO	
  ic	
  (Formerly	
  Known	
  as	
  Fieldbus	
  Non-­‐Incendive	
  Concept	
  (FNICO)	
  Installations ...............................93	
  7.6.4	
  High-­‐power	
  Trunk	
  Installations ..................................................................................................................93	
  7.6.5	
  High-­‐power	
  Trunk	
  with	  Current	
  Limiting	
  Device	  Couplers	
  (Non-­‐Incendive) ..............................................94	
  7.6.6	
  High-­‐power	
  Trunk	
  with	  Isolating	
  Device	  Couplers	
  (Intrinsically	
  Safe)........................................................94	
  7.7	
  FOUNDATION	
  Fieldbus	
  Loading	
  and	  Calculations.................................................................................................94	
  7.7.1	  Spare	
  Capacity............................................................................................................................................94	
  7.7.2	
  Segment	
  Execution	
  Time............................................................................................................................95	
  7.7.3	
  Voltage	
  Drop	  Calculations ..........................................................................................................................96	
  7.7.4	
  Fieldbus	
  Attenuation	
  Calculation .............................................................................................................101	
  7.8	
  FOUNDATION	
  Fieldbus	
  Network/Segment	  Naming	  Convention ........................................................................101	
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September 2012	
  7.8.1	
  Segment	  Naming	  Convention...................................................................................................................101	
  7.8.2	
  Loop	  and	
  Instrument	  Naming	  Convention ...............................................................................................102	
  7.8.3	  Spur	  Naming	  Convention .........................................................................................................................102	
  8.0	
  SITE	  INSTALLATION	  GUIDELINES .........................................................................................................................103	
  8.1	
  Introduction ....................................................................................................................................................103	
  8.2	
  Network	
  Installation........................................................................................................................................103	
  8.2.1	
  Initial	  Cable	  Checkout...............................................................................................................................103	
  8.2.2	
  Cable	  Installation......................................................................................................................................103	
  8.3	
  Fieldbus	
  Segment	
  Commissioning	
  Form .........................................................................................................104	
  8.4	
  Test	  Equipment ...............................................................................................................................................104	
  8.5	
  Installation	
  of	
  FOUNDATION	
  Fieldbus	
  Instruments	
  and	
  Wiring..........................................................................104	
  8.5.1	
  Wiring.......................................................................................................................................................104	
  8.5.2	
  Instrument	
  Ground	
  System ......................................................................................................................105	
  8.5.3	
  Segment	
  Checkout	
  and	  Commissioning ...................................................................................................105	
  9.0.	
  ACCEPTANCE	  TESTING	  REQUIREMENTS.............................................................................................................107	
  9.1	
  Introduction ....................................................................................................................................................107	
  9.2	
  Assumptions....................................................................................................................................................107	
  9.3	
  Device	  Integration	
  Testing	
  Requirements:......................................................................................................108	
  9.4	
  Factory	
  Acceptance	
  Test	  (FAT)	
  Requirements: ...............................................................................................109	
  9.5	
  Site	  Acceptance	
  Testing	
  Requirements...........................................................................................................110	
  9.6	
  Segment	
  Testing/Commissioning	
  Requirements ............................................................................................110	
  9.6.1	
  Segment	
  Testing.......................................................................................................................................110	
  9.6.2	
  Segment	
  Commissioning ..........................................................................................................................111	
  10.0.	
  FOUNDATION	
  FIELDBUS	
  DOCUMENTATION	
  REQUIREMENTS.............................................................................112	
  10.1	
  General..........................................................................................................................................................112	
  10.2	
  Drawings........................................................................................................................................................112	
  10.2.1	
  Segment	
  Drawings .................................................................................................................................112	
  10.2.2	
  Soft	  Data.................................................................................................................................................112	
  10.2.3	
  Location	
  Drawings ..................................................................................................................................113	
  10.3	
  Instrument	
  Index/Database ..........................................................................................................................113	
  10.4	
  Graphics ........................................................................................................................................................113	
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10.5	
  Manufacturer	
  Documentation ......................................................................................................................113	
  APPENDIX	
  1:	
  HOST	  INTEROPERABILITY	  SUPPORT	  TEST.............................................................................................114	
  APPENDIX	
  2:	
  CABLE	  CHARACTERISTICS .....................................................................................................................117	
  A2.1	
  General .........................................................................................................................................................117	
  A2.1.1	
  UL	
  Listing................................................................................................................................................117	
  A2.1.2	
  Temperature	
  Range ...............................................................................................................................117	
  A2.1.3	
  Optional	
  Characteristics.........................................................................................................................117	
  A2.2	
  Characteristic	
  Impedance,	
  Z0........................................................................................................................117	
  A2.3	
  Attenuation...............................................................................................................................................117	
  A2.4	
  Wire ..........................................................................................................................................................117	
  A2.5	
  Shield	  Construction	
  Requirements ...........................................................................................................118	
  A2.6	
  Wire-­‐to-­‐Shield	
  Capacitance	
  Unbalance ....................................................................................................118	
  A2.7	
  Wire	  Twists	  Per	
  Meter ..............................................................................................................................118	
  A2.8	
  Minimum	  Bend	  Radius..............................................................................................................................118	
  A2.9	
  Jacket	
  Resistance ......................................................................................................................................118	
  APPENDIX	
  3:	
  RISK	
  MANAGEMENT ............................................................................................................................119	
  A3.1	
  Process	
  Effect	  Ranking	
  HIGH	  Criteria ............................................................................................................119	
  A3.2	
  Process	
  Effect	  Ranking	
  MEDIUM	  Criteria......................................................................................................119	
  A3.3	
  Process	
  Effect	  Ranking	
  LOW	
  Criteria.............................................................................................................119	
  APPENDIX	
  4:	
  FIELDBUS	
  SEGMENT	  TESTING ..............................................................................................................123	
  A4.1	
   Fieldbus	
  Segment	
  Commissioning	
  Form ......................................................................................................123	
  A4.2	
  Sample	
  Waveforms.......................................................................................................................................124	
  APPENDIX	
  5:	
  FOUNDATION	
  FIELDBUS	
  SEGMENT	  AND	
  LOOP	  DRAWINGS ....................................................................126	
  APPENDIX	
  6:	
  MAINTENANCE	  GRAPHICS ...................................................................................................................131	
  APPENDIX	
  7:	
  ACCEPTANCE	  TESTING	
  PROCEDURES...................................................................................................133	
  A7.1	
  Introduction ..................................................................................................................................................133	
  A7.2	
  Device	  Integration	
  Testing ............................................................................................................................133	
  A7.2.1	
  Functionality	
  Test	  Procedure .................................................................................................................133	
  A7.2.2	
  Device	  Check ..........................................................................................................................................133	
  A7.3	
  Factory	
  Acceptance	
  Testing	
  (FAT).................................................................................................................134	
  A7.3.1	
  H1	
  Interface	  or	
  Linking	
  Device	  Operation ..............................................................................................134	
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September 2012	  A7.3.2	
  Redundancy	
  Switch-­‐over	
  Test	  Procedure ..............................................................................................135	
  A7.3.3	
  Field	
  Device	  Operation...........................................................................................................................135	
  A7.3.4	
  Data	  Reconciliation ................................................................................................................................135	
  A7.3.5	
  Verification	
  of	
  Control	
  Strategies	
  and	  Monitoring.................................................................................136	
  A7.3.5.1	
  Transfer	
  of	
  Data	  to	
  HMI	  or	
  Historian ..................................................................................................136	
  A7.4	
  Site	  Acceptance	
  Testing	
  Requirements.........................................................................................................136	
  A7.5	
  Segment	
  Testing/Commissioning	
  Procedure ................................................................................................136	
  A7.5.1	
  Segment	
  Check ......................................................................................................................................136	
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1.0	
  INTRODUCTION	
  1.1	
  Contents	
  
	
  

	
  

	
  
	
  

	
  

	
  

	
  

	
  

	
  

The FOUNDATION Fieldbus Engineering Guideline is separated into sections. The following is
an explanation of the intent of each chapter:
Section 01 – Introduction
The purpose and scope of the FOUNDATION Fieldbus Engineering Guidelines, references used
to compile FOUNDATION Fieldbus Engineering Guidelines and terms used specifically with
FOUNDATION fieldbus technology.
Section 02 – FOUNDATION Fieldbus Project Requirements
Guidelines for implementing FOUNDATION fieldbus projects.
Section 03 – FOUNDATION Fieldbus Host System Requirements
Functional requirements of the Host system when used to implement FOUNDATION fieldbus
technology.
Section 04 – Software Configuration Guidelines
Information, explanations and guidelines for use when configuring control system software foruse in a strategy that incorporates FOUNDATION fieldbus. Items covered include control module
configuration, function block implementation, condition-based monitoring software
configuration, and alarm management and configuration.
Section 05 – Field Device Requirements
Functional requirements of the field devices when used to implement FOUNDATION fieldbus
technology.
Section 06 – Segment Component Requirements
Functional requirements of the ancillary components such as bulk power supplies, power
conditioners, Fieldbus power supplies, wire, etc., for use with FOUNDATION fieldbus technology
implementation.
Section 07 – Fieldbus Network/Segment Design Guidelines
Information, explanations and guidelines for use when designing FOUNDATION fieldbus
networks/segments, including wiring design. This document will supersede AG-140 Wiring andInstallation Application Guide as well as AG-163 Intrinsically Safe Systems.
Section 08 – Site Installation Guidelines
Information and procedures for use when installing fieldbus networks/segments. Thissection also specifies the procedures required to check out a FOUNDATION fieldbus system,
as well as identifying required tools for use in installing and maintaining FOUNDATION
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September 2012	
  equipment.

	
  

	
  
	
  

Section 09 –Acceptance Test Requirements
Tasks and functions required to perform Device Integration Testing, Factory Acceptance
Testing, Site Acceptance Testing and Segment Testing/Commissioning of a control systemutilizing FOUNDATION fieldbus technology.
Section 10 – FOUNDATION Fieldbus Documentation Requirements
Required documentation for use when designing and maintaining FOUNDATION fieldbus
technology. Documentation such as control philosophy, P&IDs and instrument location
drawings is covered in this chapter.
Appendix 1 Host Interoperability Support Test
Appendix 2 Cable Characteristics
Appendix 3 Shielding Methods
Appendix 4 Risk Management
Appendix 5 Fieldbus Segment Testing Documentation
Appendix 6 FOUNDATION Fieldbus Segment and Loop Drawings
Appendix 7 Maintenance Graphics
Appendix 8 Acceptance Testing Procedures

1.2	
  Purpose	
  

	
  

	
  

The FOUNDATION Fieldbus System Engineering Guideline is intended to compliment the
principal’s instrument specifications. It details how fieldbus devices are specified, installed,
configured, commissioned, which are different than conventional analog or "smart"
instruments.
This Engineering Guideline addresses the implementation of FOUNDATION fieldbus only. Other
fieldbus technologies exist that may be integrated into the basic process control system, if theengineering design requires. FOUNDATION fieldbus is primarily used to replace the traditional
analog input/output signal types, but is also used with discrete devices such as on/off valvesand electric actuators. Moreover, FOUNDATION fieldbus transmitters often take the place ofprocess switches. FOUNDATION fieldbus technology is chartered by the Fieldbus Foundation.

1.3	
  Scope	  This document will provide the definition of the design, specification, installation, configuration,commissioning for a FOUNDATION fieldbus-based control systems. A second Application Guide
will be developed to define the Operation, Maintenance, and Asset Management ofRevision 3.2.1
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September 2012	  FOUNDATION fieldbus-based control systems.

	
  

	
  

	
  

This guideline will only discuss the voltage mode (parallel coupling) medium attachment unit,
as defined in IEC 61158-2, operating at a signal speed of 31.25 k/bits per second (i.e., H1).
FOUNDATION fieldbus systems include instruments and hosts that cover all applications andaspects of instrumentation and control. Therefore, it is intended that all FOUNDATION
instrumentation and control system standards apply to FOUNDATION fieldbus systems, except
as noted herein.
This revision of the specification does not yet provide specific, recommended practices for the
installation and use of FOUNDATION Fieldbus for Safety Instrumented Functions (FF-SIF), sinceactual installations are not yet fully implemented. Preliminary discussions of some of therequirements and potential practices are provided.
Subject to the disclaimer at the front of this document, this Engineering Guideline applies to
end-users, contractors and control system vendors.

1.3.1	  General	
  FOUNDATION fieldbus creates an Automation Infrastructure by using an all-digital, two-way
multi-drop communications link among intelligent smart field devices and automation systems.
FOUNDATION fieldbus is the Local Area Network (LAN) for instruments used in process
automation with built-in capability to distribute the control application across the network.
1.3.2	
  Project	  Consideration	
  

	
  

As with any new project, it is critical that the right skill sets be brought forth for the project. The
same is true for a fieldbus project. Experience has shown that training of all members of the
project team, engineers, maintenance personnel, and operations staff is critical to the projectsuccess. This training should be provided at the “front end” of the project to minimize reworkand through different stages of the project as project members come on board, in order tobenefit from information gained through “experience.”
Bringing in the right consultants at key junctures in the project to review and advise on the next
steps is also often a prudent investment.

1.4	
  References	
  1.4.1	
  FOUNDATION	
  Fieldbus	
  Specifications	
  1.4.1.1
1.4.1.2
1.4.1.3
1.4.1.4
1.4.1.5

FF-569 Host Interoperability Support Test Profile and Procedures
FF-831 Fieldbus Power Supply Test Specification
FF-844 H1 Cable Test Specification
FF-846 Device Coupler Test SpecificationFF- 912 Field Diagnostic Profile

1.4.2	
  Industry	
  Codes	
  and	
  Standards	
  1.4.2.1
Revision 3.2.1
	  IEC 61158-1: Introductory Guide- 18 -

September 2012	
  1.4.2.2
1.4.2.3
1.4.2.4
1.4.2.5
1.4.2.6
1.4.2.7

	
  

	
  

1.4.2.8
1.4.2.9

IEC 61158-2: Physical Layer Specification and Service Definition
IEC 61158-3: Data Link Layer (DLL) Service Definition
IEC 61158-4: Data Link Layer (DLL) Protocol Specification
IEC 61158-5: Application Layer Service Specification
IEC 61158-6: Application Layer Protocol Specification
1.4.2.9 CEI/IEC 61508: Functional Safety of Electrical/Programmable
Electronic Safety-Related Systems
CEI/IEC 61511: Functional Safety – Safety Instrumented Systems for theProcess Industry Sector
NAMUR NE91: Requirements for Online Plant Asset Management System
NAMUR NE107: Self-monitoring and Diagnosis of Field Devices

Note that the parts dealing with the DLL and the Application Layer contain parallel sections foreight different protocols, including FOUNDATION fieldbus.
De-facto standards are available from the Fieldbus Foundation that will comply with and becompatible with the IEC 61158 suite of standards.

1.4.3	  Other	  References	  For further references, visit the Fieldbus Foundation website (www.fieldbus.org) and navigate
to the “End User Resources” section.

1.5	
  Definitions	
  1.5.1	  General	
  Definitions	
  
	
  

	
  
	
  

	
  

	
  
	
  
	
  

The definitions below shall be included if the words defined are used in the Code of Practice.
The contractor is the party that carries out all or part of the design, engineering, procurement,
construction, commissioning or management of a project, or operation or maintenance of a
facility.
The manufacturer/supplier is the party that manufactures or supplies equipment and services
to perform the duties specified by the contractor.
The principal is the party that initiates the project and ultimately pays for its design andconstruction. The principal will generally specify the technical requirements. The principal may
also include an agent or consultant authorized to act for, and on behalf of, the principal. The
principal may undertake all or part of the duties of the contractor.
The words shall/must/will indicate a mandatory requirement.
The word should indicates an acceptable recommended course of action or feature based on
past project implementations.
The words may/can indicate one acceptable course of action.

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September 2012	
  1.5.2	
  FOUNDATION	
  Fieldbus	
  Definitions	
  

	
  
	
  

	
  
	
  

	
  

	
  

	
  
	
  

	
  
	
  
	
  

	
  
	
  

The following represent definitions of terms commonly encountered in the use and applicationof FOUNDATION technology. A comprehensive list of definitions related to FOUNDATION fieldbus
can be found on the Fieldbus Foundation web site at http://www.fieldbus.org.

A
Acyclic Period
Also known as background traffic or unscheduled communication, the acyclic period is that
portion of the communication cycle time during which information other than Publish/Subscribe
data is transmitted. Typical information transmitted during this time includes Alarms/Events,
Maintenance/ Diagnostic information, Program Invocations, Permissives/Interlocks, Display
information, Trend Information and Configuration.	
  Application Layer
A layer in the communication stack containing the object dictionary.
Automation System
A process automation, control, and diagnostic system composed of distinct modules. These
modules may be physically and functionally distributed over the plant area. The automation
system contains all the modules and associated software required to accomplish the regulatory
control and monitoring of a process plant. This definition of automation system excludes field
instruments, remote terminal units, auxiliary systems and management information systems.
Auto Sense
Capability by the system to automatically detect and recognize any hardware upon addition toor removal from the system without any user intervention.
Auxiliary System
A control and/or monitoring system that is stand-alone, performs a specialized task, andcommunicates with the automation system.

B
Basic Device
A Basic Device is any device not having the capability to control communications on an H1fieldbus segment.
Brick
See Device CouplerBus
A H1 FOUNDATION fieldbus cable between a Host and field devices connected to multiple
segments, sometimes through the use of repeaters.

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C
Capabilities FileA Capabilities File describes the communication objects in a fieldbus device. A configuration
device can use Device Description (DD) Files and Capabilities Files to configure a fieldbus
system without having the fieldbus devices online.
Common File Format (CFF) FileAn ASCII text file used by the Host to know the device detailed fieldbus capabilities without
requiring the actual device. This file format is used for Capabilities and Value Files.
Communications Stack
Layered software supporting communication between devices. A Communications Stack is
device communications software, which provides encoding and decoding of User Layer
messages, deterministic control of message transmission, and message transfer.
Configurable
The capability to select and connect standard hardware modules to create a system; or thecapability to change functionality or sizing of software functions by changing parameters
without having to modify or regenerate software.
Configuration
The physical installation of hardware modules to satisfy system requirements; or the selectionof software options to satisfy system requirements.
Connector
A Connector is a coupling device used to connect the wire medium to a fieldbus device or toanother segment of wire.
ConsoleA collection of one or more workstations and associated equipment such as printers andcommunications devices used by an individual to interact with the automation system andperform other functions.
Control Loop
A Control Loop is a group of Function Blocks (FBs) that execute at a specified rate within a
FOUNDATION fieldbus device or distributed across the fieldbus network.
Cycle
The scanning of inputs, execution of algorithms and transmission of output values to devices.

D
DART (Dynamic Arc Recognition and Termination)
DART technology enables intrinsic safety of an electric circuit with dramatically increased
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	  - 21 -

September 2012	
  available power during normal operation. In the case of an unwanted, potentially threatening
condition such as opening or closing of the electric circuit, DART technology puts the circuit into
a safe state before critical levels are reached. A spark caused by opening or closing an electric
circuit has a very characteristic and easily detectable change of current and voltage. Thischange is detected by DART technology and the circuit is switched off in only a few
microseconds (µs). Thus, even at higher power levels sparks never become incendive.
Pepperl+Fuchs in conjunction with PTB, the Physikalisch Technische Bundesanstalt inGermany and twelve other manufacturers is involved in introducing changes to international
standard IEC 60079 . In order to facilitate easier practical application (e.g., interoperability
between manufacturers) the working group targets introducing regulations for test and approvalof dynamically acting power supplies and equipment into IEC 60079.

	
  

	
  

	
  

	
  

	
  
	
  

	
  
	
  

	
  

Data Link Layer (DLL)The Data Link Layer (DLL) controls transmission of messages onto the fieldbus, and manages
access to the fieldbus through the Link Active Scheduler (LAS). The DLL used by FOUNDATION
fieldbus is defined in IEC 61158. It includes Publisher/Subscriber, Client/Server andSource/Sink services.
Deterministic
Ability to measure the maximum worst-case delay in delivery of a message between any two
nodes in a network. Any network protocol that depends on random delays to resolve
mastership is nondeterministic.
Device Coupler
A device coupler is a physical interface between a trunk and spur, and a device.
Device Description (DD)A Device Description (DD) provides an extended description of each object in the Virtual Field
Device (VFD), and includes information needed for a control system or Host to understand themeaning of data in the VFD.
Discrete Control
Control where inputs, algorithms, and outputs are based on logical (yes or no) values. In thecase of FOUNDATION fieldbus, discrete includes any integer operation between 0-255.
DI
Discrete Input – the signal is from the field device to the Host system or another field device.
DO
Discrete Output – the signal is generated by the Host system or another field device andtransmitted to a field device..

E
EDDL
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Electronic Device Description Language (see www.eddl.org)
Ethernet
Physical and data link layer defined by IEEE 802 standards used by FOUNDATION fieldbus HSE.

F
Factory Acceptance Test (FAT)The final test at the vendor's facility of the integrated system being purchased.
Fieldbus
A Fieldbus is a digital, two-way, multi-drop communication link among intelligent measurement
and control devices. It serves as a Local Area Network (LAN) for advanced process control
remote input/output applications.
Fieldbus Access Sublayer (FAS)
The Fieldbus Access Sublayer (FAS) maps the Fieldbus Message Specification (FMS) onto
the Data Link Layer (DLL).
Fieldbus Messaging Specification (FMS)The Fieldbus Messaging Specification (FMS) contains definitions of Application Layer services
in FOUNDATION fieldbus. The FMS specifies services and message formats for accessing
Function Block (FB) parameters, as well as Object Dictionary (OD) descriptions for thoseparameters defined in the Virtual Field Device (VFD).
Commentary:
Network Management (NM) permits FOUNDATION fieldbus Network Manager (NMgr) entities to
conduct management operations over the network using Network Management Agents (NMAs).
Each NMA is responsible for managing the communications within a device. The NMgr and
NMA communicate through use of the FMS and Virtual Communications Relationship (VCR).
FISCO
Fieldbus Intrinsic Safe COncept. Allows more power to an IS segment for approved FISCO
devices, enabling more devices per IS segment. The newest editions of the IEC standards
specify that FISCO 'ia' is suitable for Zones 0, 1 and 2; FISCO 'ib' can be used in Zones 1 and
2; and FNICO can be applied in Zone 2. FNICO, the Fieldbus Non-Incendive COncept, allows
more power to a fieldbus segment in a Zone 2 Area, thus enabling more devices per segment
than is possible with a FISCO solution. It should be noted that FNICO is now known as FISCO‘ic’.
Commentary:
FISCO eliminates the requirement of calculating entity parameters of capacitance andinductance when designing networks.
Flexible Function Block (FFB)
A Flexible Function Block (FFB) is similar to a Standard FB, except that an application-specific
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algorithm created by a programming tool determines the function of the block, the order anddefinition of the block parameters, and the time required to execute the block. FFBs are
typically used for control of discrete processes and for hybrid (batch) processes. A
Programmable Logic Controller (PLC) can be modeled as a Flexible Function Block device.

G
Gateway	
  Translates another protocol to FOUNDATION fieldbus or vice versa, for example HART to
FOUNDATION fieldbus or Modbus to FOUNDATION fieldbus.

H
H1
H1 is a term used to describe a FOUNDATION fieldbus network operating at 31.25 kbit/second.
H1 Field Device
An H1 Field Device is a fieldbus device connected directly to an H1 FOUNDATION
fieldbus. Typical H1 Field Devices are valves and transmitters.
H1 Repeater
An H1 Repeater is an active, bus-powered or non-bus-powered device used to extend therange over which signals can be correctly transmitted and received for a given medium. A
maximum of four Repeaters and/or active Couplers can be used between any two devices
on an H1 FOUNDATION fieldbus network. Repeaters connect segments together to form
larger networks.
High Speed Ethernet (HSE)High Speed Ethernet (HSE) is the Fieldbus Foundation's high-speed control network
running Ethernet and IP. FOUNDATION HSE can have the same Function Blocks as H1 andwill be the technology of the wireless backhaul network.
Host
Control system that has FOUNDATION fieldbus capabilities to configure and operate FOUNDATION
fieldbus segments. There are several classes of Host systems:
Class
61	
  
Class
62	
  
Class
63	
  
Class
64	
  
Class
71	
  

Integrated Host	
  Visitor Host	  Bench Host	  Bench host	  SafetyIntegrated Host	
  Revision 3.2.1
	  Primary, on process Host that manages the communication and application
configuration of all devices on a network.	
  Temporary, on process Host with limited access to device parameterization.	
  Primary, off process Host for configuration and setup of a non-commissioned
Device	  Primary, off process Host with limited access to device parameterization of an offline, commissioned device.	
  (PRELIMINARY) Primary, on-process Host that manages the communication andapplication configuration of all safety and control & monitoring devices on a network.	
  - 24 -

September 2012	  Host Profile Registration
The Fieldbus Foundation has been doing Host testing since its earliest days. Over the years,
this process has evolved considerably. The Fieldbus Foundation's previous Host Interoperability
Support Test (HIST) provided a host test protocol with no provision for formal productregistration. With HIST, all the work was done by the Host vendor. It soon became clear,
however, that testing and registration of Hosts was necessary. That’s when the foundation
introduced our Host Profile Registration Process.
Under the new Host Profile Registration Process, the foundation conducts functional testingwith a test device and specialized test Device Descriptions (DDs) and Capabilities Files (CFs).
Registered devices from different vendors are also used during testing. The Host profile under
test must support a clear set of required features. A Host will conform to some, or perhaps all,features as defined by the Host feature checklist. However, because Hosts can have various
definitions, not all features may be applicable to a Host implementation. Therefore, it is notexpected that every Host should support each feature.
Each feature contains a set of test procedures that are to be run against the Host or the fieldbus
system using the Host. In order for a Host to claim conformance to the feature, the Host must
be able to pass the test procedures defined by the feature. The features themselves are
generic; therefore, manufactures will derive test cases, or actual implementation steps
necessary to meet the requirements of the test procedure. Fieldbus Hosts successfullycompleting the test requirements are authorized to bear the official FOUNDATION productregistration symbol.

	
  

	
  

HSE Device
An HSE Device is a FOUNDATION fieldbus device connected directly to High Speed
Ethernet (HSE). Typical HSE Field Devices are HSE Linking Devices, HSE Devices
running Function Blocks (FBs), and Host Computers.
HSE Linking Device
An HSE Linking Device is a device used to interconnect FOUNDATION fieldbus H1 fieldbus
networks/segments to High Speed Ethernet (HSE) to create a larger system.
HSE Switch
An HSE Switch is standard Ethernet equipment used to interconnect multiple High Speed
Ethernet (HSE) devices such as HSE Linking Devices and HSE Field Devices to form a larger
HSE network.
	
