3210-8550-fs-0008 foundation fieldbus functional requrement

JOINT PROJECT MANAGEMENT TEAM PROJECT SPECIFICATION A

FOUNDATION FIELDBUS FUNCTIONAL

REQUIREMENTS 3210-8550-FS- 0008

PAGE : 2 of 34 REV : A1

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CONTENTS

SECTION SUBJECT 1 SCOPE .................................................................................................. 4 2 PURPOSE.............................................................................................. 4 3 DEFINITIONS AND ABBREVIATIONS ................................................. 4 3.1 Definitions ............................................................................................ 4 3.2 Abbreviations ....................................................................................... 7 4 FIELDBUS SYSTEM OVERVIEW ......................................................... 9 4.1 Project Objectives ................................................................................ 9 5 FIELDBUS APPLICATION .................................................................... 9 5.1 Field Device Selection ....................................................................... 10 5.2 Critical Loop Definition and Application ........................................... 12 5.3 Control Assignment ........................................................................... 13 5.4 Segment Grouping ............................................................................. 13 5.5 Temperature Multiplexer Transmitters ............................................. 13 5.6 Hazardous Area Classification .......................................................... 14 5.7 Redundancy........................................................................................ 14 5.8 Segment Physical Device Loading Requirements on the H1 bus ... 15 5.9 Segment Spare Philosophy Requirements........................................ 15 5.10 Segment Execution Time Requirements........................................... 15 5.11 Segment Wiring Design Requirements ............................................. 15 6 INTOOLS REQUIREMENTS................................................................ 19 6.1 INtools Parameters Configuration ..................................................... 20 6.2 Fieldbus Tag Numbers ....................................................................... 22 6.3 Fieldbus Segments............................................................................. 23 6.4 Fieldbus Wiring .................................................................................. 23 6.5 INtools Fieldbus Validation................................................................ 24 6.6 Diagnostics......................................................................................... 25 6.7 Testing................................................................................................ 25 6.8 Device Maintenance .......................................................................... 26 6.9 Workstations ...................................................................................... 27 6.10 Alarm and Message Handling ........................................................... 27 7 DOCUMENTATION REQUIREMENTS ............................................... 28 8 FIELDBUS SYSTEM DESIGN GUIDELINES ....................................... 30 8.1 General ............................................................................................... 30





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8.2 Main Differences between Fieldbus & Traditional Installation........ 31





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1 SCOPE

This project procedure defines the Foundation Fieldbus System Design Requirements for the Paradip Refinery Project for the Indian Oil Co. Ltd. Orissa State, India.

Any deviation from the philosophies, criteria and/or standards within this procedure shall be subject to approval by PMC/IOCL.

2 PURPOSE

The purpose of this specification is to define the Foundation Fieldbus System Design Requirements to:

• Ensure consistency across the entire project

• Minimise the design effort required by all parties

• Minimise the validation requirement

• Minimise commissioning related problems

3 DEFINITIONS AND ABBREVIATIONS

3.1 Definitions 3.1.1 General

The following defines the meaning of specific words used in this specification:

Contractor / Vendor Means the firm, company or other corporate entity (including its successors and / or permitted assigns) contracted to supply the Equipment / Services to IOCL

IOCL Means Indian Oil Corporation Ltd. And its legal successors and assigns

Shall Refers to a mandatory requirement

Should Refers to a recommendation





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May Refers to one acceptable course of action.

3.1.2 Foundation Fieldbus Definitions

The following represent definitions of Fieldbus terms used within this procedure, however, a comprehensive list of definitions can be found at the Foundation web site www.Fieldbus.org.

Term Definition

Bus A H1 Fieldbus cable between a host and field devices connected to multiple segments, normally through the use of repeaters.

Common File Format (CFF)

A software file used by the Host to know the device detailed FF capabilities without requiring the actual 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 the meaning of data in the VFD.

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 and high-speed factory automation applications.

FF device (Fieldbus device)

An H1 Field Device is a FF device connected directly to an H1 Fieldbus. Typical H1 Field Devices are valves and transmitters.

FISCO Fieldbus Intrinsically Safe Concept. Allows more power to an IS segment for approved FISCO devices, allowing for more devices per IS segment.

H1 H1 is a term used to describe a Fieldbus network operating at 31.25 kbit/second.