  

	
  

Input/Output (I/O) Subsystem Interface
An Input/Output (I/O) Subsystem Interface is a device used to connect other types ofcommunications protocols to a fieldbus segment or segments. Refer also to Gateway.
Interchangeability
Interchangeability is the capability to substitute a device from one manufacturer with that of
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another manufacturer on a fieldbus network without loss of functionality or degree of
integration.
Instantiable
The ability of Function Blocks (FBs) to create multiple tagged FBs of different types from alibrary as required by the application. Quantity per device is restricted by device memory andother resources.
Interoperability
Interoperability is the capability for a device from one manufacturer to interact with that ofanother manufacturer on a fieldbus network without loss of functionality.
IS
Intrinsic Safety
ITK
Interoperability Test Kit used by the Fieldbus Foundation to register devices and confirm
compliance with the relevant FOUNDATION fieldbus standards. This is a pass/fail test. Only
devices passing the full suite of tests receive the official FOUNDATION registration "tick mark."

J
K
	
  

	
  

	
  

	
  

L
Link
A Link is the logical medium by which FOUNDATION fieldbus H1 fieldbus devices areinterconnected. It is composed of one or more physical segments interconnected by bus,
Repeaters or Couplers. All of the devices on a link share a common schedule, which isadministered by that link's current LAS. It is the Data Link Layer name for a network.
Link Active Scheduler (LAS)A Link Active Scheduler (LAS) is a deterministic, centralized bus scheduler that maintains a listof transmission times for all data buffers in all devices that need to be cyclically transmitted.
Only one Link Master (LM) device on a FOUNDATION fieldbus H1 Fieldbus Link can befunctioning as that link's LAS.
Link Master (LM)A Link Master (LM) is any device containing Link Active Scheduler (LAS) functionality that cancontrol communications on a FOUNDATION fieldbus H1 Fieldbus Link. There must be at least
one LM on an H1 Link; one of those LM devices will be elected to serve as LAS.
Link Objects
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A Link Object contains information to link Function Block (FB) Input/Output (I/O) parameters inthe same device and between different devices. The Link Object links directly to a Virtual
Communications Relationship (VCR).

M
MAC Address
A unique hardware address given to each Ethernet interface chip.
Macrocycle
The repetitious scheduling of the Function Block within all the devices on a segment. The LAS
is responsible for scheduling of the segment macrocycle.
Methods
Methods appear in system software as step-by-step “wizards.” Methods are an optional (buthighly desirable) addition to Device Descriptions (DDs). Methods are used to define/automate
procedures (such as calibration) for operation of field devices.
Mirror Function BlockSee Shadow BlockMulti-bit Alert Support
The capability to utilize the multi-bit alarm capability. Multi-bit alarms are generated when
multiple alerts or alarms occur within the same field device.
ModeControl block operational condition, such as manual, automatic, or cascade.

N
Network
A network as applied in this document is the termination of one or more fieldbus segments
into an interface card of the Host system.
Commentary:
In this document, as has become industry practice, the term “segment” is used to represent acable and devices installed between a pair of terminators.
Network Management (NM)Network Management (NM) permits FOUNDATION fieldbus Network Manager (NMgr) entities to
conduct management operations over the network by using Network Management Agents(NMAs). Each Network Management Agent (NMA) is responsible for managing thecommunications within a device. The NMgr and NMA communicate through use of theFieldbus Messaging Specification (FMS) and Virtual Communications Relationship (VCR).
Noise AV
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Average noise in the network during the silence period between frames.

O
Object Dictionary
An Object Dictionary (OD) contains all Function Block (FB), Resource Block (RB) andTransducer Block (TB) parameters used in a device. Through these parameters, the blocks
may be accessed over the fieldbus network.
OPC (OPen Connectivity – formerly Object Linking and Embedding for Process Control)
Software application allowing bi-directional data flow between two separate applications.
These applications may be running on the same or on separate servers.
OfflinePerform tasks while the Host system is not communicating with the field devices.
OnlinePerform tasks (configuration, etc.) while the Host system is communicating with the fielddevices.
Operator Console
A console used by an operator to perform the functions required to monitor and control his
assigned units.

P
Physical Layer
The Physical Layer receives messages from the Communications Stack and converts themessages into physical signals on the fieldbus transmission medium, and vice-versa.

Q
Quiescent Current
The device power consumption or, the current drawn while the device is not transmitting. The
current should be as low as possible to enable more devices and long wire lengths, particularly
in intrinsic safety.

R
Redundant Configuration
A system/subsystem configuration providing automatic switchover, in the event of a failure,
without loss of a system function.

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Regulatory Control
The functions of process measurement, control algorithm execution, and final control device
manipulation that provide closed loop control of a plant process.
Resource Block (RB)A Resource Block (RB) describes characteristics of the fieldbus device such as the device
name, manufacturer and serial number. There is only one Resource Block (RB) in a device.

S
Schedules
Schedules define when Function Blocks (FBs) execute and when data and status is publishedon the bus.
Segment
A Segment is a section of a FOUNDATION fieldbus H1 fieldbus terminated in its characteristic
impedance. Segments can be linked by Repeaters to form a longer H1 fieldbus. Eachsegment can include up to 32 H1 devices.
Commentary:
In this document, as has become industry practice, the term “segment” is used to represent acable and devices installed between a pair of terminators. The FOUNDATION fieldbus
specifications use the term “network” to describe the system of devices. This document uses
these terms “interchangeably.”
See ANSI/ISA–50.02, Part 2 (IEC 61158-2): SEGMENT = The section of a fieldbus terminatedin its characteristic impedance. Segments are linked by repeaters to form a complete fieldbus.
Several communication elements may be connected to the trunk at one point using a multi-port
coupler. An active coupler may be used to extend a spur to a length that requires termination to
avoid reflections and distortions. Active repeaters may be used to extend the length of thetrunk beyond that of a single segment as permitted by the network configuration rules. A fully
loaded (maximum number of connected devices) 31.25 kbit/s voltage-mode fieldbus segment
shall have a total cable length, including spurs, between any two devices, of up to 1,900 m.
There shall not be a non-redundant segment between two redundant segments.
Self-Diagnostic
Capability of an electronic device to monitor its own status and indicate faults that occur within
the device.
SpliceA Splice is an H1 Spur measuring less than 1 m (3.28 ft.) in length.
Shadow Block
A shadow Function Block is set up in the centralized controller to mirror the data associatedwith an external Function Block located in an external device. The control routine of thecentralized controller communicates with the external Function Block via the shadow Function
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Block as if the external Function Block was being implemented by the centralized controller.
The shadow Function Block automatically obtains current information associated with theexternal Function Block. In the case of a fieldbus protocol, this communication is accomplishedusing both synchronous and asynchronous communications. However, the shadow Function
Block communicates with other Function Blocks within the centralized controller as if theexternal Function Block is being fully implemented by the centralized controller.
Spur
A Spur is an H1 branch line connecting to the Trunk that is a final circuit. A Spur can vary inlength from 1 m (3.28 ft.) to 120 m (394 ft.).
Standard Function Block (FB)
Standard Function Blocks (FBs) are built into fieldbus devices as needed to achieve thedesired control functionality. Automation functions provided by Standard FBs include Analog
Input (AI), Analog Output (AO) and Proportional/Integral/Derivative (PID) control. The
Fieldbus Foundation has released specifications for 21 types of Standard FBs. There can be
many types of FBs in a device. The order and definition of Standard FB parameters are fixedand defined by the specifications.
Stack
A set of hardware registers or a reserved amount of memory used for calculations or to keep
track of internal operations. Note: This is different than the Communications Stack defined
above.
Stack Test
Testing of the Communications Stack to show that the device communicates when it should
and stays silent when it should, as well as making sure that the device package messages
properly.
Rate/Stale Count
This is a number corresponding to the allowable missed communications before a device willshed its control mode, as specified in the Function Block Application Process (FBAP). This isbasically a Watchdog Timer.
System Management (SM)
System Management (SM) synchronizes execution of Function Blocks (FBs) and thecommunication of Function Block (FB) parameters on the fieldbus, and handles publication of
the time of day to all devices, automatic assignment of device addresses, and searching forparameter names or "tags" on the fieldbus.

T
Tag
A tag identifies a physical device (PD_TAG) or a block (FB_TAG). Each tag is unique.
Terminator
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Impedance-matching module used at or near each end of a transmission line that has thesame characteristic impedance of the line. Terminators are used to minimize signal distortion,
which can cause data errors. H1 terminators also have another even more important function.
They convert the current signal transmitted by one device to a voltage signal that can bereceived by all devices on the network.
Topology
Shape and design of the fieldbus network (e.g., tree branch, daisy chain, point-to- point,
bus with spurs, etc.).
Transducer Block (TB)
A Transducer Block (TB) decouples Function Blocks (FBs) from the local Input/Output (I/O)
functions required to read sensors and command output hardware. Transducer Blocks (TBs)
contain information such as calibration date and sensor type. There is usually one TB channel
for each input or output of a Function Block (FB). Some devices may also include additional
Transducer Blocks for configuring local displays and/or for specialized diagnostics.
Transmitter
A Transmitter is an active fieldbus device containing circuitry, which applies a digital signal on
the bus.
Trunk
A Trunk is the main communication highway between devices on a FOUNDATION fieldbus H1
network. The Trunk acts as a source of main supply to Spurs on the network.

U
User Application
The User Application is based on "blocks," including Resource Blocks (RBs), Function Blocks(FBs) and Transducer Blocks (TBs), which represent different types of application functions.
User Layer
The User Layer provides scheduling of Function Blocks (FBs), as well as Device Descriptions(DDs), which allow the host system to communicate with devices without the need for custom
programming.

VViews
A mechanism used in Client/Server communications to pass a logical block of related
information between two devices on the network as a means to reduce network traffic whilestill providing data in a timely fashion.
Virtual Communication Relationship (VCR)
Configured application layer channels that provide for the transfer of data between
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applications. FOUNDATION fieldbus describes three types of VCRs: Publisher/Subscriber,
Client/Server and Source/Sink. Knowledge of VCRs is generally not required for newer
systems that are available today.
Virtual Field Device (VFD)A Virtual Field Device (VFD) is used to remotely view local device data described in
the object dictionary. A typical device will have at least two VFDs.

W
WizardA Wizard is a means of automating procedures in Microsoft Windows™. Wizards canbe used to implement methods.
Workstation
A set of electronic equipment including, at a minimum, one monitor, keyboard(s) andassociated pointing device(s).

X
YZ

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1.6	
  Abbreviations	
  
	
  

	
  
Abbreviations

Description

AI

Analog Input

AO

Analog Output

BPCS

Basic Process Control System

BPS

Bulk Power Supply

CAPEX

Capital Expenditure

CCR

Central Control Room

C/SClient/Server

CiF

Control in the Field

CFF

Common File Format

DCS

Distributed Control System/Digital Control System

DI

Discrete Input

DD

Device Description

DLL

Data Link Layer

DO

Discrete Output

DTM

Device Type Manager

EDDLElectronic Device Description Language

ESD

Emergency Shut Down

FAR

Field Auxiliary RoomFAS

Fieldbus Access Sublayer

FB

Function Block

FDT

Field Device ToolFF

FOUNDATION Fieldbus

FF-SIF

FOUNDATION Fieldbus for Safety Instrumented
Functions

FFB

Flexible Function BlockFFPS

FOUNDATION Fieldbus Power Supply

F&G

Fire and Gas

HIST

Host Interoperability Support Testing

HMI

Human Machine Interface

HSE

FOUNDATION High Speed Ethernet

IEC

International Electrotechnical Commission

I/O

Input Output

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Abbreviations

Description

IPF

Instrument Protective Function

IS

Intrinsic Safety

IT

Information Technology

ITC

Instrument Tray Cable

ITK

Interoperability Test Kit

LASLink Active Schedule

LM

Link Master

MAI

Multi Analog Input

MAO

Multi Analog Output

ML

Manual Loader

MOV

Motor Operated ValveMV

Manipulated Variable (controller output)

NM

Network Management

OD

Object Dictionary

OPEX

Operational Expenditure

PCS

Process Control System

PAS

Process Automation System

P/S

Publish/Subscribe

PD

Proportional/Derivative Control

P&ID

Process & Instrumentation Diagram

PID

Proportional/Integral/Derivative Control

PTB

Physikalisch-Technische Bundesanstalt

PV

Process Variable

PLC

Programmable Logic Controller

RA

Ratio

RB

Resource Block

SIF

Safety Instrumented Function

SIS

Safety Instrumented System

SIL

Safety Integrity Level

SM

System ManagementSP

Set PointSS

Safety Systems

TB

Transducer Block

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Abbreviations

Description

TCO

Total Cost of Ownership

TPE

Thermo Plastic Elastomer

VCR

Virtual Communication Relationship

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2.0	
  FOUNDATION	
  FIELDBUS	
  PROJECT	
  REQUIREMENTS	
  2.1	
  Introduction	
  

	
  

	
  

	
  

Proper utilization of FOUNDATION fieldbus technology in projects requires the following changes
compared to traditional technologies for connection of field devices:•

Field devices and segments become an integral part of the DCS. This requires
an integrated configuration, data management, and system architecture
approach to field network design.

•

System integration aspects of FOUNDATION fieldbus require some design
activities to be performed earlier and with greater detail in the project lifecycle.

•

More advanced functions are achieved in FOUNDATION fieldbus designs
compared to traditional technologies. These advanced functions offer
considerable opportunities for operating cost-saving and improved
commissioning and start-up.

•

System, field device, and segment component testing processes are moreadvanced than for simple analog connections.

•

Traditional lines of authority between crafts and legacy-derived practices should
be reviewed to determine if they are a suitable “fit” for FOUNDATION fieldbus.

	
  

	
  

2.2	
  Use	  of	
  Approved	
  Products	
  

	
  

Project staff shall utilize systems, field devices, and segment components that have passed
rigorous approval processes. These processes include:••••

Release testing by the vendor
FOUNDATION fieldbus tests (HIST, ITK – where applicable)
Host system vendor integration tests
Device Integration Tests (specific system and device combinations)2.3	
  Early	
  in	
  the	
  Project	
  2.3.1	
  Project	
  Evaluation	  Document the anticipated use of FOUNDATION fieldbus. State where it can be used and where
it is not yet appropriate. This document can be in report form, risk analysis or other formats.
Document such areas as: What benefits are expected Are they realistic based on experience?
 Can they be realized by the project?
 Can they be realized during the project schedule?
 What obstacles may be expected? Can they be resolved?
 What is the TCO (Total Cost of Ownership) on the project?
• Should the project use conventional technologies in conjunction with	
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

FOUNDATION fieldbus?
Brainstorm the following:• Installation savings (schedule and cost)• Engineering (tools, schedule and cost)• Diagnostic tools (will they be useful and used during the project lifecycle?)• Maintenance (how to use FOUNDATION fieldbus to its greatest advantage)• Installation (things do go wrong during construction)• Maintenance• Operations• Enterprise2.3.2	  Training	
  Plan for and provide training for all necessary personnel at this stage of the project.
• Plan for all phases (e.g., design, system implementation, installation,commissioning and operation)• Implement appropriate early training (include O&M, Management, etc.)
Training is available from the Fieldbus Foundation, Fieldbus Foundation Certified Training
Centers, other training centers and Host or Device suppliers. A combination of these training
sources may be appropriate.
2.3.3	
  Implementation	
  Basis	  A well-defined Implementation Basis for the use of FOUNDATION fieldbus on the project willserve to keep the project on track (especially if it is a long-term effort). All parties involved(owner, engineering, equipment suppliers, contractors, etc.) will have the same expectationand design basis to work from.
• Prepare sound, clear design basis• Follow that basis• Keep current with the technology
2.3.4	
  Host	  Selection	  Correct Host selection for the project is a key element to the success of the project. Many
projects tend to base major emphasis on cost of the DCS system only. The use of
FOUNDATION fieldbus now means that the Host (DCS) and field devices are one system.
Evaluation should incorporate as much of this concept as possible. Base the technicalselection on at least the following:• FOUNDATION fieldbus project capability• FOUNDATION fieldbus architecture (controller input or HSE)	
  • Host vendor’s project experience with FOUNDATION fieldbus (complexity andsize of projects, etc.)• Ease of use• Integration of Asset Management System• Simulation capability for design and FAT• System diagnostics available• Local support capability• Device integration capability	
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•

	
  

Training capability

2.3.5	  Component	  Selection	  As with the Host selection, all field devices may not have the same capabilities, which aredefined as needed in the Project Implementation Basis. Base the technical selection on
the following:• Meets area class requirements?
• How does it work individually?
• How does it work with other devices?
• How easy to configure?
• Does it perform as published?
• Proven track record?
• Integration with Host system(s)?
• Support for EDDL and/or FDT/DTMs?

	
  
The	
  following	
  points	
  should	
  be	
  considered	
  as	
  differentiators	
  for	
  FOUNDATION	
  fieldbus	
  devices:	
  • Function	
  block	
  types	  	
  • Function	
  block	
  execution	
  time	  	
  • Diagnostics	
  capability	  	
  • Current	
  consumption	  	
  • LAS	
  capable	  	
  • Firmware	
  download	
  capable	
  	
  
	
  
Buy	
  a	
  device	
  that	  fits	  your	  application	
  requirements.	
  More	  features	
  do	
  not	
  always	
  equal	  better	  functionality	
  or	
  a	
  better	
  fit	
  for	
  your	  application.	
  	
  2.3.6	  Work	  Processes	
  Define any new or revised work processes, which may be required because of the use of
FOUNDATION fieldbus. This is one of the most often overlooked aspects of a fieldbus project. If you
do not pay attention to proper work processes, the people that need the data from fieldbus devices
may not be able to get it, or you could remain stuck in traditional maintenance processes that are
essentially transformed by fieldbus. Fieldbus is essentially a data pipeline, and users must plan
where that flood of data is going to go and how it will be transformed into useful information. In
most cases today, this is a secondary consideration that is only addressed after the system is up
and running. Having a team in place consisting of personnel from all areas of the plant that are
affected will expedite this process. What kinds of information are your maintenance personnel
looking for? What about data storage and validation concerns for companies that must undergo
regulatory compliance in industries such as pharmaceuticals and food & beverage?

	
  
	
  

The information flow from the device level to the associated applications that need it must be
mapped out prior to startup to achieve maximum benefits. Intelligent field devices are really dataservers, and much of the information in these data servers is not appropriate for the control system
operator. If you are dealing with a supplier that has an effective fieldbus configuration tool
integrated with a good Plant Asset Management (PAM) application, it should be a minimal effort to
get the right information to the right people at the right time.
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  2.3.7	  Division	
  of	
  Responsibility	
  Define Divisions of Responsibility between Owner, Engineer, Host and device suppliers,
construction, etc.
2.3.8	  Integration	
  Tools	
  between	  Offices	
  Confirm or develop integration tools, which will be used by the different parties involved in the
project (this is not unique to the use of FOUNDATION fieldbus).
2.3.9	  Integration	
  with	  Suppliers	
  Determine how much involvement suppliers will have in the design, purchase, installation andtraining of the FOUNDATION fieldbus portion of the project.
2.3.10	
  Device	  Integration	
  Testing	  Project staff should not assume that any FOUNDATION fieldbus device, in combination with any Host
system, will provide full functionality of all advertised features of the Device or System. Project staff
should utilize test or development systems as early as possible during the project design phase toensure device integration. Typical configurations of hardware and software shall be thoroughly
tested before high volume replication. These tests should not be postponed until FAT. Some
examples of integration test procedures are given in Appendix 8. The device integration testing canbe done at any one or a combination of the following:• At the EPC’s facility• At the Host supplier• Project office or Centre Of Excellence• Third-party laboratory (Fieldbus Foundation certified)Interoperability testing for Devices and Hosts provides a base level of testing, but it is impossible totest every permutation of every Device and Host with every other Device or Host. Theinteroperability test provides a basic level of testing. Additional features may require additional
testing.

	  FAT shall utilize simulated I/O, including FOUNDATION fieldbus I/O, if the Host systems support
adequate simulation. In that case, field devices are not required at FAT.
Appendix 5 gives examples of field tests procedures for FOUNDATION fieldbus Devices andSegments. These procedures are generally covered in more depth in other documents. They
shall be planned for execution during the design phase and may be tested during integration
tests described in Appendix 8.

2.4	
  During	
  Project	  Design	
  2.4.1	  Training	
  (more,	  detailed)	
  Plan for and provide training for all necessary personnel at this stage of the project.
 Engineering Construction
 Owner/End User	
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  2.4.2	
  Risk	  Assessment	
  Rules	
  and	
  Review	  	
  Risk assessment for segment loading is an optional exercise, applicable to sensitive processesor those projects, which may require detailed design documentation. Present industry
experience has shown that segment availability is of less concern than in the past.
If needed, develop a Risk Assessment Procedure (guidelines are provided in Section 7 andAppendix 4). The basis for the Risk Assessment should include at least: FOUNDATION fieldbus final control element Risk Assessment Philosophy
 FOUNDATION fieldbus Final Control Element Process Effect Ranking Matrix
 Single failure of final control element
 Normal failure mode of final control element
 Number of devices per segment
 Diversity and redundancy
 End-user expectations and the perceptions of risk (how will a segment reallyreact?)
 Balance between availability and reliability

2.4.3	
  Segment	
  Loading	
  Rules	
  and	
  Review	  Establish the segment loading rules in the Implementation Basis and periodically review theirapplication across the project. See Section 7.0 for Segment Design Guidelines.	
  	
  2.4.4	
  Methods	
  (Templates)	
  







Do they work with the Devices and Host selected?
How easy or difficult are they to configure (drag and drop vs. keyboard entry)?
Are there any “quirks” or special considerations?
Review all options and defaults for selected Devices
What are the unknowns before commissioning and startup?

2.5	
  Implementation	
  2.5.1	  Training	
  Plan for and provide training for all necessary personnel at this stage of the project.
 Construction
 Commissioning/Start-up
 Owner/End-user
2.5.2	
  Host	  System	  Performance	
  Evaluate the Host systems to determine such things as:
 Are execution times as published?
 Does the Host slow down or have any other adverse effects due to loading?
 If planned software revisions contain significant changes, is there a plan for
implementation?
 Are the DD files for any new device revisions required available?
 How useful are the system diagnostics?
 Any unanticipated problems?

	
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  2.5.3	
  Diagnostics	
  Training	
  Plan for and provide training for all necessary personnel at this stage of the project.
• What is displayed and what does it mean?
• What needs to be done if…….?
• How can we do…....?
2.5.4	
  Maintenance	
  Methods	  Plan for and provide training for all necessary personnel at this stage of the project.
 What are the tools and equipment required?
 How is a Device disconnected and reconnected correctly?
 What is the procedure for replacing a Device when the new Device has adifferent revision level?
 What happens in a download?
 How to use remote diagnostics?
 What is a valve signature and what does it mean?
 How to plan for additional segments after plant startup.
2.5.5	
  Operations	  –	  How	  to	
  Optimize	
  the	
  Use	  of	
  FOUNDATION	
  Fieldbus	  Plan for and provide training for all necessary personnel at this stage of the project.
 What parameters are available?	
  	   What do they mean?
 How can combinations of parameter values be used to indicate how the process
is behaving?
 How to best use advanced diagnostic tools now available?
 How can valve diagnostics be used to verify or enhance performance?
 Development and use of diagnostic reports
 Who are the identified personnel to implement?
2.5.6	
  Review	
  Installation	  As the project progresses to the field, periodically audit the installations to determine if proper
installation procedures are being followed.
 Cable routing
 Correct termination methods
 Termination of shields
 Bending radius of cable Grounding Are all Devices supplied with the expected DD?
 Location of device couplers or isolated device couplers
2.5.7	
  Review	
  Field	
  Changes	  When changes are made after the initial design, ensure that the following criteria are met:
 Was a Risk Assessment Review done (if required)?
 Were segment design guidelines followed?
 Were installation practices adhered to?
 What effect will downloading the new Device have on the existing segment?
 When is the appropriate time to implement the change (can operations beaffected)?
	
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2.6	
  Summary	  FOUNDATION fieldbus projects require an extra effort to ensure “certainty of outcome.” Owners/endusers, contractors and suppliers must be willing to provide that effort. Traditional design methods
and execution are not enough. Thinking “outside the box” is required to ensure success—but users
must stick to the rules once set.
Early identification and implementation of “extra effort” items will pay off in the long run. Carefulconsideration of the addition of “bells and whistles” will avoid situations where “now we have them,
what are we going to do with them?” Attention to details and standard installations can avoid costs
and late design changes (additional costs and possible schedule delays).

	
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3.0	
  FOUNDATION	
  FIELDBUS	
  HOST	
  SYSTEM	
  REQUIREMENTS	
  
	
  

	
  

The selection of the Host (DCS) is essential for a successful FOUNDATION fieldbus technology
implementation. The various Hosts reflect different levels of FOUNDATION fieldbus
development. The Host system should be able to support EDDL, as well as FDT/DTM
technology.
Commentary:
Adequate security measures are required with these tools to ensure that the Host system anddevice database match. The user should apply these tools with caution.

3.1	
  Use	  of	
  Standard	
  Products	
  The system shall be composed of manufacturer’s standard hardware, systems software, andfirmware that can be configured to meet the stated requirements. The vendor's standard
system operating software shall not be modified to meet any of the end-user's requirements.

	
  

	
  

	
  

Specifications for inquiries and purchase orders for Host systems shall require a Fieldbus
Foundation “checkmark” indicating the proposed Host, at a minimum, has passed the HIST
registration test. Distinctive “optional” features, such as multi-bit alert support, should behighlighted in light of the end-user’s strategy for maximizing the value of the installed system.
Application software shall be designed in a manner that requires no modification to the system
operating software. Software design shall be such that future revisions or updates of thesystem operating software will not affect the successful operation of the system.
The DCS FOUNDATION fieldbus H1 network topology and settings shall comply with therecommended FOUNDATION fieldbus practices to enable communication with all targetedfieldbus devices.
While it can be done at the Host or in the field, Function Block instantiation is recommended tobe accomplished in the device manufacturer’s facility, in order to avoid extra field work or
potential errors.

3.2	
  Spare	
  Capacity	
  and	  Expansion	
  

	
  

	
  
	
  

The DCS shall be supplied with minimum 20% hardware spare capacity at mechanicalcompletion for all elements of the system configuration, including application software,graphics, history, reports, and trends. In addition, the system shall have sufficient spareperformance (e.g., communication idle time) to execute all required communication including
diagnostic information.
Communication networks within the Host should include 20% spare H1 interfaces (ports) atmechanical completion for future system expansion. Each FOUNDATION fieldbus H1 segment
shall be capable of supporting at least 12 FOUNDATION fieldbus physical devices	
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With a spare capacity of 20%, this implies the actual segment loading shall be no more than 10
physical devices per segment with two spares at the start of the project.
Power supplies for FOUNDATION fieldbus segments shall be sized to support all future
requirements including the 20% spare. In addition, there shall be sufficient room in field
junction boxes to support the 20% spare requirement.
The redundant fieldbus power supplies shall be sized taking into account the following
considerations:• In case of failure of one power supply unit, the backup unit shall be able to takethe full load.
•

	
  

	
  

The power supply spare capacity shall account for the recommendations
above, including all of the spares requirements under (7.3.1).

Commentary:
The base system is defined as the quantity of hardware and software needed to meet the
project requirements.
The level of spare capacity is a sensitive issue. Recommendations on spares range from theminimum 20% given above to 50% capacity for backplanes and marshalling terminals as this isa relatively small investment upfront, but significant to add financially and from a logistics pointof view for installation as expansion modules. Others recommend a minimum of 20-25% sparecapacity for all elements of the system configuration, including I/O cards, application software,graphics, history, reports, and trends.

3.3	
  Redundancy	
  

	
  

If redundancy is used for availability reasons, the following redundant components
should be used:• Redundant power feeds shall be provided to the bulk power supplies. The
redundant power feeds shall be independent (e.g., one power feed from PowerBus A and the second power feed from Power Bus B). At least one of thesepower feeds shall be from a UPS unless the DCS power system has battery
backup.
•

•
	
  
	
  

•
Revision 3.2.1

Redundant bulk power supplies shall feed the FOUNDATION fieldbus power
supplies. Each bulk power supply shall able to supply full load (including sparecapacity) and shall annunciate loss of AC power and low battery voltage via
separate discrete contacts. Where the bulk power supplies are comprised ofmultiple power modules, it shall be possible to remove and insert a power
module under power. Each module shall annunciate trouble or error conditions
via separate discrete contacts. In all cases, the discrete contacts shall be capableof supporting contact sense or voltage sense wiring and shall be energized withclosed contact output when indicating an error-free condition.	
  	
  
	
  
Redundant system controller power supplies with each controller power supply
fed from an independent power source.
Redundant system controllers.
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•

Redundant FOUNDATION fieldbus H1 interfaces. It shall be possible to replaceeither H1 card under power with no impact on the H1 segments associated withthe redundant cards. It shall be possible to upgrade H1 card software/firmware
without impacting communications on the related H1 segments.

•

Redundant FOUNDATION fieldbus power supplies. It shall be possible to replaceeither FOUNDATION fieldbus power supply with no impact on the H1 segment(s)associated with the power supplies.

For more details on power supply redundancy, see Section 6.2.
For more details on field device redundancy, see Section 7.5.7.
Commentary
Redundancy is also useful for on-line repair and upgrade of devices.
For applications where a failed segment (all instruments and valves on the segment go to theirfail or shelf state and remain there for up to several minutes after segment power is restored)
has very minor consequences (near zero lost production, near zero incremental safetyconcerns, etc.) it is acceptable to forego the installation of redundant power supplies andredundant H1 interfaces. The design may also consider non-redundant H1 cards if theconsequences of a “loss of view” are well understood and have minimal impact on the process
availability and safety.

3.4	
  Architecture	
  of	
  Engineering	
  and	
  Maintenance	  Workstations	
  

	
  

	
  

	
  

	
  

It shall be possible to install more than one engineering workstation in a system. Only one
engineering workstation shall be necessary to perform all control and FOUNDATION fieldbus
configuration, database generation, and editing. However, it shall also be possible to use
multiple engineering workstations simultaneously for configuration, database generation andediting.
The automation system shall use a single, global configuration database to be shared by allcomponents of the system. User shall not be required to enter the same data or configuration
more than once.
The maintenance workstation for diagnostic data handling should reside next to or be
integrated with the engineering workstation, as FOUNDATION fieldbus maintenance requires
simultaneous access to both platforms.
Commentary:
An integrated asset management package is required to gain the full benefits of FOUNDATION
fieldbus during commissioning and lifecycle activities. Additional software (“snap-ons,” etc.)	
  may
be required to utilize the data available in field devices. The location of these software packages
may depend on the Host system used.

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3.5	
  Interoperability	
  3.5.1	
  Host	  Profile	  Registration	
  Process	
  Under the new Host Profile Registration Process, the Fieldbus Foundation conducts functional
testing with a test device and specialized test Device Descriptions (DDs) and Capabilities Files(CFs). Registered devices from different vendors are also used during testing. The Host profile
under test must support a clear set of required features. A Host will conform to some, or
perhaps all, features as defined by the Host feature checklist. However, because Hosts canhave various definitions, not all features may be applicable to a Host implementation.
Therefore, it is not expected that every Host should support each feature.
Each feature contains a set of test procedures that are to be run against the Host or thefieldbus system using the Host. In order for a Host to claim conformance to the feature, it must
be able to pass the test procedures defined by the feature. The features themselves are
generic; therefore, manufactures will derive test cases, or actual implementation steps
necessary to meet the requirements of the test procedure. Fieldbus Hosts successfullycompleting the test requirements are authorized to bear the official FOUNDATION productregistration symbol.
Host Profiles and Classes
A Host Profile defines a minimum set of FOUNDATION-specific features that must be
implemented by a Host to achieve compliance to a specific Host class. A Host may
incorporate one or more hardware and software components as defined by the Host
manufacturer. Currently, the Fieldbus Foundation defines four profile classes. These include:• Class 61 – Integrated Host: Primary, on-process Host that manages thecommunication and application configuration of all devices on a network.
• Class 62 – Visitor Host: Temporary, on-process Host with limited access to device
parameterization.
• Class 63 – Bench Host: Primary, off-process Host for configuration and setup of a noncommissioned device.
• Class 64 – Bench Host: Primary, off-process Host with limited access to device
parameterization of an off-line, commissioned device.
• Class 71 - SIF Integrated Host: Primary on-process Host for Safety Instrumented
Functions.
Each of these host classes has its own set of characteristics, primary end users, and use
cases. For the Integrated Host, primary characteristics are what you would normally associatewith a DCS Host.
Mandatory versus Optional and Prohibited Features
Host testing and registration includes various levels of features for different Hosts. Dependingon the type of Host, these features can be mandatory, optional, or even prohibited. For eachprofile, individual features are marked according to a requirement.
• Mandatory features for a particular Host must be implemented in order to achievecompliance for the relevant profile.
• Optional features may or may not be implemented. If implemented, the optional	
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•

features will be tested and credited as part of compliance for the relevant profile.
Prohibited features are restricted in that profile in order to minimize the possibility of
incurring unintended operations (such as changing critical configuration parametersthat have been set up by another Host). A candidate cannot achieve compliance to a
HIST profile if any prohibited features is available in that profile.

Staged Implementation: from A to B and Beyond
When you look at host profile testing information for different classes, you will probably notice
an “a” or a “b” designation. For example, a Host could be registered to a “Profile 61a” or“Profile 61b”. These alphabetical designations indicate different versions of host testing andregistration. The “a” profiles represent the first wave of Host Profile testing that occurred after
the original Host Interoperability Support Test. The “b” specifications represent a step forward
for Host testing. In this new specification, more features are mandatory. The following Hostfeatures have gone from "optional" to "mandatory" with the new host profile 61b:
• Block Instantiation – Allows full utilization of fieldbus devices supporting instantiable
function blocks. Primarily intended for control in the field (CIF).
• Multiple Capability Levels – For devices where certain blocks/features are optional(licensed), the standard or higher capability level can be set in the tag placeholder
during system configuration to prevent unsupported blocks from being used in thecontrol strategy. This prevents surprises during commissioning. It also makes device
replacement easier.
• Enhanced Function Blocks – Allows full utilization of enhanced blocks (standard blocks
with additional parameters).
• Profiled Custom Function Blocks – Allows full utilization of non-standard blocks.
• Configuration of Scheduled Control Function Blocks – Allows developers to build CIF
control strategies.
• DD V5.1 Device-Level Access (enhanced Electronic Device Description Language withcross-block) – Makes fieldbus devices easier to use by enabling a dashboard with all
diagnostics on the same page, and all setup on one page, regardless of which block it
is in.
Beginning in 2010, all Hosts tested had to be tested under the “b” profiles. Hosts tested underthe “a” profiles will be able to remain in the catalog of tested and registered Hosts, but there
will be no further testing under the “a” profiles. When selecting a registered Host, take note of
the class it was registered to in order to ensure you are purchasing the implementation you
are looking for.

3.7	  Additional	
  Capabilities	
  New capabilities of FOUNDATION fieldbus Hosts will be added to the list in Appendix 1, as they
become available.

3.8	
  Support	
  for	
  FOUNDATION	
  Fieldbus	
  Functionality	
  3.8.1	
  Host	  System	  Fieldbus	
  Functionality	  The Host system functionality should be designed to integrate the features of FOUNDATION
fieldbus as follows:• Automatic node addressing	  Revision 3.2.1- 47 -

September 2012	  • Interoperability• Direct configuration of devices• Direct integration of FOUNDATION fieldbus device operating, maintenance anddiagnostic data.
• Tuning parameters, modes, alarms and quality of data.
• Field devices shall be configurable while the Host system is operating without
shutting down the network.
• The Host system shall enable new field devices to be added to an existing
network/segment (i.e., Device Tag/Placeholder) and fully configured withoutcommissioning and start-up delays.
• The Host system should enable field device firmware to be updated without
shutting down or impacting the publish/subscribe cycle of that H1 segment.
• Only registered FOUNDATION fieldbus DD and CFF files that have been tested andapproved by the Host and device supplier should be used.
• The Host shall have a library of standard DD and CFF files or dedicated vendor
files pre-installed.	
  	
  3.8.2	
  Data	  Transfer	
  Capabilities	
  A master database in the Host will hold most of the FOUNDATION fieldbus device parameters.
External configuration tools (visitor Hosts such as handheld communicators or laptops) thatbypass this master database shall not be used for configuration. FOUNDATION fieldbus devices
enable diagnostic information. Integrated asset management packages should be employed tohandle this diagnostic information. Procedures are necessary to ensure that the masterdatabase is up to date after a configuration change.

3.9	
  Configuration	
  Tool	  	  A FOUNDATION fieldbus Host should have a configuration tool capable of online and off-line
configuration.
The configuration tool should have multi-user and multi-instance capability.

3.9.1	  Integration	  All Host FOUNDATION fieldbus functions, including engineering, configuration, maintenance,and operational display functions, should be integrated into a single, seamless Host system.
Engineering, configuration, maintenance and operational features should apply consistently
and seamlessly to conventional analog or discrete I/O, smart HART and proprietary I/O, busbased I/O, and FOUNDATION fieldbus systems. Separate software tools, displays, orprocedures specific for FOUNDATION fieldbus and different from conventional are notdesirable.
3.9.2	
  Features	
  

	
  

	
  

FOUNDATION fieldbus Host configuration should be consistent in method and “look and feel” withconventional configuration.
Internal mirror or shadow function blocks used by control systems to map FOUNDATION fieldbus
Function Blocks to internal proprietary Function Blocks should be completely transparent to theconfiguration engineer, maintenance technician, and operator. It is essential that the shadow
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block maintains data integrity, freshness and quality.
The FOUNDATION fieldbus Host configuration tool should seamlessly and transparently
integrate with, and maintain the master configuration database. Saves, restores and partial
downloads of the master control system database should be seamlessly and transparently
accomplished for both FOUNDATION fieldbus and conventional control strategies by the same
configuration tool.

3.9.3	  Capabilities	
  The Host should be capable of offline configuration, simulation and testing of all FOUNDATION
fieldbus Function Blocks and parameters, support of DD Services and Common File Format(CFF) specifications, as well as:
•

•
•
•
•

Soft simulating and testing any and all FOUNDATION fieldbus control strategies.	
  	
  Importing non-native, bulk configuration data for developing configuration of larger
project databases.
Simple or complex online FOUNDATION fieldbus control strategy creation or
modification.
Transparently managing the macrocycle schedule in order to maintainminimum unscheduled acyclic time.
Providing alerts and messages for FOUNDATION fieldbus configuration errors.

3.9.4	
  Required	
  Function	
  Blocks	
  

	
  

	
  

The Host system shall support configuration and/or implementation of the following
FOUNDATION fieldbus function blocks in field devices:
I/O Function Blocks:
Implementation

Function• Analog Input Function Block (AI)Required• Analog Output Function Block (AO)

Required• Discrete Input Function Block (DI)

Required• Discrete Output Function Block (DO)Required• Multiple Analog Input Function Block (MAI)

Required• Multiple Analog Output Block (MAO)

Optional• Multiple Discrete Input Function Block (MDI)

Optional• Multiple Discrete Output Function Block (MDO)

Optional

	
  

	
  

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Analog Control Function Blocks:
Function• Proportional Integral Derivative Function Block(PID)

Implementation
Required• Input Selector Function Block (IS)Optional• Control Selector Function Block (CS)

Optional• Arithmetic Function Block (AR)Optional• Signal Characterizer Function Block (SC)

Optional• Integrator Function Block (IT)Optional

	
  
	
  

SIF Function Blocks (for Class 71 Host only):	  	
  Function• SIF Analog Input Function Block (SIF-AI)• SIF Discrete Output Function Block (SIF-DO)

Implementation
Required
Required	
  Commentary:
Logical blocks should be used with caution in field devices at this time, as they are not yet
uniformly applied by all manufacturers.

3.10	
  Troubleshooting,	
  Maintenance	
  and	
  Diagnostics	
  The Host should be capable of commissioning, setup, and maintaining all FOUNDATION fieldbus
devices. This function should be integrated into the Host and available from Host workstations.
The following functions should be supported:• Report of load on all segments.
• Error counters for all segments.
• A schedule (time chart) report for H1 networks/segments.
• An online reconcile function to allow change management when replacing fielddevices.
• Ability to enable/disable, prioritize, report, alarm, and acknowledge all device
alarms.
• Add a new FOUNDATION fieldbus device to a network/segment. Add a future
FOUNDATION fieldbus device to a network/segment through use of placeholder
templates.
• Methods for managing FOUNDATION fieldbus device states from/between offline,
spare, standby (where applicable), commissioned, and mismatch states and	
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•
•
•
•
•
•
•

manage all address changes transparently.
Manual address changes or use of third-party configuration tools shall not be
required.
Simple and complex commissioning functions, including transmitter rangechanges, zeroing, and control valve positioner setup (methods).
Support for DD methods and menus (wizards) for all maintenance functions
to walk technicians through the necessary maintenance procedures.
Provide specific maintenance displays, organized in a logical manner, for all
FOUNDATION fieldbus devices using specified language descriptors and definitions
with access to all parameters.
Ability to mirror existing FOUNDATION fieldbus device configuration (all FBs andparameters) onto a new FOUNDATION fieldbus device to allow quick device
replacements.
Display of commissioning and maintenance screens shall be possible from theoperator/engineering workstation.
Easily determine mismatches between the configuration in the field device
and the configuration database.

3.11	
  Advanced	
  Diagnostics	
  and	  Computer-­based	
  Maintenance	  3.11.1	
  Asset	  Management	
  Systems	
  

	
  

	
  

	
  

An integrated instrument health-monitoring (asset management) package will be required togain full benefits of FOUNDATION fieldbus during commissioning and lifecycle activities. The
necessary hardware and software should be an integral part of a Class 61 Host. The design
should also include sufficient numbers and types of equipment to support the simultaneoustasks of operations, engineering and maintenance. Supplemental (temporary) hardware may
be necessary during commissioning activities.
Security of the integrated Host system needs to be protected through methods such as
role-based access, ensuring control of data integrity while allowing access from all required
locations or systems.
Successful inclusion and implementation of asset management also requires early
development of work processes to utilize the diagnostic tools as event triggers throughtechniques such as diagnostic alarm prioritization.
Commentary:
One primary benefit of installing a FOUNDATION fieldbus network is to get more “real time”
information about the process and the device itself. The intelligent device can make available
to the operator, technician, inspector and engineer or plant manager hundreds of different
parameters about the process or instrument from a single smart device.

3.11.2	
  Minimum	
  Diagnostic	
  Requirements	  At a minimum, diagnostic capabilities shall report critical failures of devices. Diagnostics shallbe reported to the Host via FOUNDATION fieldbus alarms and alerts. Polling schemes fordiagnostics are not acceptable. Diagnostics should be reflected in data quality supplied to the	
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human interface and all applications or data users, as well as through separate diagnostic
alarms intended for maintenance.
To make optimal use of device intelligence, it is highly recommended to specify devices that
support role-based diagnostics as delineated in FF-912, based on the NAMUR NE107
standard. Certain optional Host features are needed to make full use of the alerts generated bythese field devices, such as Process Alert Management Configuration and following the HIST
test for a Class 61 Integrated Host.

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4.0	
  SOFTWARE	  CONFIGURATION	  GUIDELINES	
  4.1	
  Control	
  System	
  Graphics	
  

	
  

All modifications to, or reconstruction of, control system graphics shall comply with existing end
user standards for Host system graphics detailing line colors, icon details, trend pages, alarm
tracking, and historical data. While operator interface graphics need not differ substantially fromconventional projects, users may wish to consider additional information (for example, signal
status, actual mode not equal target mode) that will be meaningful to the operator. For device
diagnostics and alert annunciation, dedicated FOUNDATION fieldbus faceplates shall be applied.
Like process alarm management, no device alarms shall be presented to the operator which
are redundant and do not motivate some specific operator action.
Commentary:
FOUNDATION fieldbus provides an abundance of additional information to the DCS systemuser. A dedicated asset management system should be employed for the diagnostic data.
Otherwise, the panel operator will have to acknowledge all device status alarms and inactivatethem from the operating console. Where an asset management system is not installed, theFOUNDATION fieldbus faceplates shall be installed which partially enable such activity.

4.2	
  FOUNDATION	
  Fieldbus	
  Device	  Segment	
  Addressing	
  
	
  

	
  

	
  

	
  
	
  

	
  

Each fieldbus device shall have a unique physical device tag and corresponding segment
address.
Commentary:
A device tag is assigned to the device when it is commissioned and (for most device states)
retains the tag in its memory when it is disconnected. The network address is the current
address that the fieldbus is using for the device.
The Fieldbus Foundation uses node addresses in the range 0-255. Each vendor allocates thenode numbers in a way that is somewhat unique. Host Suppliers all have reserved low
numbers for overhead and DCS interfaces, and a group above that for live field devices, andsome higher numbers for spares.
Addresses used by FOUNDATION fieldbus are in accordance with the following ranges:
o 1–15 are reserved.
o 16–247 are available for permanent devices. Some DCSs may further
subdivide this range. This range is typically shortened for efficiency.
o 248–251 are available for devices with no permanent address such as new
devices or decommissioned devices.
o 252–255 are available for temporary devices, such as handhelds.
Third-party systems or configuration tools connected through a communications interface to an
H1 network shall NOT be used to:	  	
  • Interrupt the operation of any device within the system.
• Change device addresses (handheld devices shall not be used to set the device tag

	
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and address due to database inconsistency issues).
• Affect the link schedule.
Third-party tools shall only use acyclic (client/server) communications. Communicationinterfaces shall have user-administered security to control read/write access and to selectallowed functionality.
Commentary:Default settings in some configuration tools can disrupt link operation without any overt action
by the operator of the tool.
The field device management implementation shall be capable of completely configuring
parameters associated with FOUNDATION fieldbus devices.
A FOUNDATION fieldbus H1 interface in the DCS always has the primary LAS functionality. A
redundant H1 interface (if installed) will take over the LAS function as Backup Link Active
Scheduler (BLAS) in case of failure of the first interface. In addition, a field device may have
BLAS functionality.
User experience has been that the real demand for a device-based Backup LAS is rare, inparticular where redundant H1 interfaces have been specified (see Section 3.3). Since the
BLAS functionality can add significantly to download times, users are advised to implement
BLAS judiciously, only where no redundant H1 card exists, and only where specific loops are
judged to require “zero” interruption of PID execution. An example might be a level loop on avessel with very low residence time, where the default “hold last position” behavior would resultin an undesirable process state.
The field device with backup LAS enabled shall have the lowest commissioned FOUNDATION
fieldbus device address.

4.3	
  Control	
  Functionality	
  Location	
  

	
  

	
  

Within FOUNDATION fieldbus devices, control is contained in software entities called modules.
The control blocks can be a mix of both FOUNDATION fieldbus and other blocks. The fieldbus
control blocks can be assigned to run in a field device or in the DCS controller.
Control in the Field (CIF) is preferred when possible. Unless otherwise specified in project
documentation, CIF optimizes communication as less H1 communication is required andcontrol loops show lower variability due to better synchronization. CIF shall be used for simple
single loop and cascade PID control within the same H1 segment. The PID function block shallbe located in the final control element for single loop. The system shall be configured to allow
the operator to manipulate the valve manually and provide alarm of the condition when atransmitter is completely inoperative due to local failure (such as power loss, communication
loss, or complete electronics failure).
Commentary:
Transmitter and control valve positioners typically have a PID function block available, whichraises the issue of where the PID function should be located. Issues such as H1 segment

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communications overhead, execution speed, advanced diagnostics, failure mode, and operator
access are generally considered when choosing where the PID block resides. However, thegeneral consensus is that the PID block should be located in the control valve positioner. As
with conventional control systems, loop and device failure modes need to be determined andthe proper course of fail action identified for each control loop.
If all function blocks of a single PID control loop cannot reside on the same segment, the PID
control algorithm shall be placed in the DCS controller. Cascade PID control can be
implemented in the field if all function blocks for both inner and outer loops reside on the same
segment. Complex control shall be fully implemented in the controller.
Commentary:
This restriction may not apply for systems supporting bridge capability between FOUNDATION
fieldbus H1 networks. Note that bridging may be possible with the use of HSE, but not all Host
systems with HSE support bridging. Note that there is limited user experience at this writing
and, therefore, the user should thoroughly test any implementation using bridging.
Each FOUNDATION fieldbus control strategy or module will be named as shown on the P&ID.
The primary loop function block used for operator interface (AI or PID) will share the module
name. With some systems, using consistent tagging conventions between devices and theirassociated loop can facilitate improved access to device information.

4.3.1	  Recommendations	
  for	  Display	
  and	
  Alarm	
  of	
  Loop	  Variables	
  for	
  Control	
  in	
  the	
  Field:	
  	
  Users will note that the measured/controlled value of any FOUNDATION fieldbus PID loop canpotentially be accessed from a number of devices. When the PID resides in the final element(valve positioner), the HMI can be configured to access all the loop variables from there.
However, a fault in that device will mean the measured value and alarms will cease updatingon the operator interface. In such cases, it is better if the host accesses the PV and alarms
from the transmitter (measuring device) directly wherever possible.
Commentary:Users should also recognize that addressing “PV,” whether from the PID block itself or directlyfrom the AI (analog input FB), makes its update part of the “asynchronous” or non-deterministic
portion of loop communications (macrocycle), so display and trending latency may be
increased. The same is true when accessing “read back” (typically actual valve position as
seen by the positioner) from the loop’s AO block. Some vendors map the “read back” to the AO
block’s BKCAL_OUT parameter (“Use PV for BKCAL_OUT” checkbox) which then makes it
update with the deterministic portion of the macrocycle.

4.4	
  Segment	  Scheduling	  The cyclic communication (publish/subscribe) shall only be used for control applications
including process indication points. Updating of graphics, faceplates, etc. as well as
configuration and diagnostic information for maintenance shall be implemented acyclically(client/server). A minimum of 30% of macro cycle time should be allowed for unscheduledacyclic communication.
Acyclic communication is classified into two types namely, scheduled, such as updating
graphics, faceplate and unscheduled, such as configuration download and operator action. Sum	
   Revision 3.2.1- 55 -

September 2012	  of the cyclic communication and the scheduled acyclic communication should be counted as thescheduled time.

	
  Commentary:
This represents the minimum acyclic time on a network. It is recommended that for a new
installation, a minimum of 50% unscheduled acyclic time be available to allow for system
expansion, addition of new devices, or modification to the configuration in the future.
Commentary:
Some Hosts (DCSs), by default, apply cyclic communication to update graphics. The correctcommunication type shall be selected during the control design and implementation phase.

4.5	
  Configuration	  Options	  and	
  Defaults	
  4.5.1	
  Control	
  Narrative	  A control philosophy guideline document shall be created for all FOUNDATION fieldbus projects.
The guideline shall define all typical control strategies, with control modules, Function Blocks
and all parameter configurations defined. This guideline shall set Function Block and control
module philosophy for this and future FOUNDATION fieldbus projects at the facility. The
configuration guideline shall be reviewed and approved by the end-user engineering
representative.
4.5.2	
  Configurable	  Options	
  

	
  

Standard FOUNDATION fieldbus blocks have configurable options (e.g., Status_opts,
Control_opts) for handling signal status, mode shedding, set point tracking, etc. As part of theguideline, or as separate standard “configuration templates,” the control narrative/guidance
document should recommend default settings for relevant parameters and considerations for
deviations from the recommended defaults. Some of the parameters to be addressed should
include, but are not limited to:
Parameter
Permitted Modes

Resource
Block
X

Transducer
BlockX

Shedding Options
Features - Reports

Function
Block
X
X

X

PV Status

X

Fault StateX

Fault State Time
I/O Options

X
X

Device SpecificParameters

X

X

X

	
  

	
  
	
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5.0	
  FIELD	
  DEVICE	  REQUIREMENTS	
  5.1	
  Fieldbus	
  Registration	
  

	
  

All devices must, as a minimum, satisfy the requirements of the Fieldbus Foundation’s
registration laboratory. In the case of the foundation, this is the FOUNDATION fieldbus “checkmark” registration logo and listing on the approved devices list maintained at www.fieldbus.org.
The ITK (Interoperability Test Kit) is used in this registration process to check the basic
FOUNDATION fieldbus functionality. This verifies interoperability of devices as indicated in thefollowing example:

	
  
	
  

Example 5.1 FOUNDATION Fieldbus Registration “Check Mark” Logo.
Commentary:
The end-user should verify with the Host vendor that their system is compatible with allversions of a device (current ITK version and all prior versions from 4.1 on).

5.2	  Support	
  for	
  FOUNDATION	
  Fieldbus	
  Functionality	
  

	
  

	
  

All FOUNDATION fieldbus instruments should support Methods to allow automation of online
procedures (such as calibration) from the Host. Most FOUNDATION devices have Methods toallow automation of online procedures (such as configuration) from the Host system.
Commentary:
Methods are preferred for simple procedures. FDT/DTMs may be preferable for more complex
procedures using graphical user interfaces and data retention storage, such as radar level andvalve sequencing.