HIST Host Interoperability Support Testing performed by the Foundation to approve Host conformance to the FF specifications.

http://www.fieldbus.org/





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Term Definition

Interchangeability Interchangeability is the capability to substitute a device from one manufacturer with that of another manufacturer on a Fieldbus network without loss of functionality or degree of integration.

Interoperability Interoperability is the capability for a device from one manufacturer to interact with that of another manufacturer on a Fieldbus network without loss of functionality.

ITK Interoperability Test Kit used by the Foundation to tick mark devices

Link A Link is the logical medium by which FF devices are interconnected. It is composed of one or more physical interconnected segments. All of the devices on a link share a common schedule which is administered by that link's current LAS.

Link Active Scheduler (LAS)

A Link Active Scheduler (LAS) is a deterministic, centralized bus scheduler that maintains a list of transmission times for all data buffers in all devices that need to be cyclically transmitted. Only one Link Master (LM) device on an H1 Fieldbus Link can be functioning as that link's LAS.

Link Master (LM) A Link Master (LM) is any device containing Link Active Scheduler (LAS) functionality that can control communications on an 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.

Resource Block (RB) A Resource Block (RB) describes characteristics of the FF device such as the device name, manufacturer and serial number. There is only one Resource Block (RB) in a device.

Schedules Schedules define when Function Blocks (FBs) execute and when data and status is published on the bus.

Segment A Segment is a section of an H1 Fieldbus that is terminated in its characteristic impedance. Segments can be linked by Repeaters to form a longer H1 Fieldbus. Each Segment can include up to 32 H1 devices.

Spur A Spur is an H1 branch line connecting to the Trunk that is a final circuit. A Spur can vary in length from 1 m (3.28 ft.) to 120 m (394 ft.).





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Term Definition

Standard Function Block (FB)

Standard Function Blocks (FBs) are built into FF devices as needed to achieve the desired control functionality. Automation functions provided by Standard FBs include Analogue Input (AI), Analogue 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 fixed and defined by the specifications.

Terminator A Terminator is an impedance-matching module used at or near each end of a transmission line. Two Terminators must be used on each H1 segment.

Tick Marked Tick marked FF devices are those with validated compliance with Foundation Fieldbus specifications: ITK. The resource block contains the device approved ITK level.

Topology The Segment structure; Tree, Daisy Chain, etc. are examples.

Transmitter A Transmitter is an active FF device containing circuitry, which applies a digital signal on the bus.

Trunk/Home-run A Trunk is the main communication highway between devices on an H1 Fieldbus network. The Trunk acts as a source of main supply to Spurs on the network.

3.2 Abbreviations The following list gives the used abbreviations in this document.

Abbreviation Description

AI Analogue Input

AO Analogue Output

AWG American Wire Gauge

CCR Central Control Room

CFF Common File Format

DCS Distributed Control System

DI Discrete Input

DD Device Description





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Abbreviation Description

DO Discrete Output

EI Early Involvement

EPC Engineering, Procurement & Construction

ESD Emergency Shutdown

FB Function Block

FDAS Fire Detection and Alarm System

FF Fieldbus Foundation

FISCO Fieldbus Intrinsically Safety Concept

GDS Gas Detection System

HART Highway Addressable Remote Transmitter

HIST Host Interoperability Support Testing

HMI Human Machine Interface

IAMS Instrument Asset Management System

INtoolsTM Control & Instrumentation Database System

I/O Input/Output

IS Intrinsic Safety

ITK Interoperability Test Kit

LAN Local Area Network

LAS Link Active Schedule

MAI Multiplexed Analogue Input

MOV Motor Operated Valve

PID Proportional / Integral / Derivative Control

PLC Programmable Logic Controller

SRR Satellite Rack Room

UOM Units Of Measurements

UPS Uninterrupted Power Supply

All field instrumentation purchased and installed with Foundation Fieldbus must meet the minimum applicable requirements set forth by the International Electrotechnical Commission (IEC) applicable standards listed below.





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Material or equipment supplied to this specification shall comply with the latest edition of the references listed below, unless otherwise noted.