5.3	
  Fieldbus	
  Function	
  Blocks	
  	
  The following Function Blocks are defined by the Fieldbus Foundation. Not all of these
Function Blocks are available for use in all field devices, and some are not available and/or do
not yet have interoperability tests.
Standard Function Blocks:	  	
  As defined by FF-891: Function Blocks – Part 2. The ten standard Function Blocks are as
follows:

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•
•
•
•
•

	
  

	
  

	
  

	
  

	
  

•
•
•

AI - Analog Input
AO - Analog Output
B - Bias
CS - Control Selector
DI - Discrete Input
DO - Discrete Output
ML - Manual Loader
PD - Proportional/Derivative Control
PID - Proportional/Integral/Derivative Control
RA - Ratio

Advanced Function Blocks:
Advanced Function Blocks defined in FF-892: Function Blocks – Part 3 are as follows:• Device Control• Set Point Ramp
• Splitter• Input Selector• Signal Characterizer• Dead Time• Calculate• Lead/Lag• Arithmetic• Integrator• Timer• Analog Alarm
Additional Function Blocks:
Function Blocks are defined in FF-893: Function Blocks – Part 4 as follows:• Multiple Analog Input• Multiple Analog Output• Multiple Discrete Input• Multiple Discrete Output
Flexible Function Blocks (FFBs) are defined in FF-894: Applications as follows:• Flexible Function Block (IEC 1131 Logic)
SIF Function Blocks are defined in FF-895: Safety Instrumented Functions (SIF) Function
Blocks as follows:•	
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•

SIF Digital Output

Commentary:
It can be seen from this list that not all Function Block types are suitable or available for all
instruments. It is, therefore, essential to make a considered choice when specifying the
Function Blocks to be included in various field device types. Although it is appropriate to host
most of these blocks in controllers, their use in field devices on H1 networks/segments may belimited (due to the availability of devices), to the following blocks: AI for transmitters, AO and
PID for valves, and DI/DO for discrete devices. See Sections 4.3 and 4.5 for further guidanceon use of field device Function Blocks. Additional Function Blocks are likely to be added in the
future, therefore, it is wise to check Function Block availability with the instrument
manufacturer and ensure that the Host system will allow the use of the desired Function
Blocks at the time of purchase, thus ensuring that the features desired are available for use. It
should be noted that there is seldom a need to have all Function Blocks available in all fielddevices. The user should also verify that functionality in the Host and field device iscompatible, should it be necessary to revise the functionality location.

5.4	
  User	  Application	
  Blocks	
  	  Function Blocks handle the control strategy. The Function Block diagram is a graphicalprogramming language for building control strategies.
There are two kinds of blocks found in FOUNDATION fieldbus devices, device application blocks
and configuration blocks.
Configuration blocks are used to configure devices. These are:
To configure the device:	  • Resource Block• Transducer Block holding the device diagnostic data
To configure the application:• Function Blocks whose schedule and usage is completely user-configurable

5.4.1	
  Resource	
  Block	  The Resource Block (RB) describes characteristics of the FOUNDATION device, such as thedevice name, manufacturer, and serial number. The following should be considered for design
purposes:• The user cannot make modifications• The user can change parameters• There is only one RB in a device.
	  • The RB is the only obligatory block in FOUNDATION devices• The RB contains ID and general information related to the whole resource or state of theresource (no real details about device functionality)	
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September 2012	  • The RB contains overall health and operational status, includes write protection, andenables simulation, etc. Newer devices (ITK 6.x and above) may have device diagnostic
alarm capability.
5.4.2	  Transducer	
  Blocks	
  

	
  

	
  

	
  

	
  

The Transducer Block (TB) contains information such as calibration date and sensor type.
Field Devices require at least one Transducer Block to make the device useful.
TBs decouple FBs from the local Input/Output (I/O) functions required to read sensors andcommand output hardware (i.e., this is where parameterization, calibration and diagnostics forthe device are carried out).
Some devices have several TBs where dedicated TBs are used for diagnostics, multiple
measurements, or to manage a device’s local display. Diagnostic coverage is all defined in the
TBs of the device. Interoperability of all TB parameters with the Host system is essential for
asset management.	
  	
  The device vendor shall mark the diagnostic TB parameter as such in the DD (Device
Description Files) for ease of access. Furthermore, a clear Help File shall be added to eachparameter clarifying the device vendor’s knowledge on how to use the parameter information.
The Fieldbus Foundation has defined several standard TBs including pressure, temperature,
valves and some others. Devices that conform to these specifications are preferred.

5.4.3	  Function	
  Blocks	
  

	
  

	
  

	
  
	
  

Function Blocks (FBs) should be employed in user-defined Function Block applications toprovide various functions required in a control system (for example, input, output, signal
selection, and other control actions). In other words, Function Blocks are the control strategy.
FBs are built into FOUNDATION devices, as needed, to achieve the desired control functionality.
Some FBs can be built into the devices and some can be instantiated (preferably at thefactory). The factory instantiation option should be used as it results in less confusion andconfiguration effort. Reference should be made to the manufacturer's device manual for
optimal configuration.
Depending on the DCS (Host) manufacturer's policy, some of the specific device parameters
may not be shown. In the case of diagnostics this may reduce the device functionality.
Reference should be made to the manufacturer's device manual for optimal configuration. Not
all available FB types may yet be included in the present ITK tick marking. However, not all
FBs are required. Some FBs are only of interest if Control in the Field (CIF) is applied. Then, it
is essential to make a considered choice when specifying the Function Blocks to be included
in various field device types.
Commentary:
It is recommended to employ commonly used Function Blocks available in both the Host and	
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field device. Use specialty Function Blocks with great care.
Although appropriate to Host system controllers, these blocks may be limited to the following:• AI for transmitters• AO and PID for valves• DI/DO for discrete devices
Additional Function Blocks are likely to be added in the future. It is, therefore, wise to check
Function Block availability with the instrument manufacturer at the time of purchase, thus
ensuring that the features desired are available for use. However, the interoperability of otherthan the essential FBs is not guaranteed with every Host system, thereby limiting the CIF
applicability.
The Fieldbus Foundation tests of Function Blocks only confirm that they are present and how
their external interface behaves, not how well they work internally. Each manufacturer canconfigure the internal operations of Function Blocks as they wish and will, in fact, do so since
this will give them a competitive advantage. It is thus worthwhile to check which manufacturer	  gives the best result in terms of macrocycle efficiency and the needs of the relevant process.
This is mainly required when CIF is applied or fast loop execution is required.	
  Example:Each manufacturer can implement the PID algorithm with unique equations while still providing
control in a PID block.

	
  

	
  

For some MOVs, it may also be advisable to check the FB execution times. The execution timeof PID blocks differs per vendor. Furthermore, each manufacturer can implement the PID
algorithm with unique equations while still providing control in a PID block. In most cases, thealgorithm has no impact on the loop performance, as at present only simple control shall beapplied with CIF. Section 5.3 provides a list of standard, advanced, and multiple I/O FBs.
Commentary:
The Fieldbus Foundation has defined dozens of standard Function Blocks. Additional Function
Blocks may be defined and implemented by each manufacturer to accommodate individual
control strategies and signal processing needs.
Each manufacturer configures the internal operations of FBs as they wish—looking forcompetitive advantage. The Fieldbus Foundation tests only confirm that FBs are present andhow their external interface behaves, not how well they work internally. It may be a good idea
to, as far as possible, only use standard blocks in the control strategy. Because enhanced
blocks (standard blocks with additional parameters) have extensions that are unique to eachmanufacturer, it becomes much more difficult to replace a device that uses enhanced blocks.
Devices with "instantiable" blocks have the advantage that they typically support both thestandard block (e.g., PID) plus enhanced blocks (e.g., enhanced PID with some additionalfeatures). This way, it becomes easy to choose standard blocks whenever sufficient, andenhanced blocks only when really required. Thus, instantiable blocks make interchangeability	
   Revision 3.2.1- 61 -

September 2012	
  much easier.

5.5	
  Control	
  and	
  Data	  Handling	  5.5.1	
  Fault	
  Handling	
  

	
  

	
  

	
  

	
  

	
  
	
  

	
  
	
  

	
  

	
  

Fault detection and processing by ITK-approved FOUNDATION fieldbus devices complies with
the FOUNDATION standards. PV status shall be available on tag basis and generated for inputs
and calculated variables. In previous ITK versions, the PV status would be set to uncertain if
the following condition was true:• If a value is out of the scaled range
Commentary:
FOUNDATION fieldbus specifications no longer support flagging an out-of-range condition as
uncertain.
The PV status shall set to bad if any of the following conditions are true:• If a value cannot be measured or calculated• If device diagnostics have identified a failure (e.g., open thermocouple)	
  	
  PV status should be propagated through control schemes and to the historian, if applicable. It
shall be possible for a PV status to be used as a logical input to initiate control algorithm
changes.
When a control algorithm's input is set to bad or uncertain, or in the event of communications
subsystem failure, it shall be possible to configure the output to fail as follows:• Configured fail state (hold last good value or shed to manual)• Mechanical fail state (loss of air position)
All final control elements shall have a configured fail-state on loss of segment communication.
Configured Fail State:
The configured fail state shall be either open, closed, hold last position or a directed
percentage open. The valve shall go to its configured fail state on loss of communication or
upon a configured event.
The configured fault-state value shall be 0% (closed) for fail closed and 100% (open) for failopen valves unless process conditions require a specific position.
A configured event may be:••

Loss of input signal to the valve PID block
Process event (emergency trip) or diagnostic event (valve fault)

Commentary:
Some positioners offer fail-to-last position, however, this is device specific and shall be	
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addressed on a case-by-case basis. Note that valve failure mode is a user’s choice and can bedifferent for a diagnostic event or communications loss. An example might include Fail Last forcommunications loss, while a diagnostic event may put the valve in a predetermined failure
position.
Mechanical Fail-state:
The Fault-state Time can be configured to a minimum of 5s (or any user-selected time). This
will hold the last value (valve position) for that time period during a communication failure, andthereby increases plant availability by providing an opportunity to reestablish communications.

5.5.2	
  Regulatory	
  Control	
  

	
  

	
  

	
  

	
  

Algorithms:
Standard FOUNDATION fieldbus software algorithms shall be available to perform regulatory
control functions. These process control functions shall be performed by using predefinedalgorithms with configurable parameters.
Control algorithms are not standardized. For example, PID algorithms in field devices havedifferent equations but all the parameter naming is the same. Also, PID algorithms in Host
systems and in field devices may have different capabilities. The user should be aware ofthese differences and exercise care if switching between control in the Host vs. control in thefield.	
  	
  Setpoint Clamps:
Upper and lower clamps shall be available on all setpoints.
Windup Protection:
Control functions that include integral action shall be provided with windup protection. Windup
protection shall inhibit the integral action when the control block output is constrained byconditions such as:• Output at high or low limits of span.
• Output at high or low clamps.
• Output is connected to the setpoint of a secondary controller, which is clamped.
• Output is not connected to any valid device or algorithm.
• Output tracking is active unless the primary controller is connected to a secondary
controller which is not in cascade mode, or if a controller loses communication with theoutput module due to hardware failure.
The windup protection status shall be clearly visible to the operator in a standard faceplate
display, so the operator is aware of this condition. The windup protection status shall set a
parameter that is accessible to graphic displays and application programs.
Control functions and computational functions shall include the ability to propagate the windupparameter through multilevel control strategies.

	
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September 2012	
  5.5.3	
  Factory	
  Configuration	
  (Basic	
  Ordering	
  Information)	
  

	
  

	
  

	
  

FOUNDATION fieldbus instruments shall be configured by the manufacturer, including atleast the following information:••

Device identification
Tag name

In addition, it may be advisable to order devices with the correct FOUNDATION fieldbus address(or at least a temporary address – see section 4.2) and with Link Master functionality (ifavailable) turned off.
Commentary:
This will enable faster commissioning. If it is decided to not apply pre-tagged and preaddressed devices, a dedicated commissioning work procedure is needed in which tag andaddress setting is performed.

5.6	
  Device	
  Diagnostics	
  The diagnostics shall be able to provide key information on the ability of the device to measure
or control the process, including but not limited to basic device failure diagnostics andadvanced diagnostics.

	
  Basic Diagnostics:	  	
  Basic diagnostics are the device fault diagnostics that affect signal status, which shall be
continuously viewable from any process control host. They help determine common problems
with the device, communication path, and host. When transmitter diagnostics change thesignal status to BAD or UNCERTAIN the default behavior is for the affected PID ACTUAL
mode to shed to MANUAL. Users are encouraged to change this default behavior so that PID
ACTUAL sheds mode only on BAD status. Select “treat UNCERTAIN as GOOD.”	  When an output (e.g., positioner) fault occurs, the affected loop PID is forced to IMAN
(initialization manual).

	
  Advanced Diagnostics:
Advanced diagnostics include full device diagnostics so that the device health can be
determined without removing it from the process. Advanced diagnostics come in two forms,
online and off-line.

	  Online:Online diagnostics perform their function while the device is performing its normal function, andprovide the capability to alert operations in real-time if a problem needs attention. This function
provides one of the primary benefits of FOUNDATION fieldbus and should be supported by all
devices as rapidly as possible.

	  Offline:Offline tests provide limited benefits and may not justify their cost.

	
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FOUNDATION fieldbus devices should be capable of supporting incremental Device Description(DD) for extra functionality and/or software revisions in device memory. Capabilities include thefollowing diagnostics and should provide key information on the impact that an output device
has on the process, including but not limited to:• Position accuracy• Operating resolution• Total valve travel• Packing friction and hysteresis• Static and sliding friction• Dead band
• Operating temperature
For valve positioners, the dedicated software package to analyze the positioner data shall befully interoperable with the Host system.
Commentary:
The selection of Host system asset management, positioner type (including diagnostic
coverage) and interoperable software package is key for enabling successful diagnostics fromFOUNDATION fieldbus positioner/valve combinations.	
  	
  

5.7	
  Field	
  Device	  Power	
  

	
  
	
  

FOUNDATION fieldbus devices may be powered either from the segment (bus), or locallypowered, depending on the device design. If at all possible, field devices should be bus
powered.
If a device requires more power than can be provided from a FOUNDATION fieldbus segment,
the 4-wire approach is to be applied (separately powered).
Commentary:
Bus-powered devices typically require 10-30 mA of current at between 9 and 32 volts. Most
devices have a current consumption at 15 to 17 mA. Devices should strive for minimum power
consumption, without negatively impacting desired functionality.

5.7.1	  Polarity	
  

	
  

FOUNDATION fieldbus device communication signal shall be polarity insensitive. No inversion of
the communication messages shall occur.
Commentary:
Some older FOUNDATION devices were polarity sensitive and, if installed incorrectly, could
cause network problems. It is, therefore, considered good practice to maintain wire polarity andcolor throughout a project.

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September 2012	
  5.7.2	
  2-­Wire	
  Field devices shall be loop-powered from the fieldbus power supply unless the device power
consumption exceeds the limits of the segment. In the latter case, 4-wire configuration shall beapplied.
5.7.3	
  4-­Wire	
  Externally powered devices (e.g., 4-wire devices) with FOUNDATION fieldbus shall haveisolation between external power and fieldbus signal.
5.7.4	
  Short-­circuit	
  Protection	
  

	
  

Devices should be compatible with the selected type of short-circuit protection. The maximum
spur current (generally the startup current of the field device) plus an allowance for at least one
piece of test equipment on the spur should not exceed the current required to activate the shortcircuit protection.
Commentary:
Earlier versions of short circuit protection and devices, which drew relatively high current, could
activate the short-circuit protection circuitry and thereby take the spur off line when test
equipment such as a handheld communicator was connected to the spur. Later revisions ofdevices and test equipment draw less current and short circuit protection devices haveincreased the threshold to activate the protection. The user should evaluate the combination ofdevices, test equipment and wiring components to ensure compatibility.	
  	
  

5.8	
  FOUNDATION	
  Fieldbus	
  Device	
  Requirements	
  for	
  Safety	
  Applications	
  
•
•

•

	
  

	
  

The device shall be registered by the Fieldbus Foundation.
FOUNDATION for SIF transmitters used to sense the process may provide additional
diagnostics that will provide more detailed information for use to decide which action totake upon detection of the fault.
It is preferable that the same physical hardware should be usable for safety and nonsafety applications. It is also preferable that the firmware and software be selectable byapplication.

Commentary:
When newly delivered, devices will reset to a default set of parameters upon initial power up. A
device that supports both the normal and FOUNDATION for SIF protocols will startup such that it
accepts both safety related and non-safety related configuration (i.e., it is ready to understandand speak both FOUNDATION fieldbus and FOUNDATION for SIF protocols.
• FOUNDATION fieldbus – Field devices shall be documented to be compliant to IEC
61508.
• FOUNDATION for SIF field devices provide additional write access security measures todevice configuration blocks required to ensure compliance to IEC 61511 and IEC
61508. The devices shall include capability for remote locking and unlocking to prevent
unauthorized access (change of FOUNDATION for SIF parameters). FOUNDATION for SIF

	
   Revision 3.2.1- 66 -

September 2012

	
  

•
•
•
•
•

	
  

field devices unlock message may be initiated by a physical key or password from anengineering workstation. When the write protection is applied, all FOUNDATION for SIF
Function Blocks within the field devices return to the safe operating mode.
FOUNDATION for SIF does not permit sub schedules.
FOUNDATION for SIF has no program invocation, action object, alerts, trends, block
instantiation or Flexible Function Blocks, and has restrictions on bridging.
When a device detects an internal failure, a failure status should be available to thelogic solver.
Once the safety-related configuration has been installed, the write-lock should be set.
FOUNDATION for SIF field devices clocks should be synchronized with the Host using
the regular FOUNDATION fieldbus clock synchronization mechanism and shall include
the capability to time-stamp events (e.g., a pressure exceeds its limit).

Commentary:	  	
  FOUNDATION for SIF field devices provide additional communications fault detection, which has

been approved by TÜV to IEC-61508, including diagnostics to reduce the potential for
undetected dangerous failures to a level acceptable for SIL 3 applications

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6.0	
  SEGMENT	  COMPONENT	  REQUIREMENTS	
  6.1	
  GENERAL	  	
  A number of additional components are required to complete a FOUNDATION fieldbus segment. Thesesegment components are discussed in detail in Sections 6.2 through 6.8, and should be reviewed by
the Host system vendor as being compatible with their system.

6.2	
  POWER	  SUPPLIES	
  6.2.1	  General	
  

	
  

	
  

Power to segments shall be provided by FOUNDATION fieldbus power supplies that are fed by bulk
power supplies. There are other options for the power supply architecture for FOUNDATION fieldbus,
each having its benefits and limitations. However, options such as using non-isolated power
conditioners are not recommended.
FOUNDATION fieldbus specifications allow segment supply voltage to range from 9 to 32 Vdc. Longer
home runs benefit from higher power supply voltage. For most applications, trunk supply voltage at
the power supply will be 24 ± 2 volts (typically, IS installations will be lower).
Any power supply can be used in combination with the fieldbus power supplies (See Section 6.2.2).
The selection and implementation of power supplies is critical if only power conditioners are applied(not recommended, see Section 6.2.4).

6.2.2	
  FOUNDATION	
  Fieldbus	
  Power	
  Supplies	
  

	
  

	
  

	
  

FOUNDATION fieldbus power supplies are specialized power supplies that provide both the segmentisolation from bulk power and the power conditioner in one unit. Power conditioning prevents thebulk power supply from shorting out the communications signal, preventing the segment fromfunctioning. Isolation prevents ground loops and interference among segments.
FOUNDATION fieldbus power supplies are typically smaller than the bulk power supplies and are
dedicated to a fixed number of segments. They shall have the appropriate approval: FF-831“FOUNDATION Specification; Fieldbus Power Supply Test Specification” and associated check mark.
FOUNDATION fieldbus power supplies should be redundant, load sharing and output current
limiting, and provide facilities for monitoring faults and failures. They shall be fed by dual DC bulk
supply sources or by a redundant feed arrangement (not on a single fuse).
FOUNDATION fieldbus power supplies shall be used instead of power conditioners between bulk power
supplies and segments.

6.2.3	
  Bulk	  Power	
  Supplies	
  Bulk power supplies convert local electrical power to direct current. Multiple DC power supplies areoften combined to meet the current demand of the load plus a safety factor. It is acceptable to usebulk supplies to power other loads in addition to FOUNDATION fieldbus power supplies.
	
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A typical design includes redundant bulk power supplies with each having independent,
redundant input supply circuits.
A bulk power supply design may have its output voltage either floating or have the negative output
connected to ground. Common practice is to ground the negative supply to control the discharge
path should a voltage spike appear on the segment wiring back to the control system.
Commentary:
Grounding refers to the bulk power supply and not the FOUNDATION fieldbus power supply.

6.2.4	
  FOUNDATION	
  Fieldbus	
  Power	  Conditioner	
  The FOUNDATION fieldbus power conditioner provides impedance matching between the fieldbus
signal and the bulk power supply. It may be active, using semiconductor components, or passive with
only inductive and resistive components. It does not provide isolation and is therefore notrecommended.

	
  
	
  

Figure 6.1: Typical Arrangement of 24 Vdc Bulk Power Supply Options to Fieldbus Power
Supply.
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Commentary:
A standard bulk power supply absorbs the communications signal as it attempts to maintain aconstant voltage level. Short circuit protection is typically not provided by power conditioners. Lack ofisolation and short circuit protection adds significant risk to field installations. Problems on one
segment may affect other segments.	
  	
  

6.3	
  FOUNDATION	
  Fieldbus	
  Terminators	
  

	
  

	
  
	
  

FOUNDATION fieldbus segments require EXACTLY two terminators, one at each end of the trunk(home run) cable. The terminator is comprised of an RC network that provides 100 Ω impedance.
The terminator allows the current-based FOUNDATION fieldbus communications signal to be viewed
as a voltage while being offset on the DC segment voltage supply.
Commentary:
1. Constructing your own terminator using a 100 Ω resistor and a 1 µF capacitor will notguarantee correct segment communications, and is therefore not recommended.
2. Most fieldbus power supplies and/or field device couplers have a built-in segment
terminator.
3. Some wiring components have switchable terminators. Care should be taken to verify thecorrect quantity of terminators on a segment.
Terminators at a field device shall not be used (due to the impact on the whole segment should thedevice need replacement	
  6.4	
  Surge	
  Protection	
  
	
  

	
  

	
  
	
  

Surge protection for FOUNDATION fieldbus devices may be required in areas where induced voltage
is an issue. This includes areas such as close wiring proximity where large inductive loads arestarted and stopped, or areas known for lightning incidence (associated with segments in tankfarms, segments containing instruments on top of high towers or remote facilities such as pumping
stations, well sites, etc.).
Surge suppression consists of a low-capacitance device installed at the device's electricalconnection. It shall normally appear as an open circuit to the spur and segment to prevent any
adverse effect on communications.
Commentary:
Segment and spur protection is described in Section 7.3.5.3.

6.5	
  FOUNDATION	
  Fieldbus	
  Repeaters	  	
  Repeaters shall not be used without prior approval by the principal. Repeater functionality to extend
the length of a fieldbus segment is not normally needed or recommended. Sometimes repeater
functionality may exist in combination with IS Isolation for use in IS power supplies or IS isolated
device couplers.

	
  

	
  

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6.6	
  FOUNDATION	
  Fieldbus	
  Field	
  Device	  Coupler	
  
	
  

	
  

	
  

	
  

A FOUNDATION fieldbus device coupler or isolated device coupler (where applicable) is located where
the trunk (home run) is connected to the various device spurs. It is typically the location of one of theterminators (associated with a segment), and the location of spur short-circuit protection.
Only registered FOUNDATION fieldbus device couplers or isolated device couplers shall be applied.
The couplers shall have built-in spur short-circuit protection (to minimize the impact of a short at one
device affecting the whole segment). Spur short-circuit protection shall have visual indication (on aspur level) when short-circuit protection is active and the spur's maximum current shall be limited byarea classification and the current available to the network.
The couplers should provide visual indication of segment power as a minimum.

6.7	
  FOUNDATION	
  Fieldbus	
  Cables	  	
  6.7.1	  General	
  FOUNDATION fieldbus cables shall be single-twisted or multi-twisted pair stranded tinned copper,
individually shielded and overall shielded, 0.8 mm2 (#18 AWG) minimum with 300 V or better
insulated, and shall have a UV-resistant, overall jacket (black provides the maximum UV protection).
See Appendix 2 for cable requirements. The individual conductors within each pair will be colorcoded; positive and negative being different colors. The pairs should be sequentially numbered.

	
  

	
  

	
  

	
  

	
  

The trunk (home run) cable shall have one spare pair. Unused pairs of the trunk cable shall beconnected together with the pair shield and grounded (for noise rejection) at the fieldbus segment
shield ground connection (refer to Figures 7-6, 7-7, 7-8 and 7-9). See Appendix 2 for Cable
Characteristics.
The impedance of the cable shall be 100 Ω ± 20 Ω maximum. For longer (greater than 500 m) runs,
1.13 mm2 (#16 AWG) gauge wire should be used (to minimize the cable voltage drop) and 100 Ω ±10 Ω specification. Although the larger cable cross-section may result in higher capacitance, theassociated signal attenuation can be kept small and shall not be more than 3 dB/km at 39 kHz (thisstandard frequency is used to specify cable characteristics and is sufficiently close to the 31.25 kHz
to be applicable).
The trunk cable shall meet the ambient temperature range for the location in addition to theminimum installation temperature. In addition, installation of the cable shall comply with the
manufacturer’s specified minimum bending radius.
The individual pair shield shall be plastic-coated aluminum tape with a metallic surface inside incontact with a tinned copper drain wire. All individual pair shields shall be electrically isolated fromeach other and from the overall shield.
The overall shield shall be plastic-coated aluminum tape, with the metallic surface in contact with a
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tinned copper drain wire and wire braid (if used).
A Factory Acceptance Test (FAT) shall be performed on all supplied FOUNDATION fieldbus cables.
Pending a positive result of the factory test, an on-site insulation integrity test (between individual
wires, individual pairs, and individual wires and shields) before installation may then be deemed
optional.
The conductor resistance, screen resistance, attenuation at 39 kHz and inductance of the cable shallcomply with FOUNDATION fieldbus standards as stated in FF-844 and IEC 61158-2. Additional careshall be taken with intrinsically safe wiring techniques to ensure compliance with all local electricalapproval requirements and site practices.

6.7.2	
  Existing	
  Wiring	  	  Existing wiring can be used in FOUNDATION fieldbus installations, but should be tested to ensure it
meets the qualifications outlined in section 6.7.1. Automated tools are available, such as the Relcom
FBT-5, to test new or existing field wiring to determine its suitability for use in a FOUNDATION fieldbus
network.

6.7.3	  Spur	  Cables	  	
  The spur cables shall meet the FOUNDATION fieldbus specification as discussed in Section
6.7.1.
Commentary:An option may be to purchase single-pair FOUNDATION fieldbus cable and use this for bothfieldbus spur wiring and for 4-20 mA device wiring.	
  	
  	
  

6.8	
  On-­line	
  Diagnostic	
  Tools	
  
	
  

	
  
	
  

	
  

Several options exist for on-line diagnostic tools: permanently attached and portable devices. The
following measurements shall be included in FOUNDATION fieldbus diagnostic tools:• Voltage per segment• Segment noise• Maximum fieldbus signal (communications) level• Minimum fieldbus signal (communications) level• Low resistance between shield and negative signal pole
• Low resistance between shield and positive signal pole
Optional measurements include:• Fieldbus jitter on the segment
If the on-line diagnostic tool is permanently installed as part of the FOUNDATION fieldbus power
supply, additional information may be available, such as:• Minimum, maximum and real-time bulk voltage supply to the FOUNDATION fieldbus power
supply• FOUNDATION fieldbus power supply operational status
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•

Minimum, maximum and real-time FOUNDATION fieldbus current

Benefits of permanently installed diagnostic tools may include the ability to historize the data, andprovide real-time alarming and trending of the data. Portable diagnostic tools assist introubleshooting specific problems and may present additional data not available with permanentdiagnostic tools. Permanently installed diagnostic tools shall only be considered if they are wellintegrated with the Host system.	
  	
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7.0	
  FIELDBUS	
  NETWORK/SEGMENT	  DESIGN	  GUIDELINES	
  7.1	
  FOUNDATION	
  Fieldbus	
  Network/Segment	
  Topology	
  
	
  

	
  

	
  

	
  

	
  

The FOUNDATION fieldbus installation shall use the tree, spur or combination topology. Other
topologies are not recommended.
Commentary:
Components of fieldbus segments can be connected together in various topologies. The topology
selected is often, though not always driven by the physical device location in order to reduce
installation costs. Hence, control narratives, plot plans and risk management considerations are usedin addition to P&IDs and instrument indexes in the design of a fieldbus segment.
Spur connections shall be connected to current-limiting connections to the bus via device couplers toprovide short-circuit protection, and allow the ability to work on field devices without a hot work permit.
The device coupler should provide a non-incendive or intrinsically safe connection to the field device.
Exceptions to this may be considered when lightning surge protection is required (see Section
7.3.5.3).
Commentary:
The drops and current limiting can be provided by device couplers in junction boxes or by device
couplers that can be field-mounted.
The connection from the marshalling cabinet/Host to the coupler(s) in the field for the topologies
shown in Sections 7.1.2, 7.1.3, and 7.1.4 are often provided by a multi-pair, individually shieldedcable of the same type (ITC) used for the individual network and spur wires. However, spur wire
may be of a smaller gauge (See Section 7.7.3).
Commentary:
Depending on whether or not segment bridging is supported in the Host, the desire to implement
control in the field may drive the need to connect all the devices for the affected loop to reside on
the same segment.

7.1.1	  Point-­to-­Point	
  Topology	
  This topology consists of a network having a maximum of only two devices. The network could beentirely in the field (e.g., a transmitter and valve, with no connection beyond the two) or it could be afield device connected to a Host system (doing control or monitoring). This topology is illustrated
below and should not be used. It is not an economical design except as listed below.	
  	
  

	
  

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Figure 7.1: Example of Point-to-Point Topology.

	
  7.1.2	  Tree	  Topology	
  (Chicken	
  Foot)	
  This topology consists of a single fieldbus segment connected to a common junction box to form a
network. This topology can be used at the end of a home run cable, and is practical if the devices on
the same segment are well separated but in the general area of the junction box. When using this
topology, the maximum spur lengths must be considered. Maximum spur lengths are discussed in
Section 7.2.4. This topology is illustrated below in Figure 7.2.

	  Figure 7.2: Example of Tree (Chicken’s Foot) Topology.
	
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This is the preferred topology to be used for reuse of existing wiring, as it is most similar to theconventional installation and will, therefore, provide the optimal use of existing infrastructure.
Tree branch topology should be used for the following situations:• Retrofit installations• High density of fieldbus devices in a particular area	
  This topology also allows maximum flexibility when configuring and assigning devices to
networks/segments.

7.1.3	  Spur	  Topology	
  (Bus	
  with	  Spurs)	
  	
  This topology consists of fieldbus devices connected to a multi-drop bus segment through a lengthof cable called a spur. This technology is technically acceptable, but generally not a good
economical choice when there is a high density of devices.

	
  

	
  

Figure 7.3: Example of Spur Topology.
Bus with spur topology may be used in new installations that have a low density of devices in anarea. Spurs shall be connected to current-limiting connections to the bus as this provides shortcircuit protection.

7.1.4	  Combination	
  Topology	
  

	
  
	
  
	
  

Combinations of the above topologies must follow all the rules for maximum fieldbus
network/segment length, and include the length of spurs in the total length calculation. These typesof topologies are preferred for designs using bricks with tray cable. Spurs are permitted to extend
only from trunk lines and not from other spur lines.
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Figure 7.4. Example of Combination Topology.

	
  

	
  
	
  

	
  

Commentary:
Care shall be taken to install the correct number of terminators with one terminator at the final device
coupler.

7.1.5	
  Daisy	
  Chain	
  Topology	
  

	
  

	
  

This topology consists of a network/segment that is routed from device to device, and is connected
at the terminals of the fieldbus device. The topology is illustrated below in Figure7.5. It should not be used, as it is unacceptable, for maintenance purposes.
Commentary:
The daisy chain topology is not used because devices cannot be added or removed from a
network/segment during operation without disrupting service to other devices. Similarly, failure of one
device will impact all other devices “downstream” of the failed field device, and signal level willprobably increase due to the loss of one terminator.

	
  Figure 7.5. Example of Daisy Chain Topology.

	
  

	
  
	
  
	
  

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7.2	
  FOUNDATION	
  Fieldbus	
  Wiring	  	
  7.2.1	
  Cable	
  Types	  	
  For information on FOUNDATION fieldbus wire and cable requirements, see Section 6.0 –Segment Design Components.

7.2.2	  Distance	  Constraints	
  

	
  
	
  

	
  

The maximum allowed length of a non-intrinsically safe FOUNDATION fieldbus segment is1900 m, provided that the cable meets the required specifications (See Section 6.7). This total
segment length is computed by adding the length of the main trunk line and all the spurs that extend
from it.
Total Segment Length = Trunk + All Spurs
Commentary:
From field experience, these lengths have been found to be conservative for high power trunks. As
stated in this specification, the length of a segment is limited by DC voltage drop, power
availability, and signal quality. As the end-user gains field experience, these length	
  limits may berevised shorter or longer to reflect real-world experience. See Section 7.7.4 for further information
on signal attenuation limits to segment length.
For trunks that limit power to meet non-incendive or intrinsically safe requirements, segment lengthand number of devices supported will be severely limited.

7.2.3	
  Home	  Run	
  Cable	
  (Trunk)	
  

	
  

	
  

	
  

	
  

Runs parallel to high power cables should be minimized, and adequate spacing and shielding shouldbe employed.
10% spare pairs should be provided for all multi-pair segment trunk cables, with a minimum of one
spare pair. This requirement includes spares on trunk cable runs between interface
enclosures/marshalling racks and junction boxes, and between junction boxes.
Commentary:
The decision to use multi-pair or single-pair trunk cabling depends on the number of
networks/segments installed in the field area. Typically, the trunk cable will be a multi-pair cable if
more than one network/segment is required in the area or the network/segment in the area would be
loaded to maximum. Facilities may have their own rules relative to spare capacity requirements uponcompletion of a project. This is suggested as a guideline in cases where a standard has not been
established. Care should be taken to land spare trunk pairs on terminals in order to avoid possible
noise interference.
When installing FOUNDATION fieldbus in a Brownfield facility, the existing home run cables shall betested for suitability for reuse. This test can be done using cable testing tools (See Section
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9).
Commentary:
Using existing cable has a risk of poor quality and requires field verification. Extra QA procedures will
identify bad cables (See Section 8)
At present, Relcom devices are the only known simple handheld test products available for thisservice.

7.2.4	  Spurs	
  

	
  

	
  

	
  

	
  

	
  

A standard specification for maximum spur length is 120 meters. However, practical experience,
formal tests and theory all confirm that 200 meters is acceptable if the cable is within Fieldbus
Foundation specifications. IS spurs have additional distance limitations depending on the IS
design style (e.g., Entity, FISCO, Multiple Fieldbus Barriers).
Commentary:
A spur is a drop-off of the main trunk line. The trunk is considered to be the main cable run and willcontain segment terminators at each end. A spur that is less than 200 meters is negligible as atransmission line and can accurately be modeled as an equivalent capacitor. Note:
Quarter-wavelength at H1 frequencies is around 2 kilometers. Strictly following the IEC 611582 Annex B wiring guide can place unnecessary and costly restrictions on fieldbus wiring.	
  	
  Only one (1) FOUNDATION fieldbus device shall be connected to each spur.
Commentary:
Since a short-circuit protection wiring block is being used, the segment design is limited to one (1)device per spur. The spur length is the length of the cable from the wiring block to the fieldbus device.
Any spur over 120 meters should require principal approval. The intent of the selected multi- drop
bus wiring method is to eliminate the need for long spur lengths and to keep spurs under therecommended length of 30 meters or less. Longer spurs may be needed to keep the bus out of highrisk areas. (e.g., hazardous Zone 1). A validation of device voltage at the long spur length shall be
performed as given in Table 7.4.

7.3	  FOUNDATION	
  Fieldbus	
  Power,	  Grounding	
  &	
  Lightning	
  Protection	
  	
  7.3.1	
  Power	
  

	
  

	
  

FOUNDATION fieldbus devices may be powered either from the segment (bus), or locallypowered, depending on the device design.
Commentary:
Bus-powered devices typically require 10-30 mA of current at between 9 and 32 volts. Any
network/segment designed to operate at less than 2 volts above the minimum required voltage at any
device or wiring component, normally should carry a warning about additional loads in the network
documentation. Minimum network/segment voltage should always be shown in the network
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documentation.
The total current draw from all devices on the network must not exceed the rating of the
FOUNDATION fieldbus power supply. The network/segment design must take into account:• Total maximum device quiescent current draw
• One spur short-circuit fault (i.e., ~50 mA additional current draw)• 15 - 25% additional current load above the two (2) previous requirements (for inrush
current and expansion, etc.)• Current consumption of wiring components• Test equipment (typically 12 mA per device)

	
  

	
  
	
  

The number of bus-powered (two-wire) devices on a segment is limited by the following
factors:• Area classification requirements• Output voltage of the FOUNDATION fieldbus power supply• Current consumption of each device• Current consumption of wiring components• Location of device on the network/segment (i.e., voltage drop)• Location of the FOUNDATION fieldbus power supply• Resistance of each section of cable (i.e., cable characteristics)	
  	
  • Minimum operating voltage of each device• Additional current consumption due to one spur short-circuit fault (~40 mA)• In-rush current caused by powering on the entire segment at once
• Segment bandwidth
Refer to Tables 7.2, 7.3, and 7.4 for calculations.
Commentary:
Current experience shows that if good quality cable is used, and if the guidelines given in thisdocument are followed, these calculations may not be necessary for all segments.

7.3.2	  Polarity	
  

	
  

Wiring polarity shall be maintained throughout the segment design and installation.
Commentary:
Wiring polarity is critical because although most fieldbus devices aren’t polarity-sensitive, some
instruments are. When wired with the wrong polarity, a device or device coupler may not operatecorrectly.

7.3.3	
  Grounding	  The instrument signal conductors must not be used as a ground. Instrument safety grounds must be
made through a separate conductor outside of the signal cable.
FOUNDATION fieldbus devices shall not connect either conductor of the twisted pair to ground at any
point in the network. The fieldbus signals are applied and preserved differentially throughout the
network.
	
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The grounding systems are generally the responsibility of the Electrical Engineering discipline andshall be as specified in other documents. The following are the specific FOUNDATION fieldbus
grounding requirements.
The FOUNDATION fieldbus cable shield shall be kept isolated from the safety grounding system except
where specifically designated connections are required as shown in Figures 7-6 through 7-9,
illustrating both non-incendive and IS applications.
Instrument signal conductors shall not be used as an earth/ground. If an instrument safety
earth/ground is required, it shall be made through a separate conductor. The conductor may be in
the same cable as the instrument signal conductors and shield, but shall be located outside theshield within this cable.
Commentary:
The earthing/grounding of either conductor would be expected to cause some or all devices on thatbus network/segment to lose communications intermittently or completely for the period that the
conductor is earthed/grounded.	
  	
  7.3.4	
  Fieldbus	
  Cable	  Shielding	
  

	
  

	
  

	
  

	
  
	
  

	
  

Shielding is a very important aspect of segment design. Various options (Classes A – D) may be
used, depending on local codes, standards and practices. These classes are illustrated in thissection and larger versions of these illustrations are given in Appendix 3 for clarity.
Class A design shown in Figure 7-6 is recommended for most regions of the world. The instrument
cable shield is terminated at the Host (fieldbus power supply) end of the network and is notconnected to ground at any other place.
Commentary:
Some device I/O shields, such as grounded thermocouples on temperature multiplexers, may
require grounding separately from the fieldbus shield. Some regions, such as Europe, prefer using
Class B design in areas where there is equipotential grounding assured.
Class C design is an alternate recommendation shown in Figure 7-8. The instrument cable shield is
terminated at the Host (fieldbus power supply) end of the network in the marshalling cabinet and isconnected to ground at field devices with isolating device couplers. It is commonly used for IS spurs
on a high-power trunk.
Class D design is not recommended.
If a multiple homerun cable goes to a field junction box, do not attach the cable shield wires fromdifferent networks together. This creates ground loops and noise onto the network.
The approaches to the grounding concepts (e.g., construction) may vary due to national standards,
but the same basic concepts (equipotential ground) are consistent worldwide. Grounding concepts
can vary depending on national standards. In Great Britain, for example, installation with central
grounding is common practice whereas in other European countries, such as Germany, a plantwide
potential matching line is usually laid. In North America, on the other hand, the cables are often
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routed in pipes (conduit) that lead to the central cabinets.
Every concept has advantages and restrictions, which are set off against the plant topology andexternal conditions such as the extension of the fieldbus, the grounding concept of the plant,interference frequencies to be expected, existing Ex areas and the need to protect the fieldbus
against lightning.
Generally speaking, in all the shielding concepts, instruments are connected to a potential matching
cable with a large cross-section, which is necessary from the point of view of explosion protection
alone. This potential matching cable runs through the plant and is grounded at one point. Dependingon the building type, a separate cable does not always have to be routed. In concrete and steel
constructions, the reinforcements and additional connection points of the constructions assume thetask of potential matching. Ultimately, the guidelines with regard to installing in hazardous areas andthe applicable national regulations also have to be observed.	
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Figure 7-6. Class A: Single-point Shielding
Single-point Shielding (Class A) requires that the shield be connect to ground at only one location
on a segment. The IEC 61158-2 recommends single-point shielding installation. The cable shield is
usually connected to the common system referencing ground (GND Reference) through the fieldbus
power supply.
The advantage of this type of installation lies in its protection against interference frequencies up toa few megahertz. Ripple frequencies in the 50/60 Hz range and multiples thereof (harmonic) areparticularly well suppressed. These frequencies can come from power cables routed parallel to thefieldbus cable.
Single-point shielding also offers protection against lightning. By separating the cable shield andplant grounding, equalizing currents cannot flow over the cable shield. Thus, if lightning strikes theplant, it cannot run through to the control system and cause damage.
Further EMC protection involves laying the fieldbus cable in a steel pipe (conduit) or armored cable
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that acts as an additional Faraday shield.	
  	
  

	
  

	
  

	
  

	
  

	
  

	
  

Figure 7-7. Class B: Multi-point Shielding
Multi-point Shielding (Class B) provides the greatest degree of protection against electromagnetic
interference, similar to conduit or armored cable, in the upper frequency range even for interferencesthat are above several megahertz. All the instrument and cable shields of the bus cable are grounded
locally which, in turn, has to be grounded in the safe area for installations in hazardous areas. Multipoint grounding provides optimal protection from a single noise source at any location.
The disadvantage of multiple grounding is seen in the event of poor equipotential ground. If goodpotential matching is not possible between the grounding points of the shield, the shield will becomea current carrying conductor and induce noise into the network. The following documents provide
guidance for defining a good equipotential ground.
ƒ IEC 60079-14 (Elektrische Betriebsmittel für gasexplosionsgefährdete Bereiche- Teil14:
Elektrische anlagen für gefährdete Bereiche (ausgenommen Grubenbaue)
Multi-point grounding provides direct connection for lightning surges back to the control room
through the signal and shield wires and may require special attention.	
  	
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Figure 7-8. Class C: Shielding Using Isolating Device Couplers.
Combined Topologies (Class C) uses a mixture of topologies from Class A (single) and Class B(multi-point) with signal isolation located in the field junction box. The mixed topology breaks up
paths for ground circulation currents and surges that may exist in the Class B topology. In thisconcept, the shield of the trunk segment from the control room to the field junction boxes is connect
to ground at a single location, typically at the fieldbus power supply. At the junction box, the trunkshield should be continuous if multiple isolated device couplers are used, but the trunk shield should
not be connected to ground at the junction box.
On the field side, the shield is connected both at the instrument and connected at the isolated device
coupler. This topology is common in hazardous areas that involve a mixture of increase safety andintrinsic safety and moves the barrier into the junction box to provide a maximum number of devices
for the segment. The trunk side maintains all of the benefits associated with Class A while the fieldside provides enhanced electromagnetic noise immunity offered by Class B.	
  
	
  

	
  
	
  

	
  

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Figure 7-9. Class D: Multi-point Shielding Using Capacitive Coupling.
Multi-point Shielding Using Capacitive Coupling (Class D) is a variation of multi-point shielding(Class B) except than an adequate equipotential ground does not exists throughout the plant site.
Similar to Class B, this topology requires the shield to be connected to ground at several points,
including the instruments and field junction boxes. However, at the control center area, the shield isconnected to ground through a coupling capacitor. The coupling capacitor is used to block DC groundloop currents that would result from a poor equipotential ground.
Similar to Class B, this topology offer better EMC susceptibility at high frequencies and blocks low
frequency currents that would be carried by the shield in a multi-point shielding.
However, a fault condition, such as a lighting strike, could result in a high voltage being
present at the Host system side. Class A, B or C is preferred topology over Class D.

7.3.5	
  Segment	
  Isolation	
  Segregation	  and	  Surge	
  Protection	
  Segment isolation is a basic requirement for FOUNDATION fieldbus design. Where devices are
installed in areas that are considered to be at a high risk of lightning strikes, segment segregation
shall be considered as an additional measure of protection. High-risk applications include tank farms
where transmitters are located on top of tanks, remote areas in open spaces, devices requiring morethan two wires (temperature), unprotected structures with little or no surrounding steel, and	
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  transmitters that are located on the top of columns or in the open on top of structures.
7.3.5.1	
  Isolation	
  FOUNDATION power supplies shall be applied with galvanic isolation between power source, groundand the segment. Galvanic isolation is required for all field devices and H1 interface cards. Isolating
spur protection is generally not required. The most common couplers for non-IS installations provide
simple analog current limiting for short circuit protection with no isolation. Couplers do not provide
lightening protection.
7.3.5.2	
  Segregation	  Transmitters that are at higher risk of direct strike or near miss may be placed on separate segmentswith no final control elements. In general, the consequences of a transmitter loss will be much lessthan the process upset or trip consequences resulting from damage to a segment with final control
elements. In this case, the risk associated with the transmitter loss does not justify the installation ofsurge protectors.
7.3.5.3	
  Surge	
  Protectors	
  

	
  

	
  

	
  

	
  

	
  

Installations where lightning is frequent, grounding is poor, and exposure is high offer more extreme
challenges for lightning protection. This may occur at tank farms, remote areas, or exposed sites inoperating units. For installations with high risk of lightning strikes and where devices are used forcontrol or associated with a control loop, the following additional measures should be considered:
Surge protection installation:
When surge protectors are applied, they shall be installed at each field device on thesegment, and at the host H1 interface. The number of devices on a segment should be kept
low and confined to a small area (<30 m2).
It is vitally important that the surge suppression device does not measurably attenuate thefieldbus signal.
Spur protection with surge protectors:
Current-limiting couplers should not be used in combination with surge protectors. The surge
protectors will cause failure of the current limiting circuits when a lightning strike occurs—even when the lightning strike is not a direct hit.
The decision to use device spur surge protection must be risk-ranked against the exposure to
the segment due to no spur over-current protection. The results of the risk ranking shall be
documented for future reference.
Commentary:
The need for surge protection versus the need for short circuit protection on a segment may
significantly alter the segment loading (device assignment). Care should be taken to ensure thebest result for the particular installation. Current-limiting and segment segregation generally
provide the lower risk than surge protectors (which preclude current limiting).

7.3.6	  Terminators	
  All terminators located in the field shall be installed in a junction box or on a device coupler.
Terminators should not be installed in FOUNDATION fieldbus devices.
	
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Commentary:
A cable signal encountering a discontinuity, such as a wire open or short, produces a reflection.
The reflection is a form of noise that distorts the original signal. A terminator, consisting of acapacitor in series with a resistor, is used at the ends of a fieldbus cable, to prevent a reflection.
Care should be taken if a multi-port H1 interface does not support disabling individual ports. All
ports may require segment terminators to be installed (an equivalent segment).

7.3.7	
  Repeaters	
  

	
  

	
  
	
  

	
  

Repeater functionality to extend the length of a fieldbus segment is not normally needed orrecommended. If an active repeater must be used, consideration should be given for thefollowing:
•
•
•
•
•
•

Redundancy
Failure mechanisms
External power requirements
Segment device count and loading
Termination requirements (both sides)
Timing through-put delays

Sometimes repeater functionality may exist in combination with IS Isolation for use in IS power
supplies or IS isolated device couplers, which would have application specific requirements.
Commentary:
Repeaters replace one of the field devices in the physical device count, allowing the addition of theequivalent of an entire new segment. By adding a repeater, a new segment is created. Repeaters canbe used to split a network into smaller segments.
If a repeater is added to the network, a new segment is connected, and the following should
apply:

	  ••The newly created segment should have terminators at both ends.
Timing limits the maximum number of repeaters in series to four (4) on a segment.

7.4	
  FOUNDATION	
  Fieldbus	
  Segment	
  Risk	  Management	
  

	
  
	
  

	
  

	
  

Although optional, each end-user facility should identify and document a risk assessment philosophy(method) by which fieldbus devices are assigned to network/segments. This is not to be confusedwith Safety Integrity Level evaluations, or other safety-related design.
The use of registered devices and wiring components is an essential part of Risk Management.	
  	
  The Segment Design Risk Assessment is an operability review process performed prior to
FOUNDATION fieldbus segment design (See Section 2.4.2).
The segment design process may use existing segment loading methods or the methodology
described in Appendix 4. The philosophy shall consider network/segment segregation, multiple
segments per H1 interface, etc. Any form of risk assessment or ranking should be clearly shown on
Revision 3.2.1- 88 -

September 2012	  the network/segment drawings or other project documents. Topology design should minimize single
points of failure.

7.5	
  Segment	  Design	
  Considerations	
  7.5.1	  Multivariable	
  Devices	
  

	
  

	
  

Multi-input and multivariable transmitters employing FOUNDATION Analog Input (AI) Function Block(s)may be used for control and monitoring. A multivariable transmitter input should be used in one
control loop only. All other variables from the transmitter can be used for monitor-only applications.
Multi-input transmitters using FOUNDATION fieldbus Multiple Analog Input (MAI) Function
Block(s) shall be used for monitor only applications.
Commentary:
MAI blocks do not utilize scheduled publish/subscribe communications (compel data) and,
therefore, do not offer the security of stale data counters in control blocks.

7.5.2	  Discrete	  Devices	
  Discrete fieldbus devices (using DI/DO Function Blocks) may be used on the same
network/segment as regulatory control and monitoring devices.
7.5.3	  Network/Segment	
  Shorting	  A shorted network/segment or power supply failure will send spring loaded valves to theirdesignated failure position, regardless of the device hosting the PID algorithm.
7.5.4	  Transmitter	
  Assignment	
  

	
  

Normal practice shall be to include the transmitter with the primary process variable on the same
segment with its associated valve.
Commentary:
This is a necessary condition to allow for field-based control. This restriction does not apply forsystems supporting bridge capability between H1 networks.

7.5.5	  Multiple	
  Process	
  Variables	
  

	
  

Multiple measurements used to provide a calculated differential shall be assigned to a common
segment with the differential calculation performed in one of the transmitters as they typically have alower “load” than an output device.	
  	
  Commentary:
This restriction does not apply for systems supporting bridge capability between H1 networks.

7.5.6	  Device	
  Diagnostic	  Alarms	
  Most diagnostic alarms from field devices require no immediate operator action. These alarms shallbe logged (auto acknowledge, no horn) for future analysis and action by maintenance personnel.
These diagnostic conditions shall also be indicated in maintenance diagnostic screens with a meansof easy navigation to indications of root cause and corrective action.

	
  Revision 3.2.1- 89 -

September 2012	
  7.5.7	  Device	  Segregation	
  

	
  

Segment design shall be such that loss of a segment does not affect more than one of the parallel(redundant/spare) process units or equipment items. Segregate segments by piece of equipment.
For example, do not combine bottom-level control for different columns on one segment even though
they are geographically close together.
•

•

	
  

	
  

Installing redundant bus/host system interface cards avoids the possibility of a commonmode failure that could fail several buses at the same time when multiple buses are
installed on a single interface card. Minimize communications between networks.
Ensure control communications remain deterministic (cyclic).

Devices that operate together shall be on the same segment in order to:
An example of this configuration is the use of a FOUNDATION fieldbus in a PID field
configuration and/or cascade loops.
Equipment with redundant transmitters for the same process measurement point shall be distributed
to reside on separate H1 segments. However, multiple measurements used to provide a calculated
value shall be assigned to a common segment. An example would be separate pressure transmittersused to calculate a differential, where the differential calculation is performed in one of thetransmitters (See Section 5.5.1 for fault handling).

7.5.8	  Combining	
  Safety	  and	
  Control	
  on	
  a	
  Segment	
  

	
  

	
  

	
  

In general, control and safety should be kept separated. The complexity (cost) of managing both typesof signals on the same segment is not worth the risk and could be much more expensive than keeping
applications separate. In any case, separation guidelines in IEC 61511 must be observed.
One use case for mixing signals is offered here and two methods of satisfying this use case example
are given. The use case is for a safety interlock to be able to override a control valve. No preferenceis stated or implied for one of these solutions. These are provided only to illustrate a point—not asrecommendations.	
  	