International Electrotechnical Commission

IEC 61158-2 Foundation Fieldbus Standard for Use in Industrial Control Systems - Physical Layer Specification and Service Definition

National Fire Protection Association

NFPA 70 National Electrical Code

4 FIELDBUS SYSTEM OVERVIEW

4.1 Project Objectives The Distributed Control System for the Paradip Project will be based on the Open System Architecture concept with Foundation Fieldbus (FF) interfacing capabilities to smart devices in the field.

5 FIELDBUS APPLICATION

The use of Fieldbus shall be maximised for all regulatory process control devices where a suitable FF device is available and in addition, shall also apply to all Packaged Equipment. The regulatory process control loops shall typically include the following:

• Monitoring loops (including bearing temperatures)

• Multiplexed temperature monitoring loops (Excluding bearing temperatures)

• Simple PID loops

• Cascade loops

• Sequence loops

• Complex loops

Deviation from the above shall be subject to JPMT/ IOCL approval on a case by case basis.

Fieldbus shall not be used for the following applications:

• Emergency Shutdown Systems, Fire Detection and Alarm System (FDAS) and Gas Detection System (GDS) signals due to safety reasons

• Discrete signals, i.e. digital signals due to limited availability and lack of enhanced functionality of such devices.





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• Analogue DCS type inputs defined as critical control closed loops (i.e. loops which may lead to shutdown).

• FF junction box in a Zone 1 Area. The field junction box shall be located in a Zone 2 or safe area.

5.1 Field Device Selection 5.1.1 Interoperability

The Fieldbus devices have to be fully interoperable with the DCS, including maximising of the associated advanced diagnostic features coupled to asset management capabilities within DCS System.

Based on the above objective, the following selection method shall be applied for Fieldbus devices excluding valve positioners (in order of preference):

Any other FF device and/ or positioner shall, as a minimum, have the following ‘features’ available:

• Foundation Fieldbus Certification as having passed the Interoperability Test Kit (ITK), revision 4.01 (or later) and are listed on the approved devices list maintained on the FF web site: www.Fieldbus.org

• The FF device shall be capable of performing continuous diagnostics, including self-test functions, to provide specific diagnostic information to the Asset Management System.

In addition, a ‘sample’ device shall be submitted to DCS Supplier for interoperability testing with both the DCS and IAMS systems (unless not already proven). On successful completion of these tests, JPMT/ IOCL shall provide the necessary approval for use and shall update the ‘Approved Device Listing’ accordingly.

5.1.2 Fieldbus Function Blocks

The Function Blocks (FB) as defined by the FF is grouped into Standard, Enhanced and Additional blocks, but not all of these FB’s are appropriate for use in field devices, and some are not available and/ or do not have interoperability tests.

In order to simplify the process of FF device procurement, the Contractor does not need to specify any additional FB functionality other than as follows:

• Transmitter - AI for each required process variable

• Positioners - AO

• Temperature Multiplexers - MAI

However, if the device is a valve positioner, then the device shall be specified and delivered with ALL available FBs including advance diagnostic FBs.

All function blocks supplied with the device shall be instantiated by the device manufacturer.





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In addition, these devices will be specified and delivered to site with the following default parameters settings:

Parameter Setting

• Boot_Class - BASIC (For all FF devices)

• STATUS_OPT (Propagate Fault)

Monitoring loop - AI Propagate Fault Forward: OFF

Local Control loop - AI Propagate Fault Forward: ON

- AO Propagate Fault Backward: ON

• Pressure & Differential Pressure Transmitter

L_TYPE - Direct

PV_FTIME - 2 sec.

• Level Transmitters

L_TYPE - Indirect

PV _FTIME - 2 sec.

• Flow Transmitters

L_TYPE - Indirect SQRT

PV_FTIME - 2 sec.

AI block execution time shall be better than 45ms and PID block execution time shall be better than 60msec.

5.1.3 Field Device Management

The Physical Device (PD) Tag must be set prior to installation to enable connection of multiple devices during construction and commissioning. This shall be achieved either by the device manufacturer, prior to shipment, or the EPC prior to connection.

5.1.4 Field Device Power

FF devices may be powered either from the segment, or locally powered, depending on the device design.

Bus-powered devices typically require 12 – 30 mA of current at between 9 and 32 volts, but devices requiring more than 30 mA shall be subject to PMC/IOCL approval.

FF devices should be polarity insensitive.

Externally powered FF devices shall be specified with isolation between external power and Fieldbus signal inputs.





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For this project, the bus-powered method shall be preferred.

5.1.5 Link Master Devices

No FF device needs to be specified to have the Link Master capability, as the redundant H1 interface cards within the DCS will provide both the active and back-up LAS functionality.

5.1.6 Device upgrading

FF devices use internal software of a certain revision. At present FF device software is quite often improved and upgraded, while the hardware is left unchanged.

To accommodate easy device upgrading, the devices shall, where available, be specified to have flash memory that can be on-line flashed with the latest device software (firm-ware).

Furthermore it is essential to record the applied device revision, DD and CFF revision.

The Contractor shall, in addition, to the normal Instrument Data Sheet(s), provide the FF devices detail as per the INtools Fieldbus Data Sheet.

5.2 Critical Loop Definition and Application The Contractor shall classify; by HAZOP study, control loops into 3 criticality levels. The study should take into consideration factors such as the material and energy capacity of associated vessels, geographic location, and elevation/ accessibility of valves.

Level 1 Failure of a control loop will result in a shutdown of an entire plant, or damage to non-spared vital or essential equipment.

Level 2 Failure of a control loop will result in an emergency situation, where prompt operator action would be required to “save” the plant from imminent total shutdown

Also, failure of a level 2 control loop will result in a shutdown of the entire plant, but where process dynamics allow time for quick recovery from the failure.

Level 3 Failure of this loop will not result in any short-term risk of total unit shutdown. Level 3 valves can go to their fail position.

All loops that fall into the Level 1 or Level 2 category shall not use Fieldbus technology.





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All loops that fall into the Level 1 or Level 2 category shall use Smart (Hart protocol) field instruments and valve positioners.

4-20mA shall be used for AI/ AO signals with the HART signal superimposed.

Level 3 control loops can reside on H1 segments with the following limitations:

• Up to 3 FF valve positioners per H1 segment. • Total FF devices (Txs and positioners) not to exceed 10 (inclusive of

spares) • Note that the number of control and critical loops per segment is given on

the basis of loop criticality and macrocycle requirement of the segment. • Indicator, monitoring only loops may be assigned to Fieldbus segments

freely up to 10 loops (inclusive of spares) per segment.

5.3 Control Assignment Control on the wire may be considered for simple control loops where the control valve and transmitter associated are on the same segment.

Generally the control function blocks for these loops shall be located in the positioner of the control valve.

For complex control loops (more complicated than a simple cascade loop) or control loops where the transmitter and control valve are on different segments the control function blocks shall reside in the DCS.

Where control is to be implemented in the field device, contractor is to provide justification to JPMT/IOCL for this strategy over implementing control in the DCS.

5.4 Segment Grouping In order to maximise the benefits from FF technology, grouping all devices of a particular control loop within the same segment is preferred. For cabling reasons it is allowable to host control loops across different segments, however this is not preferred. In all cases the Contractor is responsible to ensure that the speed of response for the loop is not unduly impacted by the use of Foundation Fieldbus.

Control loops shall not be split across different segments where the segments are connected to different DCS processors without approval of the JPMT/ IOCL.

5.5 Temperature Multiplexer Transmitters 5.5.1 FF temperature multiplexer transmitters may be used where high density

temperature measurements are required for DCS indication, excluding rotating machinery bearing temperature measurements. Temperature multiplexers shall not be used for control without permission of JPMT/ IOCL.

Two different methods of segment design may be implemented:

• Where additional monitoring devices can be connected to a segment, as defined in section 5.2, the quantity of temperature multiplexer transmitters





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shall be limited to three per segment. The Contractor shall take the following into consideration:

• Communication of the temperature signals from the MAI FB will be performed during the unscheduled communication period of the macrocycle and a delay of up to four seconds may be experienced between a change in measured variable and when that change is displayed at the HMI. The Contractor shall ensure this delay is acceptable for the particular process application.

The Contractor may also dedicate a segment to be used for temperature multiplexers only; in this case eight multiplexers may be connected to one segment, leaving two spare ways for future use.

The failure of an individual temperature multiplexer shall not impact on the ability to monitor an item of plant equipment, to ensure this the Contractor shall allocate measurements to different multiplexers, each connected to separate FF segments. Where the density of temperature measurements makes this approach uneconomic, the design shall revert to individual FF temperature transmitters.