  Solution 1: Provide a solenoid on the control valve to provide the interlock override. The
solenoid can be actuated from the safety system without interfering with control functions.
Solution 2: Provide a serial link from the safety system to the control system to allow the control
system to override control and place the loop in a proper initialization state.

7.6	
  Limited	
  Power	
  Installations	  There are several methods for limiting power for installations in classified areas. These
include:• High power trunk with current limiting device couplers (non-incendive)• High power trunk with isolating device couplers (intrinsically safe)• FNICO (Fieldbus Non-Incendive COncept) non-incendive bus limited power (now known
as FISCO ic)• FISCO (Fieldbus Intrinsically Safe COncept) intrinsically safe bus limited power• IS Entity Concept intrinsically safe bus limited power	
  Revision 3.2.1- 90 -

September 2012	  Commentary:
For explosion proof installations, remember that you may have to power down an entire segment toperform maintenance on a device.
7.6.1	
  Fieldbus	
  Intrinsically	
  Safe	  Installations	
  

	
  

	
  

In general, the design of IS fieldbus installations must follow the same guidelines as imposed by thetechnology for non-IS installations. The major differences are the power constraints imposed by theneed to remain intrinsically safe and the requirement to use suitably certified power supplies, field
instruments and wiring components.
For IS applications, cable should:• Comply with IS inductance and capacitance limitations, as specified in the approvals
documentation. For FISCO installations, additional requirements apply to the resistancecharacteristics of the cable.
• Be identified as carrying intrinsically safe circuits. This may be by means of marking or theuse of a colored sheath.
Commentary:
Typically, IS wiring has a light blue outer jacket.

7.6.2	
  FISCO	
  

	
  

	
  

	
  
	
  

The FISCO concept has been developed to provide a means of supplying additional power to the
network/segment while still keeping the energy level below that which could cause an explosion.
Due to the limited DC power to be shared by a number of field devices, long cable runs andterminators storing capacitive energy, the traditional intrinsic safety installation and interconnection
rules restrict the application of Intrinsically Safe (IS) systems. The key advantages of FISCO,
compared with systems installed according to the conventional FF-816 “Entity” concept, are:• Higher bus current, allowing more field devices per segment	  • Elimination of cable parameter calculations• Simplification of the safety documentation—just a list of devices• Addition of new devices without reviewing the safety casePower supplies, terminators, cable and field instruments for use in FISCO systems must comply
with the requirements of Table 7.1, as defined in IEC Technical Specification IEC TS 60079-27.
Where the individual components have been designed and certified according to theserequirements and carry FISCO marking where appropriate, they may be assembled without further
approval of the overall combination. The criterion for such interconnection is that the voltage (Ui),the current (Ii) and the power (Pi), which the intrinsically safe apparatus can receive and still remain
intrinsically safe, considering faults, must be equal or greater than the voltage (Uo), the current (Io)and the power (Po) which can be delivered by the associated apparatus (power supply unit). In
addition, the maximum unprotected residual capacitance (Ci) and inductance (Li) of each apparatus(other than the terminators) connected to the fieldbus must be less than or equal to 5nF and 10µH
respectively.
Revision 3.2.1- 91 -

September 2012	  In each IS segment, only one active device—normally the associated apparatus (power supply)—isallowed to provide the necessary power for the fieldbus system. The allowed voltage (Uo) of theassociated apparatus used to supply the bus is limited to the range of 14 to 17.5 Vdc. All otherequipment connected to the bus cable has to be passive, meaning that except for a leakage currentof 50 µA for each connected device, the apparatus is not allowed to provide energy to the system.
	
  Table 7.1 FISCO Parameters

	
  
	
  
	
  

Power supplyUo	
  EEx ia IIC (Groups A-D)
Trapezoidal output
characteristic

EEx ib IIB (Groups C,D)
Rectangular output
characteristicIn	
  accordance	
  with	  IEC	
  60079-­‐11	  but	
  not	
  exceeding	
  380	  mA	  In	
  accordance	
  with	  IEC	
  60079-­‐11	  but	
  not	
  exceeding	
  5.32	
  W	
  
	
  

	
  

14	
  -­‐	
  17.5	
  V	
  

Io	
  
Po	
  
Cable	
  Cable	
  length,	
  trunk	
   	
  

	
  

	
  
	
  
5000	
  m	
  max.	
  Note	  1	
  Cable	
  length,	
  spur	
  

1000	
  m	
  max.	
  60	
  m	
  max.	
  Note	
  2	
  

Loop	
  resistance	
  R‘	
  

15	
  -­‐	
  150	  Ω/km	
  

	
  

Loop	
  inductance	
  L‘	
  

0.4	
  -­‐	  1	  mH/km	
  

	
  

45	
  -­‐	
  200	
  nF/km	
  Note	
  3	
  

	
  

Capacitance	
  C‘	
  

	
  

C' = C'conductor/conductor + 0.5 C'conductor/screen if the bus circuit is potential-free(balanced)
C' = C'conductor/conductor + C'conductor/screen if the screen is connected with
one pole of the supply unit	
  Field deviceUi

17.5 V min.

Ii

380 mA min.

Pi

5.32 W min.

Classification
Maximum
number of fielddevicesInternal
capacitanceInternal
inductance	
  Revision 3.2.1

EEx ia IIC or Ex ib IIC (Groups A-D), T4	
  32
5 nF max.
10 µH max.
- 92 -

September 2012

	
  

	
  

Terminator

80 - 120 Ω
0.8µF - 1.2µF (limited by FF specification)	  Note 1. Limited to 1,900m by FOUNDATION fieldbus.
Note 2. IEC/TS 60079-27 has a limit of 30 m; this has been increased to 60 m in IEC draft 60079/27
Ed.1/CDV, and the 60 m value is likely to be adopted in the final standard
Note 3. IEC/TS 60079-27 has a lower limit of 80 nF/km; this has been relaxed to 45 nF/km in IEC draft
60079/27 Ed.1/CDV, and the 45 nF value is likely to be adopted in the final standard
7.6.3	
  FISCO	
  ic	
  (Formerly	
  Known	
  as	
  Fieldbus	
  Non-­Incendive	
  Concept	
  (FNICO)	
  Installations	
  

	
  

	
  

	
  

It should be noted that FNICO is now known as FISCO ‘ic’. FISCO ic is a derivative of FISCO and isspecifically intended for fieldbus installations in Zone 2 and Division 2 hazardous areas. It takes
advantage of the relaxed design requirements for non-incendive (energy-limited) circuits comparedwith those for intrinsic safety. FICSO ic enjoys the same benefits as FISCO in terms of simple safety
documentation and the elimination of cable parameter calculations, and retains the ability to connect
and disconnect the field wiring in the hazardous area while under power and without “gas clearance”
procedures.
FISCO ic also has the following additional benefits compared with FISCO:• Higher levels of bus current, allowing more devices to be connected to thehazardous area trunk• Easier selection of approved field devices. Suitable devices include EEx nL,
non- incendive, IS (Entity) and IS (FISCO)• Installation rules for non-incendive wiring are less onerous than those for intrinsic safety
The requirements for FISCO ic systems are defined in IEC draft document 60079-27 Ed.1/CDV, andare expected to emerge in the final IEC 60079-27 standard, together with the requirements for
FISCO.	
  	
  The design requirements for FISCO ic power supplies, field devices, cable and terminators are
essentially the same as those for FISCO, except in the following respects:• Field wiring is classified as EEx nL in accordance with IEC 60079-15, orNorth American non-incendive• Maximum permissible value of Io is 570 mA• Field devices may have a maximum of 20 µH internal capacitance, thereby
permitting IS “Entity” certified field devices to be used in FISCO ic installations

7.6.4	
  High-­power	
  Trunk	
  Installations	
  

	
  
	
  

High-power trunks allow full utilization of maximum segment length and device capacity
without limitations due to power restriction. These designs are generally more economical than FISCO,FISCO ic and Entity.
High-power trunks may be used in Zone 1 or 2 installations to:
•
	
  

•
	
  

Revision 3.2.1

Supply power to non-incendive spurs in Zone 1 or 2 (requires current limiting
couplers as shown in Figures 7.6, 7.7 and 7.9)
Supply power to IS spurs in Zones 0, 1 or 2 (requires current-limiting couplers- 93 -

September 2012	  as shown in Figure 7.8)
7.6.5	
  High-­power	
  Trunk	
  with	  Current	
  Limiting	
  Device	  Couplers	
  (Non-­Incendive)	
  If using non-incendive wiring practices with current limiting device couplers, all equipment shouldhave appropriate zone ratings.
7.6.6	
  High-­power	
  Trunk	
  with	  Isolating	
  Device	  Couplers	
  (Intrinsically	
  Safe)	
  If using intrinsically safe wiring practices with isolating device couplers, all equipment should haveappropriate zone ratings.

7.7	
  FOUNDATION	
  Fieldbus	
  Loading	
  and	  Calculations	  	  Allowable network and segment loading is determined by the lower value of four parameters:••••

Risk management criteria (Section 7.4)
Spare capacity (Section 7.7.1)
Segment execution time (Section 7.7.2)
Voltage drop calculations (Section 7.7.3)

7.7.1	  Spare	
  Capacity	
  

	
  
	
  

The maximum number of devices on any segment (including future devices) should be no greaterthan 12. Project staff shall set a design standard for the maximum number of devices per segment forthat project if less than 12. This design standard shall be used as the basis for voltage drop
calculations and shall include spare capacity for future expansion.
Spare capacity for a segment is to be calculated based upon two conditions, with the largest
number of spare devices to be used for sizing:	
  	
  
•

	
  

•
	
  

	
  

	
  

	
  

Spare capacity should be defined as 20%. Therefore, if the maximum number of fielddevices per segment for a project is 12, taking into account spare capacity for future
expansion, the maximum number of devices to be installed into a segment shall be 10 atthe start of the project.
In all cases, segments shall be designed with adequate spare capacity for the future
addition of one control loop (e.g., one transmitter and one final element). Therefore, eachsegment shall be designed for a minimum of two future devices.

In addition, the segment macrocycle shall be designed for this future device allowance as describedabove. That is, the macrocycle shall allow one transmitter to be added (AI) and one valve positioner(final element) to be added (AO) and still ensure that the minimum free time is met (see section
7.7.2). This is based on a single macrocycle with default duration of one second. Requirements forfast execution that may conflict with this directive shall be approved by the principal.
In all spare capacity calculations, the impact on the power requirements, design of the field junction
box, segment bandwidth constraints, etc. shall be considered and sized to allow the present andfuture number of devices per segment.
Commentary:
Each Host system is different in the limitations on the number of parameters communicatedto/from a segment within a given time, and hence shall be also considered in the design of spare
Revision 3.2.1- 94 -

September 2012

	
  

	
  

segment capacity.
The maximum number of VCRs allowed per segment is less of an issue with modern day Host
systems, but may be an issue in older versions.

7.7.2	
  Segment	
  Execution	
  Time	
  

	
  

	
  

	
  

A Link Active Scheduler (LAS) is a deterministic, centralized bus scheduler that maintains a list oftransmission times for all data buffers in all devices that need to be cyclically transmitted. The LAS,
residing in the H1 interface cards, is responsible for coordinating all communication on the fieldbus (itis in charge of the token). The cycle communication is executed at fixed intervals called a macrocycle.
Segment macrocycles should match the execution times in the controller. The macrocycle shouldhave a minimum of 50% unscheduled (free asynchronous) time (see Section 4.4). Typicalmacrocycle time is 1 s.
Commentary:
By exception, a faster macrocycle may be set (500 or 250 msec), but this will impact the othersegment design parameters such as default number of devices on that segment. Alternatively, longer
macrocycles are possible. The principal shall approve such deviations from the default macrocycle
time based on a dedicated segment assessment. Loop execution time must take the location of the
PID (field or Host) into consideration.	
  	
  Do not mix control loops or control strategies with different macrocycle times (1 sec. vs. 0.25 sec.)
on the same network/segment. Mixing of macrocycle times can lead to schedules that may not bewithin the capability of some link masters.

	
  Revision 3.2.1- 95 -

September 2012

	
  

	
  

	
  

	
  

	
  

Commentary:
Having different macrocycles on the same network are also likely to make it difficult todiagnose communications problem should they occur in the future, especially if they aresporadic in nature.
Some Host systems also enable multi-scheduling within a macrocycle. Multi-scheduling allows
selected loops to run faster than the macrocycle. The principal shall approve multi-scheduling, as it
will reduce the number of devices per segment depending on the applied schedule.
For segments that only monitor measurements, limit segment to 12 devices.
Commentary:
A signal multiplexer shall be treated differently with the maximum number of multiplexers allowed
on a segment based upon the Host system constraints. In all cases, the number of signal
multiplexers shall not exceed the field device equivalents provided. The suggested maximum
numbers of devices per segment for the following listed macrocycle times are as follows:• For loops requiring 1 s macrocycle time, limit segment to 12 devices including 3 valvesmaximum• For loops requiring 0.5 s macrocycle time, limit segment to 6 devices including 2 valvesmaximum• For loops requiring 0.25 s macrocycle time, limit segment to 3 devices including 1 valve
maximum
Commentary:
For FOUNDATION for SIF segments, extra restrictions apply for stale count and extra communication
time is required for black channel communication. These considerations may further restrict the
number of devices allowed on a single segment. Calculation examples will be provided in a futurerevision.

7.7.3	
  Voltage	
  Drop	  Calculations	  Voltage drop calculations for segments shall be checked against basic rules. Only extreme segment
configurations should be validated to serve as design boundaries. All other segment configurations
less than the extreme cases can be assumed to have no voltage drop issues. For long home runs,
use 1.13 mm2 (16-gauge) cable with 100 Ω +/- 10 Ω nominal impedance.

	
  Revision 3.2.1- 96 -

September 2012

	
  

	
  	
  

Table 7.2
Step 1 - Calculation of Segment Current Draw from FOUNDATION fieldbus Power Supply
for Non IS-Based Wiring
	
  

	
  

Item

1	
  

Number	  of	
  devices	
  per	  segment	
  	
  

2	
  

	
  

	
  

Running
Total

Value
	
  

Maximum	
  number	
  of	
  devices	
  per	  segment.	
  Project	
  staff	
  may	
  set	  a	
  lower	  maximum	
  limit.	
  Average	
  current	
  demand	
   20	
  mA	
  
per	
  device	
  	
  

	
  

20	
  mA	
  is	
  a	
  typical	
  value	  3	
  Total	
  current	
  draw	
  due	  to	
  field	
  devices	
  

12	
  *	
  20	
  
mA	
  

0.24	
  A	
  

Total	
  current	
  due	  to	
  12	
  devices	
  assuming	
  each	  device	
  requires	
  20	
  mA.	  4	  Current	
  draw	  of	
  FOUNDATION™	
  Fieldbus	
  termination	
  block	  (in	
  field	
  junction	
  box)	
  	
  

5	
  mA	
  

0.245	
  A	
  

The	
  value	
  is	
  Manufacturer	
  dependent.	
  Validate	
  the	
  current	
  draw	
  for	  the	
  equipment	
  being	
  used.	
  5	
  Current	
  draw	  of	
  FOUNDATION™	
  Fieldbus	
  termination	
  block	
  when	  in	
  current	
  limit	
  for	
  one	
  
spur	
  	
  
Current	
  draw	  of	
  diagnostic	
  tool	
  	
  

60	
  mA	
  

0.305	
  A	
  

The	
  value	
  is	
  Manufacturer	
  dependent.	
  Validate	
  the	
  current	
  draw	
  for	  the	
  equipment	
  being	
  used.	
  

20	
  mA	
  

0.325	  A	
  Ensure	  that	  the	
  use	  of	  a	
  diagnostic	
  tool	  does	
  not	  result	
  in	
  voltage	
  at	
  a	
  device	  becoming	
  too	
  low.	
  7	
  Current	
  draw	
  of	
  H1	
  
interface	
  card	  to	
  the	  segment	
  

40	
  mA	
  

0.365	  A	
  Account	  for	
  redundant	
  H1	
  interface	
  cards	  (treat	  each	  card	  like	  a	
  field	
  device	
  
-­‐	
  20	
  mA)	  8	
  Total	
  anticipated	
  current	
   	
  
from	
  the	
  FOUNDATION™	  Fieldbus	
  power	  supply	  for	
  segment	
  of	
  interest.	
  0.365	  A	
  Ensure	  that	  the	  H1	  power	  supply	
  is	
  capable	  of	
  supplying	
  this	
  current	
  load.	
  

6	
  

12	
  

	
  

Comments

	
  

	
  

Revision 3.2.1- 97 -

September 2012

	
  

	
  

Table 7.3
Step 2 - Determine Voltage Drop Due to Homerun Cable (Voltage at Field Junction Box) for a
Non IS-Based Design	  Maximum ambient temperature of the cable should be considered because a temperature difference of 30° C
increases the load resistance by more than 10%.

	  Case 1: Standard FOUNDATION Fieldbus Cable – Typical Cable Specifications Used.

	
  
	
  

	
  

	
  

	
  

	
  

Running
Total
24	
  VDC	  9a	
  Voltage	  Present	
  at	
  H1	
  
card	
  

10a	
  

Cable	
  electrical	
  specifications	
  0.8	
  mm2	  (18	  gauge)	
  

21.8	
  
W/km	
  

Value	
  can	  be	
  found	
  from	  the	  Manufacturer's	
  wire	  specifications	
  

11a	
  

Length	  of	
  Home	  Run	
  

500	
  m	
  
(1640	  ft)	
  

	
  

12a	
  

Total	
  wire	  length	  of	  segment	
  (2	  x	
  length)	
  

1000	
  m	
  
(3280	  ft)	  	
  Adjust	  this	  value	
  to	
  project	  specific	
  case.	
  The	
  worst	  case	  shall	  be	
  examined	
  only	  to	
  determine	
  design	
  boundaries.	
  	
  Round	
  trip	  for	  the	
  current	
  equals	
  two	
  times	  the	
  home	  run	
  length.	
  

13a	
  

Total	  resistance	
  of	
  segment	
  home	  run	
  

21.8	
  W	
  

	
  

1000	
  m	
  *	
  (1km/1000	
  m)	
  *	
  (21.8	
  W/km)	
  

14a	
  

Current	
  draw	
  of	
  field	
  side	
  downstream	
  of	
  H1	
  
interface	
  card	  0.365	
  A	
  

	
  

This	
  is	
  the	
  total	
  load	  on	
  the	
  segment	
  as	
  calculated	
  in	
  step	
  8	
  

Item

Value

Comments
Typical	
  value	
  for	  FF	  power	  supplies.	
  Replace	
  with	  correct	
  value	
  for	
  power	  supply	  being	
  used.	
  

	
  

	
  

Revision 3.2.1- 98 -

September 2012

	
  

	
  
Case 2: Long Distance FOUNDATION Fieldbus Cable – Typical LD Cable Specifications Used.

	
  
	
  

	
  

	
  

9b	
  

Voltage	  Present	
  at	
  H1	
  
card	
  

	
  

	
  
Running
Comments
Total
24	
  VDC	  Typical	
  value	
  for	  FF	  power	  supplies.	
  Replace	
  with	  correct	
  value	
  for	
  power	
  supply	
  being	
  used.	
  

10b	
  

Cable	
  electrical	
  specifications	
  

1.13	
  mm2	  (16	  gauge)	
  14.25	
  W/km	
  Value	
  can	  be	
  found	
  from	  the	  Manufacturer's	
  wire	  specifications	
  

11b	
  

Length	  of	
  Home	  Run	
  

	
  

12b	
  

Total	
  wire	  length	  of	  segment	
  (2	  x	
  length)	
  

500	
  m	
  
(1640	  ft)	
  
1000	
  m	
  
(3280	  ft)	
  Adjust	  this	  value	
  to	
  project	  specific	
  case.	
  The	
  worst	  case	  shall	  be	
  Round	  trip	
  ofnly	  or	
  tthe	  urrent	  equals	
  examined	  o	
  dcetermine	
  design	  two	
  times	  the	  boundaries.	
  	
   home	
  run	
  length.	
  

13b	
  

Total	  resistance	
  of	
  segment	
  home	  run	
  14.25	
  W	
  

	
  

1000	
  m	
  *	
  (1km/1000	
  m)	
  *	
  (14.25	  W/km)	  14b	  Current	
  draw	
  of	
  field	
  side	
  downstream	
  of	
  H1	
  
interface	
  card	  0.365	
  A	
  

	
  

This	
  is	
  the	
  total	
  load	  on	
  the	
  segment	
  as	
  calculated	
  in	
  step	
  8	
  

Item

Value

	
  

	
  

	
  

	
  

Commentary:
For 1000 m of 0.8 mm2 (18-gauge) home run cable, the total voltage drop would exceed 14 volts
based upon the example scenario. For this size of cable, the length shall not exceed 500 m (1,640ft.).

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  Table 7.4
Step 3 - Determine the Voltage Available at the Device on Longest Spur for Non IS-Based Wiring
	
  

	
  

	
  

Item

Value

Running
Total
16.04	
  VDC	  	
  Comments17	
  Voltage	
  present	
  at	
  the	
  field	
  junction	
  box.	
  This	
  is	
  
the	
  result	
  calculated	
  in	
  
Step	
  16a	  (SWA	  cable)	
  or	
  
step	
  16b	  (LD	
  cable).	
  

	
  

Use	
  the	  result	
  of	
  step	
  16a	  (SWA	  cable)	
  for	
  this	  example.	
  

18	
  

Spur	
  Cable	  electrical	
  specifications	
  0.8	
  mm2	  (18	
  gauge)	
  21.8	
  Ω/km	  Value	
  can	  be	
  found	
  from	  the	  Manufacturer's	
  wire	  specifications.	
  Assuming	  that	  0.80	
  mm2	
  (18	
  gauge)	
  cable	  is	
  used	  for	  the	
  spur	  runs.	
  

19	
  

Length	  of	
  Spur	
  

80	
  m	
  (262	  ft)	  	
  Adjust	  this	  value	
  to	
  project	
  specific	
  case.	
  The	
  worst	  case	  shall	  be	
  examined	
  only	  to	
  determine	
  design	
  boundaries.	
  

20	
  

Total	
  wire	  length	
  of	
  spur	  (2	
  x	
  spur	  length)	
  

160	
  m	
  (525	  ft)	  	
  Round	
  trip	  for	  the	
  current	
  equals	
  two	
  times	  the	
  home	  run	
  length.	
  

21	
  

Total	  resistance	
  of	
  segment	
  home	  run	
  

3.49	
  Ω	
  

	
  

160	
  m	
  *	
  (1km/1000	
  m)	
  *	
  (21.8	  Ω/km)	  22	
  Series	  spur	  resistance	
  of	
  FOUNDATION™	
  Fieldbus	
  terminal	
  block	
  

20	
  Ω	
  

	
  

May	
  or	
  may	  not	  be	
  applicable	  depending	
  on	
  terminal	
  block	
  used	  for	
  the	
  specific	
  installation.	
  

23	
  

Total	  resistance	  associated	
  with	  the	
  spur	  23.49	
  Ω	
  

	
  

Total	
  equal	
  to	
  the	
  spur	  cable	  resistance	  plus	  the	
  terminal	
  block	
  series	  resistance.	
  

	
  

	
  

	
  

Commentary:
Using isolating couplers (intrinsically safe wiring practices) requires a similar voltage drop
calculation. However, the calculation constraints must be in compliance with local legal requirements
in addition to local site practices and the manufacturer's requirements for use of the isolating coupler.
There are various validation tools available for validation of FOUNDATION fieldbus segment
design. However, each of these tools has limitations and it is possible to have a segment	
  design
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September 2012	  that will not validate. Care shall be taken in using these tools; understand the manufacturer's
disclaimer on their use.
7.7.4	
  Fieldbus	
  Attenuation	
  Calculation	
  

	
  
	
  

Although the example calculation above and some of the segment validation tools do not calculatesignal attenuation for a segment design, it is another aspect that needs confirmation. Signal
attenuation is calculated similar to voltage drop taking into account the attenuation due to the cableand due to each device, and ensuring the total attenuation is less than the allowable according to the
FOUNDATION fieldbus specification (13.98 dB). A validation tool with an attenuation calculation feature
can be used to determine boundaries for segment design (validation of worst case attenuation).
The 1900 m limit (spur + trunk) recommended by IEC 61158-2 is a good practical limit for fieldinstallations. End-user approval is required for longer runs.
Commentary:
The distance may be theoretically possible, but there are other factors that have to be consideredsuch as signals becoming distorted as they travel on the cable. While H1 signals have beentransmitted over twisted-pair well in excess of 2 km under ideal noise conditions, this is not arecommended practice. Normally, the power voltage drop due to the resistance in the wire will
become a limitation before attenuation factors will become significant.

7.8	
  FOUNDATION	
  Fieldbus	
  Network/Segment	  Naming	  Convention	
  A consistent method for identifying all signal wires is required in any control system; this is especiallytrue for a FOUNDATION fieldbus system.

	
  

	
  

Depending on project work processes and or schedule, different numbering systems may be
employed. A preferred system is shown in the paragraphs below. However simpler sequential
numbering systems for segments may be utilized when controller assignments are not known untillate in the project.
The implemented naming convention should apply to all project elements including FOUNDATION
fieldbus. The application of fieldbus introduces new components (segments, spurs, etc.) thatneed to be captured in the applied naming convention.
The following examples are given:

7.8.1	
  Segment	  Naming	  Convention	
  
•

	
  

	
  

FOUNDATION fieldbus segments, ##-NN-MM-P where:– ## - indicates the plant number, or abbreviated name to which the segment isconnected– NN - indicates node or controller number– MM - module number– P - segment or port number

Example: CCG-01-20-P01 would represent a segment located at the CCG process unit, on
controller 01, H1 card number 20, and port 01.
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  7.8.2	
  Loop	  and	
  Instrument	  Naming	  Convention	
  Loop and instrument tagging convention shall follow location/project guidelines.
7.8.3	  Spur	  Naming	  Convention	  All spurs shall be labeled with the instrument tag name and follow the standard location andproject guidelines.	
  

	
  

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8.0	
  SITE	  INSTALLATION	  GUIDELINES	
  8.1	
  Introduction	
  

	
  
	
  

	
  

FOUNDATION fieldbus technology requires a greater emphasis on system configuration andmanagement than testing of individual devices. Therefore, instrument technicians doing loop
checking will require the following:• Training on the systems and technology that are being used
• Test equipment in accordance with Section 8.4
Fieldbus commissioning, being part of a computer network, requires a high level of communications
between the instrument/control engineers and the maintenance technicians.
Configuration of the field devices shall be carried out from the Host system fieldbus
configuration software. This is in the interest of building the database as commissioning
proceeds.
• System management support. A DCS manager shall be appointed who is responsible
for the DCS system configuration while construction and check-out work is ongoing.
– Specialist support for the systems involved.
Procedures for commissioning of a FOUNDATION fieldbus system include:
•
•
•
•
•
•
•
•

Cable continuity, grounding, and insulation tests
Field device (physical installation)
Device coupler
Fieldbus power supply
Field device connection and signal analysis
Device download/software checks (data reconciliation)
Optional bus monitor capture
Optional scope waveform capture

8.2	
  Network	
  Installation	
  The construction contractor should take care when installing the fieldbus wire networks. Listed below
are the steps to be taken during the installation.
8.2.1	
  Initial	  Cable	  Checkout	  It may be advisable to test the reel of fieldbus cable to verify cable integrity before installation.
Experience has shown that new cable irregularities are so infrequent that it is more efficient to check
cable after installation according to the cable test procedures in this section.
8.2.2	
  Cable	  Installation	
  
•
•
•
•
	
  

Revision 3.2.1

Install the trunk cable (longest cable of the fieldbus network).	
  	
  Install terminators at both ends of trunk cable. Terminators are not to be installed on a
device but on a device coupler. Terminators are to be clearly marked.
External terminators on the proper terminals in device couplers.
Install any spur lines to the trunk cable.
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•
•
•
•

Perform cable resistance and grounding tests (See Section 9.5.3, Appendix 5)Connect Fieldbus power supply, grounds, and H1 interface to the trunk cable.
Perform Segment Test Procedure (See Section 8.5.3, Appendix 5)
After completing the segment test procedure, the devices can be commissioned.

Commentary:
If terminators are installed with or in a device, they may be inadvertently removed when atechnician is servicing a device and hence affect the entire network.

8.3	
  Fieldbus	
  Segment	
  Commissioning	
  Form	  A Fieldbus Segment Commissioning Form shall be completed for each segment (see Appendix 5,
Table A5.1).

8.4	
  Test	  Equipment	
  
	
  

	
  
	
  

	
  

The instrument construction contractor shall provide test equipment required to performconfiguration, calibration, and loop checks.
Commentary:
FOUNDATION fieldbus instruments should not be calibrated because they are moreaccurate than most test equipment. FOUNDATION devices shall have their ranges andscales downloaded from the DCS after the device is connected to the segment.
Dedicated fieldbus tools shall be applied in addition to the standard test equipment used forcommissioning devices.
Commentary:
The following FOUNDATION fieldbus test equipment can be considered as minimum (the user is
encouraged to explore other products which are available or are being developed):• Relcom FBT-6 fieldbus monitor or the Pepperl+Fuchs segment tester• Rosemount 375/475 Field Communicator• Valve benchmark equipment/software• Ungrounded 200 MHz oscilloscope (segment trace capture, and segment troubleshooting).
The Pepperl+Fuchs tester has built-in oscilloscope functionality for troubleshooting.
For projects with several commissioning teams, a sufficient number of test equipment
should be available to enable fast commissioning. It should be noted that thePepperl+Fuchs segment tester, Relcom FBT-6 and Rosemount 375/475 handheld
provide various types of diagnostic information, which may require a higher level ofexpertise to use effectively. These tools should be used by dedicated teams for complex
device commissioning and troubleshooting.

8.5	
  Installation	
  of	
  FOUNDATION	
  Fieldbus	
  Instruments	
  and	
  Wiring	
  8.5.1	
  Wiring	  Splices and wire nuts shall not be allowed in instrumentation wiring circuits. Wiring
terminations shall be made at terminal strips.
	
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When pre-molded cable is used, coupler and fieldbus device ports shall be protected withtemporary plastic plugs prior to cable installation to prevent damage due to water, sand, dirt, etc.
Contractor should not install spurs until both the coupler and the field device have been
installed.
Minimum cable bend radius shall not be exceeded for all installations. Excess wire that occurs withpre-terminated fieldbus cables may be coiled. Tie wraps can be used to secure the excess cable.
Care should be taken not to pinch the wire with the cable tie.
Install individual cables to the field instruments. Complete wire tagging and wire terminations forthese individual cables.
Avoid sloppy shielding. The use of heat shrinkable tubing instead of tape is the preferred
method for isolating the shield at the signal wire terminations.

8.5.2	
  Instrument	
  Ground	
  System	  The instrument ground system shall be inspected to verify that it has been installed according to theinstallation drawings (See Figures 7-6 through 7-9).
8.5.3	
  Segment	
  Checkout	
  and	  Commissioning	
  Installation of wiring shall be carried out according to the procedure detailed below and requires thecompletion of the field wiring (trunk and spurs) before trunk wiring is connected to the FOUNDATION
fieldbus power supply.
o Install trunk cables, making sure that cable tags are installed. Check wiring for theproper color code. Tag and terminate the trunk cable in the field junction box.
Tag and terminate the trunk (segment) wiring at the fieldbus power supply plug, but DO NOT PLUG
INTO THE FIELDBUS POWER SUPPLY AT THIS TIME. The segment will be powered up after Step
1 of Table A5.1 is complete. The trunk cables shall not be connected to the fieldbus power supplies
until all devices on the segment have been properly terminated.

	
  

	
  

o Perform the resistance tests for each segment according to Table A5.1 Step 1.
Commentary:	  	
  Table A5.1 is applicable to non-isolated couplers. If isolated couplers are being utilized, a separate
procedure shall be developed to test the associated FOUNDATION fieldbus segments.
•
•
•

	
  

Revision 3.2.1

Power up the segment by plugging the segment into the fieldbus power supply (See Table
A5.1 Step 2). Log the shield to ground bus bar resistance. Care shall be taken to ensurethat no signal conductor becomes grounded, since the system is now powered.
Capture the segment diagnostics files with clip-on segment test tools (e.g., Pepperl+Fuchs
tester, FBT-6, etc.) per Table A5.1 Step 3. The diagnostics files shall be saved andcombined into a master document as a deliverable record.
For segments with isolated coupler, the previous two steps must be repeated for eachspur prior to proceeding to the next step.
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•

	
  

	
  

	
  

	
  

	
  

Commentary:
Segment trace files shall be retained for historical reference to aid in possible future troubleshooting.
They are not intended for segment acceptance. Segment acceptance will be primarily based on
conformance to the measurement requirements in Table A5.1.
•

	  The DCS Manager or his delegate shall download all devices (e.g., all blocks – Function
Blocks and Transducer Blocks) on a segment. The project shall establish procedures fordata reconciliation for Resource and Transducer Blocks.

Commentary:
This procedure assumes that the instrument has its tag name pre-configured from vendor. A device
that does not have a tag will require connection one at a time to make sure that it is communicatingwith the right device.
The FAT will have verified device Function Blocks, but Resource and Transducer Blocks will
require data reconciliation. Some vendors have not resolved data reconciliation procedures where
Host system data is downloaded over the top of configuration that has been factory entered into thedevice. For each project, data reconciliation procedures (e.g. spreadsheet comparison, frozen
device parameters) shall be established that are specific for the Host system and devices used onthat particular project.
•

	
  

	
  

Capture segment trace file with clip-on segment test tools (optional per project) inaccordance with Table A5.1 Step 4. The segment trace files shall be saved and combined
into a master document as a deliverable record.

At this time, commissioning of the fieldbus segment is complete. Check the device andsegment health using the diagnostics on the Host system and clear the error counts (ifapplicable). All above diagnostic activities shall be completed before the loop-checkprocess can begin on a segment. The procedures for assuring segment and device healthare vendor-specific, but shall be performed before proceeding to further steps. The
owner’s representative shall perform this task.

Commentary:
The Host system diagnostic check should be repeated after a period of time (nominally oneweek) to monitor any accumulation of error counts if applicable.
•

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9.0.	
  ACCEPTANCE	  TESTING	  REQUIREMENTS	
  9.1	
  Introduction	
  
	
  

	
  

	
  

This section describes the various Acceptance Testing requirements of the FOUNDATION fieldbus
portion of a DCS or Host system. This may consist of Factory Acceptance Testing (FAT), Device
Integration Testing, Site Acceptance Testing (SAT) and Segment Testing/Commissioning. Sample
procedures and requirements may be found in Appendix 8 (Acceptance Testing Procedures) andAppendix 5 (Fieldbus Segment Testing Documentation).
Commentary:
Depending on the project and the experience level of the user, these testing requirements may be
implemented separately or combined to allow the user to provide the most efficient method to verify
the FOUNDATION fieldbus aspects of the project. Experienced users may defer some of theseprocedures and use simulation applications during design and checkout hardware in the field.
Some projects may be of modular construction in which small portions of the plant are
prefabricated. These can be “packaged units” or larger areas of the plant built in a remote module
yard and then shipped to the plant site. With the testing equipment and Host system options now
available, the user has several options available for testing and acceptance.

9.2	
  Assumptions	  The testing procedures assume that the following:
•

	
  

	
  

The manufacturer, in accordance with their standard procedures, has performed pretesting of all types of field devices with the host system. These procedures are executed at
the manufacturer’s premises and are described in separate documents, which should beavailable for review during the testing and form a part of the overall set of test documents.

•

Any deficiencies observed in the manufacturer’s pre-FAT or hardware testing have been
resolved.

•

Adequate FOUNDATION fieldbus expertise and professional knowledge is available tosupport the test and to implement corrective actions if required. This may require both
Host and device manufacturer representatives.

•

For all testing other than Device Integration Testing:– Host configuration and graphics have been completed per customers' specification
with the appropriate FOUNDATION fieldbus Function Blocks assigned to the appropriate
fieldbus devices.
– FOUNDATION fieldbus device tags (including the fieldbus addresses) corresponding to
the host configuration above have been configured.	
  	
  – Sufficient devices are available to configure all typical networks. A selection ofrepresentative FOUNDATION fieldbus segments is available. Purchaser shall confirm theselected segments as being representative of the networks being installed. In addition,
segments with the highest device load, communication load, and complex strategies
shall be included.

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– Selected FOUNDATION fieldbus networks/segments are prepared (but no devices
connected). The hardware infrastructure will be checked (e.g. power, signal strength,
noise and grounding).
– FOUNDATION fieldbus simulation function for parameters in field devices can be
enabled to simulate process conditions and to evaluate alarm settings, but is notrecommended because the simulation feature can be left on inadvertently. Use themanual feature of the Function Blocks and enter a value. Simulation shall be turned off
as a default for commissioning. Some asset management systems will reportsimulation-on as an alert/alarm.
– Sufficient external terminations of the type used by the project are available.
– Final cabling and junction boxes are not used. Representative connections will bemade. The final infrastructure will be tested during the commissioning.
Commentary:
For especially long or complicated networks, the network should be simulated using reels of cablein the factory or a cable simulator, in order to more closely emulate expected field conditions.

9.3	
  Device	  Integration	
  Testing	
  Requirements:	
  

	
  

	
  

	
  

	
  

	
  

	
  

Device Integration Testing verifies that the selected FOUNDATION fieldbus field devices and wiring
components are truly compatible with the Host system (and software revision) selected and witheach other. Sufficient operation time should be allowed to ensure stability of all devices.
Device Integration Tests are especially useful in the early stages of a project when selecting the
Host system and field devices to be used and developing configuration templates as well as control
strategies. If Device Integration Tests are thorough enough, the need for testing of devices at the
Factory Acceptance Test may be reduced or eliminated.
By conducting Device Integration Testing as early in a project as possible, the user will have a firmbasis for the selection of field devices and wiring components from the technical standpoint as well
as from the commercial aspect. Potential problems can be brought to light, and work-arounds
developed early, to avoid problems during installation in the field. It also provides an excellent
opportunity for training of personnel in testing and maintenance of the devices.
Commentary:
The Interoperability Test Kit procedures provided by the Fieldbus Foundation ensures that thedevices function and communicate properly per the standards, but cannot account for the	  device
manufacturer’s design or the capabilities within the device. The end-user is advised to thoroughly
evaluate any potential field device or wiring component prior to purchase.
Specific combinations of Host systems and field devices and wiring components may require
individualized testing requirements, however, some common items for evaluation are:o Is the correct hardware and software version of the Device Under Test (DUT) represented
in the Host system DD library?
	  o Has the DUT been tested by the Host system manufacturer? What problems wereencountered?
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o Does the Device have Link Master capability and can it be easily switched to a basic
device functionality?
	  o What are the default parameter settings from the factory and what needs to be modified
for the specific project?
	  o Are “Methods” available for downloading, calibration and setup procedures? Do they
perform correctly?
	  o Is an EDDL or FDT/DTM interface available? Does it perform correctly?
	  o What diagnostic alert/alarms are available in the device?

	  o How does the Host system display or handle alerts/alarms (especially multiple
alerts/alarms)?
	  o How are RBs and TBs placed out of service (OOS) and back to automatic, etc.?

	  o For final elements, what are the options for selection of device fault state actions? As
many failure modes as possible should be simulated and observed for alarms/alert
notification.

9.4	
  Factory	
  Acceptance	
  Test	  (FAT)	
  Requirements:	
  

	
  

	
  

	
  

FAT is an essential quality assurance check to verify that all the components of the Host are
working properly. Factory Acceptance Tests are focused on verification of graphics, database,power, communications, and other system integration features and functions. The purpose of
FOUNDATION fieldbus testing is to support these host system tests. Rigorous fieldbus tests will be
performed at site, during site testing.
A substantial part of the control strategy may be executed in the field devices. Therefore, it may notpossible to test the control strategy without connecting all the FOUNDATION fieldbus devices or theuse of a simulation application that can emulate FOUNDATION Function Blocks. Fieldbus migrates
much of the system functionality down to the field level; a DCS factory test	
  will typically only test theoperator interface, particularly if the field devices are supplied by a number of vendors.
The Host system vendor shall develop a separate written test plan and test procedure for the
FOUNDATION fieldbus portion of the FAT. That plan and procedure shall have the following additions
for FOUNDATION technology:
•
	
  
•
	
  
•
	
  
•

	
  

Revision 3.2.1

Proper operation of FOUNDATION fieldbus Power Supplies (FFPS) or bulk power supplies
with separate power conditioners (if used).
Proper operation of H1 interfaces and/or linking devices.
Correct operation of field devices with the Host system (see Device Integration).
Verification of control strategies and monitoring applications, which use FOUNDATION- 109 -

September 2012

	
  

	
  
	
  

devices.
•

Transfer and display of data from field devices to the HMI or historian, etc.

Commentary:
Factory Acceptance Tests (FATs) are traditionally done with systems and sub-systems, but not withfield devices. It is not generally practical to test all field devices in a FAT. A representative sample ofthe types of field devices to be used will BE needed for a FOUNDATION fieldbus FAT. The remainder ofthe field devices will be tested during site testing. These tests are described in Section 8, which gives
detailed procedures for site testing.

9.5	
  Site	  Acceptance	
  Testing	
  Requirements	
  

	
  

	
  

Factory Acceptance Testing normally verifies that the hardware is functioning properly andthat the configuration of the system is correct, prior to leaving the manufacturer’s facility. The
system is then disassembled and packaged for shipment to the site. Site Acceptance Testing
verifies that the system has been reassembled properly and functions as it did during FAT.
Testing for site acceptance does not necessarily require a full repeat of the testing done
during FAT. It should verify that that any wiring disconnected for shipment has been rewired
properly and that no damage has been done to components during shipment.
For the FOUNDATION fieldbus portion of SAT, at least a representative sampling of the components areoperating correctly and that the necessary data paths have been restored and are also working
correctly.
Commentary:
Particular care should be taken to ensure that proper shielding and grounding methods have beenused for the final installation.	
  	
  

9.6	
  Segment	
  Testing/Commissioning	
  Requirements	  Testing and commissioning of FOUNDATION fieldbus segments does require different methods
and criteria than testing of conventional 4-20 mA loops. The wire and cable used should be of“data quality” and should be treated as such. Special attention should be paid to theinstallation of fieldbus wiring, which will avoid the majority of problems that can be
encountered in the future.
9.6.1	
  Segment	
  Testing	
  

	
  

	
  

	
  

The testing for segment wiring consists of “unpowered” and “powered” portions. These
procedures are described in Section 8 (Site Installation Guidelines).
The “unpowered” (no system power applied) portion verifies the wiring and its installation iscorrect and ready for the “powered” portion to be done. Areas tested include:• Resistance• Capacitance (if applying non-registered fieldbus cable)• Shielding/grounding
Commentary:
If the cable and wire to be used is of known quality; is a Fieldbus Foundation registered product;
Revision 3.2.1- 110 -

September 2012

	
  

	
  

and has had adequate, documented acceptance testing at the factory, the user may elect to forego
this portion of testing and proceed to the “powered” portion of testing.
The “powered” (system power applied) portion verifies that power is available to the segment,
communications to the field devices is correct, and that devices are communicating. Areas tested
include:• DC voltage level at the device• LAS signal strength• Noise levels within tolerance• Device communications

9.6.2	
  Segment	
  Commissioning	
  

	
  

	
  

	
  
	
  

	
  

With segment wiring in place and tested for correctness, commissioning of the devices may begin,
the methods for commissioning the field devices may vary with the Host system used. Once
connected to the segment with system power available and the LAS running, the device can be“assigned” to its permanent node address.
The device also requires a combination of “uploading” information, which is unique to that device, tothe Host system database and then “downloading” preconfigured information from the Host system
database to the device. The methods for data reconciliation vary with the Host system used. Careshould be taken to ensure that data is not overwritten inadvertently. With this completed, the device isthen ready for “loop-checking.”	
  	
  The traditional concept of loop checking (as used with 4-20 mA devices) can be applied or as theuser gains more experience and confidence, the benefits of digital devices (accuracy and not
requiring traditional calibration methods) will allow faster testing and acceptance.
Documentation and QC/QA procedures should be modified accordingly.
Commentary:
Segments often contain multiple loops, and because of this, it is advisable to have all field devices
either permanently wired or make provisions to ensure that testing in stages does not compromise
portions of the segment, which have been “loop checked.”	
  Revision 3.2.1- 111 -

September 2012	
  10.0.	
  FOUNDATION	
  FIELDBUS	
  DOCUMENTATION	
  REQUIREMENTS	
  10.1	
  General	  	  FOUNDATION fieldbus system design requires the same documentation as conventional control systemdesigns. However, some documents must be altered for the fieldbus architecture. Documentation
alterations, additions and deletions required for fieldbus are defined below. The minimum document,
data and drawing requirements for fieldbus installations shall include at least those specified in Table
10.1
Table 10.1 Document Requirements	
  Document

Required for
DesignAs-built For
Permanent Records

System Drawing

Yes

Yes

Segment Drawings

Yes

Yes

Segment Boundary Condition
Calculations (“Worst Case” seeSection 7)

Yes

No

Location Drawings

Yes

Optional

Instrument Index / Database

Yes

Yes

Segment Checkout Form

No

Yes

Risk Management Report

Optional

No

Device Block Parameter Default
Configuration

Yes

Yes

	
  

10.2	
  Drawings	
  10.2.1	
  Segment	
  Drawings	
  

	
  
	
  

Segment drawings shall be required. Individual loop drawings are not required, are the user’s option.
Refer to Appendix 6 for examples of H1 segment drawings. Two examples are provided; the firstusing block-style connectors and the second using terminal block connectors.
When control loops are on multiple segments or contain conventional I/O, a traditional loop
drawing is required in addition to segment drawings.	
  Both the segment drawings and loop drawings illustrated in Appendix 6 are generated from acommonly used instrument-engineering program. They are to be used as examples only.

10.2.2	
  Soft	  Data	  Soft data, including display, Function Block and configuration data, need not be shown. In addition	
  Revision 3.2.1- 112 -

September 2012	  to standard loop drawing information, segment drawings shall include the following system details:• Title block shall contain the segment number (see Section 7.8.1 for numbering).
• All segment connections inclusive of the H1 interface card and fieldbus power supply, throughthe field devices, terminations, junction boxes and terminators.
• All segment and field device tagging. All spur cables shall be labeled with the instrument
tag number.
• Terminator locations shall be clearly identified.
10.2.3	
  Location	
  Drawings	
  To accurately determine the length of spur and segment cables, instrument and junction box location
drawings may be required. This information shall be available to ensure that boundary conditions are
not exceeded for spurs and trunks (home runs).

10.3	
  Instrument	
  Index/Database	  	
  An instrument index shall identify for each device whether the device is a FOUNDATION fieldbus
instrument.
Commentary:
SmartPlant Instrumentation (SPI), formerly known as INtools (for example), is the electronic
database used widely within the industry.

10.4	
  Graphics	  Maintenance graphics should be supplied to monitor the health of FOUNDATION fieldbus devices
using the internal diagnostics of the devices. These graphics shall be accessible to Operations andMaintenance through the maintenance engineering screens. Examples are provided in Appendix
7. Functionality shall include:• The ability to navigate to diagnostics in a few clicks (not more than three).
• The overview by segment with background color code related to the process severity ofdevices on the segment.
• Second level screens identifying individual components on a segment with:– Links to device and segment diagnostics.
– Links to the devices’ detail display.
– Status of the device alarm.

10.5	
  Manufacturer	
  Documentation	  Additional documentation for FOUNDATION fieldbus devices shall include all parameters for all
resource, transducer, and function blocks, including vendor default settings and the principal's
mandated changes to manufacturer defaults.

	
  Revision 3.2.1- 113 -

September 2012	
  APPENDIX	
  1:	
  HOST	  INTEROPERABILITY	  SUPPORT	  TEST	  	
  Group 6
Host Profile Classes

NameGroup 6: Class 61
Hosts

Integrated
HostClass 62Class 63Class 64

Group 7: Class 71
Hosts

Description

Primary, on process host that manages the communication
and application configuration of all control & monitoring
devices and unlocked safety devices on a network.
Visitor Host Temporary, on process host with limited access to device
parameterization for control & monitoring devices or
unlocked safety devices.
Bench Host Primary, off process host for configuration and setup of anon-commissioned control & monitoring and unlockedsafety device.
Bench Host Primary, off process host with limited access to device
parameterization of an off-line, commissioned control &monitoring and unlocked safety device.
Safety(PRELIMINARY) Primary, on-process host that manages
Integrated the communication and application configuration of all
Hostsafety and control & monitoring devices on a network.

Notes:In addition to the profiles listed above, the hosts may be suffixed by a compliance level "a" or "b"as specified in table 2.2.1. Each compliance level will become mandatory for new campaigns as
defined by the FF-525 Host Profile Test and Registration Process.

	
  Legend
M
O

	
  

	
  

	
   P

	
   Prohibited	   ‘-’

	
   Don’t care | N/A | DNA	  This feature must be implemented in order to achieve compliance for the relevant profile.
This feature may or may not be implemented. If implemented, such will be tested and credited as part of compliancefor the relevant profile.
This feature is restricted to achieve compliance for the relevant profile. Hosts that implement multiple profiles must
demonstrate how the feature is de-activated when operating in the corresponding profile.

	
  

	
  

	
  

	
  

	
  

	
  

Mandatory
Optional

FeatureCompliance Level:
FOUNDATION H1 Device Support
H1 Device Address Assignment
Configuration of Link Master Devices
H1 Physical Device Tag Assignment
Convert Link Master to Basic Device
H1 Software Download (Device Class 3 – Cntrl &Mon.)
H1 Software Download (Device Class 5 – Safety)
FOUNDATION Distributed Application Support
Block Tag Configuration

Revision 3.2.1

Class 61
Integrated
Host
a

	
  

M
O
M
M

b

	
  

O

M

M
O
M
M

	
  

M

- 114 -

P
P
P
P

b

	
  

O

-

	
  

P

P
P
P
P

a

	
  

O

-

	
  

Class 63
Bench Host
(H1) NonCommissioned
DeviceClass 62
Visitor Host
(H1)
a

O

-

	
  

	
  

P

b

	
  

O

-

	
  

M
O
M
M

O

M
O
M
M

	
  

O

P
P
P
P

b

	
  

O

-

	
  

	
  

P

P
P
P
P
O

-

	
  

Class 71
SafetyIntegrated Host
(PRELIMINARY)Class 64
Bench Host
(H1)
Commissioned
Off-Line Device
a

O

-

	
  

	
  

-

	
  

P

	
  
	
  
	
  
	
  
	
  
	
  
	
  

	
  
	
  
	
  
	
  
	
  
	
  
	
  

	
  
	
  
	
  

	
  
	
  
	
  

September 2012

	
  

	
  
	
  

	
  

	
  

	
  

	
  

FeatureCompliance Level:
Block Instantiation
Multiple Capability Levels
Resource and Transducer Blocks
Standard (Control & Monitoring) Function Blocks(Standard Parameters of Standard and Enhanced Function Blocks)

Standard Safety Blocks(Standard Parameters of Standard and Enhanced Function Blocks)

Enhanced (Control & Monitoring) Function Blocks(Enhanced Parameters of Enhanced Function Blocks)

Enhanced Safety Function Blocks(Enhanced Parameters of Enhanced Function Blocks)

	
  

	
  

Profiled Custom Function Blocks (1)Custom Function Blocks
Configuration of Scheduled Control Function Blocks
Function Block Linking and Publication Scheduling
Safety Function Block Linking and Publication
Scheduling
Function Block Execution Scheduling
Flexible Function Blocks – Fixed OD
Flexible Function Blocks – Variable OD
Multivariable Optimization (Publisher/Subscriber)
Multivariable Optimization (Report Distribution)
Use Views for Block Detail Reads
Enhanced Parameter Download Support Services
FOUNDATION Device Description Support
DD Blocks and Parameters
DD v4 Methods execution
DD v4 Menus
DD Write Access Rights
DD v5 Visualizations, Methods
DD v5 Persistent data
DD v5.1 Device-Level Access
DD Multiple Language Support
Capability File Support
FOUNDATION Alert Configuration and Handling
Process Alert Management Configuration
Process Alert Handling and Confirmation
Device Alert Management Configuration
Device Alert Handling and Confirmation
Multi-bit Alert Support
FOUNDATION Data Quality Support
Data Quality Display in Default Block Detail Displays
Data Quality Display in Default Face-Plate Displays
Data Quality Display in Trending
Data Quality Support through Host Controller
Connections
Data Quality Recording in Historian
Data Quality Display in Custom Process Graphics
FOUNDATION Safety Support
H1 Safety Protocol and Configuration Signature
Clearing SIS Fault State
Recovery from Lost Connection Key
Report of Sync Jitter Errors
Report of Sync Drift Errors
FOUNDATION HSE Device Support
HSE D2 Device Redundancy

Revision 3.2.1

Class 61
Integrated
Host

	
  

	
  

	
  

	
  

	
  

Class 63
Bench Host
(H1) NonCommissioned
DeviceClass 62
Visitor Host
(H1)

	
  

	
  

Class 64
Bench Host
(H1)
Commissioned
Off-Line Device

O

	
  
	
  
	
  
	
  
	
  

-

	
  

	
  

O

	
  

	
  

	
  

	
  

	
  
	
  
	
  
	
  
	
  

	
  
	
  
	
  
	
  
	
  

	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  

	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  

	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  

	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  
	
  

b

a

b

a

b

a

b

M
M
M

P
M

P
M

O
M

O
M

P
M

P
M

M

M

O

O

O

O

O

-

-

-

-

-

-

-

-

M

	
  

-

O

	
  

-

O

	
  

-

O

	
  

-

O

	
  

-

O

	
  

-

	
  

-

O
O
O
M

M
O
M
M

O
O
P

O
O
P

O
O
O

O
O
O

O
O
P

O
O
P

-

-

-

-

-

-

-

-

M
O
O
O
O
O
O

M
O
O
O
O
O
O

P
O
O
P
P
O
O

P
O
O
P
P
O
O

O
O
O
O
O
O
O

O
O
O
O
O
O
O

P
O
O
P
P
O
O

P
O
O
P
P
O
O

M
O
O
O
M
M
O
O
M
O
O
O
O
O
O
O
O

	
  

	
  

	
  

M
O
O
O
M
M
M
O
M
O
O
O
O
O
O
O
O

	
  

	
  

	
  

M
M
O
O
M
O
O
O
O
P
P
P
P
O
O

	
  

	
  

	
  

M
M
O
O
M
O
M
O
O
P
P
P
P
O
O

	
  

	
  

	
  

M
M
O
O
M
M
O
O
O
O
O
O
O
O
O
O

	
  

	
  

	
  

M
M
O
O
M
M
M
O
O
O
O
O
O
O
O
O

	
  

	
  

	
  

M
M
O
O
M
M
O
O
O
P
P
O
O

	
  

	
  

	
  

M
M
O
O
M
M
M
O
O
P
P
O
O

O

O

-

-

-

-

-

-

O
O

O
O

-

-

-

-

-

-

O

	
  

	
  

O

	
  

	
  

- 115 -

-

	
  

	
  

-

	
  

	
  

-

	
  

	
  

-

	
  

	
  

-

	
  

	
  

Class 71
SafetyIntegrated
Host(PRELIMINARY)

	
  
	
  
	
  
	
  
	
  

a

O
O
M

O

	
  

	
  

-

September 2012

	
  

	
  

	
  

	
  

	
  

FeatureCompliance Level:
HSE D3 Device Redundancy
HSE Interface Redundancy
HSE LD Support: Block Parameter Access
HSE LD Support: Report Re-Distribution
HSE LD Support: Republishing
HSE Software Download (Device Class 4 - HSE)

Class 61
Integrated
Host
a

b

O
O
O
O
O
O

O
O
O
O
O
O

	
  

Class 62
Visitor Host
(H1)

Class 63
Bench Host
(H1) NonCommissioned
Device	  	  Class 64
Bench Host
(H1)
Commissioned
Off-Line Device

a

b

a

b

a

b

O

O

O

O

O

O

	
  
	
  
	
  
	
  
	
  
	
  
	
  

Class 71
SafetyIntegrated
Host(PRELIMINARY)

	
  
	
  
	
  
	
  
	
  
	
  
	
  

	
  

	
  

Revision 3.2.1- 116 -

September 2012

	
  

	
  
APPENDIX	
  2:	
  CABLE	  CHARACTERISTICS	
  A2.1	
  General	  The cable shall comply with the following requirements:
A2.1.1	
  UL	
  Listing	  The cable shall comply to one or more of the following ratings:••••

Instrument Tray Cable (ITC)
Power Limited Tray Cable (PLTC)
Tray Cable (TC)
Metal Clad Cable (MC or MC-HL)

A2.1.2	
  Temperature	
  Range	  The cable shall have a -30 to +90 ºC minimum operating temperature range.
A2.1.3	
  Optional	
  Characteristics	
  Optional ratings and characteristics shall be indicated by the manufacturer as applicable:
•
•
•
•
•
•
•
•
•
•
•
•

Exposed Run (ER)ArmoredDirect burial
Marine shipboard
Oil resistantAbrasion resistant
Weld flash resistantCutting fluid resistantJacket color (generally orange, but may be blue for intrinsically safe area use, etc.)
Wire colors (generally brown for positive and blue for negative)
Capacitance and inductance per km (for FISCO use)
Overall cable roundness (as a consideration for gland sealing)A2.2	
  Characteristic	
  Impedance,	
  Z0	
  

	
  

The characteristic impedance of each twisted pair in a cable shall be 100 +/- 20 Ohms. The
characteristic impedance shall be determined by any one of the methods described in ASTM
D4566-05 or equivalent international standard at 31.25 kHz.

A2.3	  Attenuation	
  The signal attenuation of each twisted pair in the cable shall be maximum 3.0 dB/km at
39 kHz.
A2.4	
  Wire	  The minimum trunk wire-pair size shall have a maximum resistance of 23.5 Ohms/km at 20 °C(18 AWG) per conductor. The minimum spur wire-pair size shall have a maximum resistance of
59.4 Ohms/km at 20 °C (22 AWG) per conductor. Wires shall be annealed copper, tin coated.
	
  Revision 3.2.1- 117 -

September 2012

	
  

A2.5	
  Shield	  Construction	
  Requirements	
  

	
  

Each twisted pair shall be individually shielded. The shield shall be metalized polyester tape. A
drain wire shall have a resistance less than 51 Ohms/km. If another shield construction method
is used, the manufacturer shall provide assurance that the alternate method is functionallyequivalent to the metalized polyester shield.
In a multi-pair cable, each pair is individually shielded with an overall shield and all shields are
isolated from each other.

A2.6	
  Wire-­to-­Shield	
  Capacitance	
  Unbalance	  The difference in capacitance between one wire (+) and the shield and the other wire (-) andthe shield shall be no more than 4 pF/meter average. A minimum of 30 m cable length shall be
used to test this parameter.
A2.7	
  Wire	  Twists	  Per	
  Meter	  There shall be 10 to 22 wire twists per meter for single or multi-pair cables.
A2.8	
  Minimum	  Bend	  Radius	
  The minimum bend radius of the cable shall be specified. This must consider the specified
cable temperature range and the possible loss of shield coverage due to bending.
A2.9	
  Jacket	
  Resistance	  The minimum resistance between the cable’s shield and the metal structure the cable may bein or on, when a steady voltage of 500 Vdc is applied for one minute, shall be 1 MOhm/330
meters.

	
  Revision 3.2.1- 118 -

September 2012

	
  

	
  

APPENDIX	
  3:	
  RISK	
  MANAGEMENT	
  

	
  

	
  

The following valve process effect rating and network/segment loading method should be
used as a guide and modified to suit the individual process facility. The valve andassociated measurement process effect shall be defined for prudent loading of fieldbus
segments. The following ratings should be assigned to each valve and segment.
Commentary:
The design restrictions are intended to minimize the effect of human error andinteroperability problems from affecting plant reliability. The intent of High Process
Effect designs is to keep the number and variety of devices on a network small sothat a minimum of interaction is required with the segment. Less is better, however,a unit with large numbers of dependent service valves may decide to increase themaximum number of valves to three (3) for High Process Effect.
Instruments that are part of a common reliability concept should not be on the same
network (share the same Host I/O controller) and, if possible, backplane to minimize thenumber of possible common mode failure points.

A3.1	
  Process	
  Effect	  Ranking	
  HIGH	  Criteria	
  ••Causes a system trip, which shuts down entire operating process or train or no
production for more than one (1) 8-hour shift.
And no operator action and time available to mitigate process (entire) or train shutdown.

A3.2	
  Process	
  Effect	  Ranking	
  MEDIUM	  Criteria	
  
•
•
•

Causes a system trip, which shuts down entire operating process or train but production
can be resumed on the same 8-hour shift.
Or production will be reduced to lower rates.
In this case, the process dynamics will allow the operator enough time to mitigate theproblem. Final control element can be operated manually and can be back online shortly
without process shutdown.

A3.3	
  Process	
  Effect	  Ranking	
  LOW	
  Criteria	
  
•
•

	
  

Revision 3.2.1

Will not cause short-term risk of a system trip and will not shutdown the entire operatingprocess or train.
Final control element can be in a fail position for a short time without immediate operator
action.	
  - 119 -

September 2012

	
  

	
  
	
  

FAILURE
MITIGATIONSPROCESSLEVEL 1LEVEL 2LEVEL 3

LEVEL 4

NO OPERATORACTION OR
TIME
AVAILABLE TO
MITIGATE UNIT
OR TRAINSHUTDOWN
WHEN
CONTROL LOOPFAILSLIMITEDOPERATORACTION AND
IMMEDIATE TIMETO MITIGATEUNIT OR TRAINSHUTDOWN
WHEN
CONTROL
LOOP FAILSAVAILABLEOPERATORACTIONS AND
LIMITED TIMETO MITIGATEUNIT OR TRAINSHUTDOWN
WHEN
CONTROL LOOPFAILSAVAILABLEOPERATORACTIONS AND
EXTENDED TIMETO MITIGATE UNIT
OR TRAINSHUTDOWN
WHEN CONTROLLOOP FAILS

1. UNIT or TRAINSHUTDOWN No
production for
more than one(1)8-hour shift.

HIGH

MEDIUM

MEDIUM

LOW

2. UNIT or TRAIN
CONTINUES TO
OPERATE
Production can beresumed on thesame shift.

MEDIUM

MEDIUM

LOW

LOW

3. UNIT or TRAIN
CONTINUES TO
OPERATE
Production will be
reduced to lower
rates.

MEDIUM

LOW

LOW

LOW

4. UNIT or TRAIN
CONTINUES TO
OPERATE
Insignificant impact
to production or
quality.

LOW

LOW

LOW

LOW

EFFECT
CATEGORY
▼

	
  
	
  

Revision 3.2.1- 120 -

September 2012	
  Table A3.1 Process Effect Ranking Matrix	
  Revision 3.2.1- 121 -

September 2012

	
  

	
  
Risk Management Selections	
  Redundant Controller

Required

Redundant H1 Interface

Optional

Redundant Power Supplies

Required

DC Power Supply Battery Capacity

Required - 30 minutes minimum

Redundant Power Conditioners(Fieldbus Power Supplies)
Field Backup LAS

Required
Only if a redundant H1 interface is not provided andhigh reliability is necessary

Control in Valve Positioner

Preferred for simple loops

Control in Transmitter

Only for Cascade PrimaryControl in Host

Required for Complex Loops

Valve/Segment Process Effect Ranking

Required

Maximum Devices per Segment

12 (default unless otherwise noted in section
7.4 or 7.7)

Maximum Control Valves per Segment

3 (default unless otherwise noted in section
7.4 or 7.7)

Repeaters

Requires Project Lead Engineer approval	
  Table A3.2 Network/Segment Risk Management Selections	
  

	
  

Revision 3.2.1- 122 -

September 2012

	
  

	
  
APPENDIX	
  4:	
  FIELDBUS	
  SEGMENT	  TESTING	
  	
  
A4.1	
   Fieldbus	
  Segment	
  Commissioning	
  Form	
  
	
  
	
  

Table A5.1. FOUNDATION fieldbus segment commissioning form for non-isolated coupler ortrunks only. On segments with isolated couplers, the test must be repeated for each spur.

	
  Company:
Location:
Unit:
Segment No.:
Date
Step 1: This testing is performed before the segment is plugged into the power
conditioner.
(+) to (-)
Expected > 50K ohm
Actual =(+) to shield
Expected > 20M ohm
Actual =(-) to shield
Expected > 20M ohm
Actual =(+) to ground
Expected > 20M ohm
Actual =(-) to ground
Expected > 20M ohm
Actual =shield to ground
Expected > 20M ohm
Actual =

	
  

	
  
	
  

	
  

	
  

	
  
	
  

	
  

	
  

Step 2: Plug the segment into the power conditioner.
Shield to ground
Expected < 1 ohm

Actual =Step 3: Clip a FBT-6 or P&F tester onto the segment and capture the segment
diagnostics file.
Segment Diagnostics File:
Date:
Technician:Step 4: Optionally capture a segment trace file with an oscilloscope.
Segment Trace File:
Date:
Technician:	
  	
  

	
  

Revision 3.2.1- 123 -

September 2012

	
  

	
  

A4.2	
  Sample	
  Waveforms	
  
	
  
	
  

Measure the AC waveform at the marshaling cabinet terminal block field connector.
Procedure
Set the scope to AC, 200 mV/division

Expected Result
700 mV and 900 mV peak to peak nominal

10 microseconds/division for best results and press HOLD to capture the waveform.
	
  Verify the waveform against the expected waveform shown in Waveform with Two Terminatorsand 1,000 ft. Cable (Figure A5.1). Note the differences in the signals with one terminator(Waveform with One Terminator and 1,000 ft. Cable) and with three terminators (Waveform withThree Terminators and 1,000 ft. Cable).
Right around 700 is the design normal, if you have everything per design it will come out around700. If you are as high as 1100 there is something wrong, perhaps you are missing a terminatoror something is causing a higher than normal impedance. Down around 500 or so, you may be
experiencing normal signal loss from the other end of the segment. If you start getting below
500, however, you could start dropping packets. The following figure (A4.1) shows a waveformwith two terminators and 1,000 ft. of cable. This is the expected waveform.

	
  Figure A4.1 Waveform with Two Terminators and 1,000 ft. Cable.

	
  Revision 3.2.1- 124 -

September 2012

	
  

	
  
	
  

The following figure (A4.2) shows a waveform with one terminator and 1,000 ft. of cable.

	
  

	
  
	
  

Figure A4.2 Waveform with one Terminator and 1,000 ft. Cable
The following figure (A4.3) shows a waveform with three terminators and 1,000 ft. of cable.

	
  

	
  

Figure A4.3 Waveform with Three Terminators and 1,000 ft. Cable
Revision 3.2.1- 125 -

September 2012

	
  

	
  

APPENDIX	
  5:	
  FOUNDATION	
  FIELDBUS	
  SEGMENT	  AND	
  LOOP	  DRAWINGS	
  
	
  

	
  

	
  

	
  

	
  

	
  

	
  

Four drawings are provided illustrating both FOUNDATION fieldbus segment drawings andinstrument loop drawings using two different technologies. The first two drawings are
based upon “brick” style field connectors and assume a significant distance between thedevice couplers. This layout should not be used for device couplers inside the same
junction box. In that case, the trunk line will be connected directly to the individual device
couplers.
A segment drawing (Figure A5.1) illustrates how all the devices on one segment areconnected back to the H1 interface on the Host system. Figure A5.1 shows six (6)FOUNDATION fieldbus devices that are connected onto one H1 segment.
An instrument loop drawing (Figure A5.2) illustrates all the devices associated with theimplementation of one control loop. In this case, the control loop comprises a fieldbus
transmitter (flow) and a 4-20 mA level transmitter connected to a 4-20 mA control valve.
In this instance, the loop drawing combines both current (4-20 mA) and digital(FOUNDATION fieldbus) technologies onto one drawing.
The third drawing (Figure A5.3) is another example of a segment drawing using terminal
blocks in the field junction box (versus a "brick" style connector). In this segment drawing,
four (4) FOUNDATION field devices are connected onto one segment.
The fourth drawing (Figure A5.4) is another example of an instrument loop drawing. Thistime, the level transmitter and the level control valve are implemented via FOUNDATION
fieldbus, whereas the flow transmitter is implemented via 4-20 mA. Again, terminal
blocks are used in the H1 segment implementation consistent with the associatedsegment drawing (Figure A5.3).
All drawings are output from SmartPlant Instrumentation (SPI) (previously known as
INtools) using the Enhanced SmartLoop (ESL) functionality of the wiring module. Project
specific drawings may be slightly different, depending on specific project decisions on
the representation of field devices, terminal blocks, wiring colors and field junction
boxes. However, the basic layout will be similar, given the ESL output limits.

	
  
	
  
	
  

	
  

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  Figure A5.1 Segment Drawing Based on Connectors
	
  
	
  
	
  
	
  
	
  

	
  
	
  

	
  

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  Figure A5.2 Loop Drawing for Both FOUNDATION Fieldbus and 4-20 mA Devices
	
  
	
  
	
  
	
  
	
  

	
  

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  Figure A5.3 Segment Drawing Applying Device Couplers in a JB	
  
	
  
	
  
	
  
	
  
	
  
	
  

	
  

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  Figure A5.4 Loop Drawing Applying Both FOUNDATION Fieldbus and 4-20 mA Devices

	
  
	
  
	
  
	
  
	
  
	
  
	
  

	
  

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APPENDIX	
  6:	
  MAINTENANCE	  GRAPHICS	
  

	
  

	
  

	
  

	
  

The following screens may be used as examples of maintenance documentation and navigation
for FOUNDATION fieldbus segments. These are custom, user-built graphics that can show thestatus of multiple fieldbus segments in a plant unit. Pop-up screens can show individual
segments.
The purpose of these screens is to reduce the number of mouse clicks required to navigate
through diagnostic displays from typical explorer trees while giving additional information about
device criticality and alert status (live data).
Figure A6.1 shows a typical maintenance screen shot for a process unit. The colors used are incompliance with the NAMUR 107 standard. All project FOUNDATION	
  fieldbus maintenancedisplays shall be NAMUR 107 compliant in the display of alert priority.	
  The device vendor shall provide details of device maintenance and indicate the impact ofdevice changes on other devices and/or Host system with regard to monitoring, historian
database, advanced diagnostics, calibrating and configuring, including a “help” guide.

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Figure A6.1 FOUNDATION Fieldbus Example of NAMUR NE 107 Maintenance Graphics

	
  

	
  

	
  

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  APPENDIX	
  7:	
  ACCEPTANCE	  TESTING	
  PROCEDURES	
  A7.1	
  Introduction	
  The use of FOUNDATION fieldbus will necessitate some different or modified acceptancetesting criteria and procedures. The following is meant to be a guideline only. The use of
specific Host systems and field devices and wiring components will require modified
and/or additional procedures.

A7.2	
  Device	  Integration	
  Testing	  	
  A complete functional test shall be conducted for each type of fieldbus device used in
the project (i.e., third-party products).

A7.2.1	
  Functionality	
  Test	  Procedure	
  

	
  

This test will include, but is not limited to, plug-and-play interconnectivity to the Host
system, verifying access to all Function Blocks being used in the project, actual device
operation, (e.g. stroke valves/MOVs, simulate process inputs for transmitters, etc.).

A7.2.2	
  Device	  Check	  For each device to be tested, complete at least the following steps:• Document the hardware and DD revisions of the device. Verify that corresponding DD
files are included in the Host system library. If not existing, contact the Host
manufacturer and determine the availability and add it to the library. Some Host
systems modify the files somewhat in order to ensure compatibility with their system.
Otherwise, the DDs may be obtained from the device manufacturer or from theFieldbus Foundation website.
	
  

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If the particular device (and revision) has been tested by the Host system vendor,
obtain the testing results (if possible) and check for any known problems and workarounds. Use that information to create or supplement device testing procedures.
Check that the database for this device is correctly populated (either by test criteria or
specific project criteria). It is assumed that the database is populated by an uploadfollowed by modifying the relevant ranges, alarms, units, etc. The correct database
population is checked by comparison with the relevant documents and the physicaldevice itself.
Perform a download to the FOUNDATION fieldbus device and observe that no
unexplained errors occur. Host systems will report download errors. This should
include verification that all RBs and TBs can be place Out of Service (OOS) andreturned to Automatic (Auto) correctly.
Observe and record the Link Master capabilities of the device. If it is Link Mastercapable, ensure that the capability can be toggled off or on as the project requires.
Observe and record the parameter default values as received from the factory. These
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Perform a calibration and setup for each type of FOUNDATION fieldbus device, using
inherent device methods, or dedicated EDDL or FDT/DTM wizards depending on the
Host system and available asset management tools. All calibration and setup
procedures for each device shall be documented in detail and approved by the end
user. The test shall include a calibration and setup for each type of device. Examples
include (but are not limited to) the following:

Temperature Transmitters:• Changing RTD/thermocouple types and downloading transmitter span pressuretransmitters	  Pressure Transmitters• Zeroing pressure and DP transmitters• Zeroing elevation on DP level transmitters	  Valve Positioners:• Setup and calibration of a new positioner on a control valve

	
  

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maintenance manuals, the defaults should be physically compared to the device as
occasionally changes are made to the devices and not updated in the manuals in atimely manner. A determination can then be made as to which, if any, of the default
values must be made to suit the project needs.

Create a diagnostic alert or alarm condition and observe the annunciation in the HMI.
While that alert or alarm is still active, create another separate alert or alarm conditionand observe if that condition is also annunciated.
For valves and other final elements, observe and record fault state actions available
within the device and simulate as many fault conditions as possible to emulate
communications loss or diagnostic alarm conditions.

Commentary:
The purpose of these requirements is to verify and document the standard default
condition of the device, the ease of access to calibration wizards and setup procedures
via the Host or maintenance system as well as how the device will react to potentialconditions.

A7.3	
  Factory	
  Acceptance	
  Testing	
  (FAT)	
  Develop and document procedures for the following:A7.3.1	
  H1	
  Interface	  or	
  Linking	
  Device	  Operation	
  

	
  

Using a test segment (with the types of wiring components and at least one field device
to be used on the project), connect the segment to every port on the H1 interface or
linking devices (including spares) at the terminal block designated for the field wiring or
system cable downstream of the fieldbus power supply.
Observe that the device(s) is recognized on the Host system live list.

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If power supplies or power conditioners with switchable terminators are used, verify thatthe terminator switch is in the correct position.
Verify that the DC voltage and LAS signal is within rated limits of the power supply.
Commentary:
Verification of DC voltage and LAS signal may be accomplished with hand-held test
equipment, a portable oscilloscope, or with advanced diagnostic modules (online oroffline).

A7.3.2	
  Redundancy	
  Switch-­over	
  Test	  Procedure	
  

	
  

Where redundant FOUNDATION fieldbus interface cards and/or power supplies are used,
the redundant operation of each component shall be tested. The test shall verify that
automatic fail over shall not cause an upset (i.e., signal bumps, loss of operator view,mode changes, etc.). All FOUNDATION fieldbus interface cards and power supplies shallbe tested.
All failure alarms shall be tested and signed off.

A7.3.3	
  Field	
  Device	  Operation	  If separate Device Integration Testing is not performed prior to FAT, then use theprocedures described in Device Integration (Section A8.2) above.
A7.3.4	
  Data	  Reconciliation	
  

	
  

	
  

	
  

For each configured parameter residing in the FOUNDATION fieldbus devices (e.g. in TB,
AI, PID or AO block), complete the following steps:• Verify the appropriate scale and engineering units are configured as needed in both
the AI (AO) Function Block and in the Transducer Block.
• Verify that the scale and engineering units are correct and consistent for the• FOUNDATION fieldbus device and the associated faceplate, graphics and trends.
• Verify that all engineering units in the Transducer Block are consistent with the project
standards. In particular, engineering units used for diagnostic and not for graphics may
be overlooked and require extensive rework if not detected at the device integration
test.
• Simulate a process variable equal to half the scale and verify.
• The process variable appears correctly within the PV parameter field of the AI (AO)
block.	
  • The same value appears where the PV parameter is configured on a process graphic.
• The same value appears where the PV parameter is configured on a (historical) trend.
For the same device, generate a PV (if more than one is used, check every parameter
separately) that exceeds the applied alarm limits and verify that the pre-configured
alarms appear at the operator and/or maintenance workstation.
If the device is a valve positioner, complete the following steps:•

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Verify that the PID block is in MAN mode.
Manually enter the controller output on the controller faceplate.
Verify the valve positioner maintains the same output.

A7.3.5	
  Verification	
  of	
  Control	
  Strategies	
  and	  Monitoring	
  

	
  

Verification of control strategies and monitoring applications using FOUNDATION fieldbus
devices can be difficult during a normal FAT, since it is not practical to provide allnecessary field devices (especially if control in the field or other specialized Function
Blocks are used). They can be accomplished with simulation software (if available fromthe Host system manufacturer) or simple monitoring loops can be verified using more
simple methods as described in Data Reconciliation (Section A8.3.4) above.
Specific procedures should be developed and documented by the Host systemmanufacturer.
A selection of segments shall be tested which will cover all device types, the heaviest
loaded segments, and a representative selection of typicals. The selected segments
shall be tested in accordance with the segment check procedure (Section A8.5.1)
below.

A7.3.5.1	
  Transfer	
  of	
  Data	  to	
  HMI	  or	
  Historian	
  

	
  

As with control strategies and monitoring applications, verification can be difficult.
Simulation applications (if available from the Host system manufacturer) may be used or
the simple methods described in Data Reconciliation (Section A8.3.4) above, such as
placing an AI block in manual and typing in a value.
Specific procedures should be developed and documented by the Host systemmanufacturer.

A7.4	
  Site	  Acceptance	
  Testing	
  Requirements	
  Unless specifically warranted, a full re-test of the FAT is not necessarily required. A
representative sample of components should be chosen to repeat some of the testingfrom FAT. An example would be to test only one port on each H1 interface or linking
device in order to ensure that the system had been properly reassembled.

A7.5	
  Segment	
  Testing/Commissioning	
  Procedure	  Each segment, including spares, shall be operationally tested by live connection of atleast one but preferably all devices. The device shall be connected to the terminal block
designated for the field wiring or system cable downstream of the fieldbus powerconditioning module (FPPS).
A7.5.1	
  Segment	
  Check	  For each selected FOUNDATION fieldbus segment to be tested, complete the following
steps:• Complete segment testing and commissioning.
• Test/confirm that the Host system and devices have the same firmware/software
revisions.
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Test/confirm that all H1 interface cards used in the Host system are the same
firmware/software revision.
Check that the relevant segment communication parameters are correct and that themacrocycle duration has been set for each network.
Check that the power-conditioning module (generally an FPPS) operates correctly andthat a failure is communicated to the Host system.
Check that the network/segment recovers from a short circuit.
Measure the overall current consumption.
Check that the FOUNDATION fieldbus Host system interface module operates correctly
and that a failure is identified by the Host system.
Check that the Back-up LAS is functioning and is executing the correct schedule.
This only applies if Back-up LAS will be applied (i.e., for segments with CIF); in allother cases, no Back-up LAS (BLAS) is required and this test can be omitted.
Monitor stable operation for at least 12 hours.
Check the communication load under stable (no download) condition. A
load of less than 70% will be required. The Host system might supply thisinformation.
Ensure sufficient spare capacity is provided by connecting two extra
fieldbus devices and observing proper operation of the full segment.

Commentary:
Some of the segment check may have previously been tested (such as verification of
the operation of H1 interfaces), and therefore may be omitted by the user.

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