5.6 Hazardous Area Classification Refer to specification 3210-8550-SP-0001 ‘Instrumentation for General Hydrocarbon and Utility Services’, for details regarding hazardous area protection preferences.

For the Foundation Fieldbus implementation the field instruments shall generally be certified intrinsically safe suitable for the hazardous area. The Foundation Fieldbus topology recommended utilises an increased safety trunk (EExe) to Foundation Fieldbus Field barriers located in stainless junction boxes in Zone 2 and intrinsically safe field instruments (either entity or FISCO certification acceptable if suitable for the hazardous area in which they are located).

5.7 Redundancy The host system DCS shall incorporate the following redundant equipment to enhance the overall availability:

• Redundant DCS Bulk Power Supply Feeds

• Redundant DCS System Controller Power Supply units

• Redundant DCS System Controllers

• Redundant FF H1 Cards

• Redundant FF Power / Conditioners

FF Segments with monitoring devices only shall use redundant H1 Cards to allow for the possibility of future inclusion of level 3 control loops to the segment.





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5.8 Segment Physical Device Loading Requirements on the H1 bus The FF specification states that a maximum of 32 devices per segment can be connected. In practice it is demonstrated that only up to 16 devices per segment are feasible.

In order to minimise the Fieldbus design effort, e.g. validation and commissioning related problems, the number of devices shall be limited to 10 devices (inclusive of spares) per segment.

The Contractor shall ensure that the loading on the segment does not impact process operability or necessary speed of response for the DCS system and field instruments selected (This may limit the number of devices to less than 10).

5.9 Segment Spare Philosophy Requirements The total number of devices per segment will not exceed 10 as detailed in section 5.8. However, to include for the 20% pre-wired spare capacity, the maximum number of installed devices shall be 8 per segment.

Deviation of the above maximum number of 8 devices requires JPMT/ IOCL approval.

5.10 Segment Execution Time Requirements 5.10.1 Segments Used For Regulatory Control or Monitoring

All segments will operate with a macrocycle of 1 second or better as specified by process licensor requirements (including an idle time of more than 500mS per macrocycle).

Any deviation to the above will require additional validation and shall be subject to JPMT/ IOCL approval.

5.10.2 Segments Used For Temperature Multiplexer Transmitters

Temperature multiplexers shall only be used on segments dedicated for use of temperature monitoring only.

The segments used for temperature multiplexers shall operate with a macrocycle of up to 4 seconds with an idle time of more than 60 % (process variables are typically transmitted during idle time for multiplexers). Exact macrocycle times to be reviewed with the selected DCS supplier to minimise the macrocycle time as much as possible.

Any deviation to the above will require additional validation and shall be subject to JPMT/ IOCL approval.

5.11 Segment Wiring Design Requirements Overall Wiring Design Philosophy





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For a traditional implementation the trunk cable between the marshalling and the field junction box is typically a 20 pair twisted cable with overall screen. The junction box can then accommodate up to 20 field devices including the 20% spare philosophy.

In order to simplify the Fieldbus implementation, the field end shall mimic the traditional implementation method as follows:

• The trunk cable shall be a 3 pair overall and individually screened cable with the 1st pair used for the 1st H1 Segment, the 2nd pair for the 2nd H1 segment and the 3rd will be an installed spare.

• The field junction box shall therefore accommodate 2 off H1 segments with each accommodating up to 10 FF devices as detail in section 5.8 and section 5.9

• Each FF device shall be connected to the Fieldbus junction box via a single pair screened spur cable

Any deviation from the above described arrangement shall be subject to approval by JPMT/ IOCL.

5.11.1 Topology

The Chicken-Foot or Tree topology consists of a Fieldbus segment connected to a common JB via the trunk cable from the Marshalling Cabinet as detailed below.

Example of Tree (Chicken Foot) Topology

H1 Card

PSU Fieldbus Junction Box

Trunk Cable

Spur Cables

In order to simplify the Fieldbus implementation effort, this topology which mirrors a traditional implementation method, shall be used.

Any deviation from the above shall be subject to approval by JPMT/ IOCL.

5.11.2 Cable Type





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In order to get maximum performance for Fieldbus network, individually shielded twisted-pair cable designed especially for FF may be used (see table 5.11.2 (1) for typical cable characteristics).

Table 5.11.2 Typical FF Cable Characteristics per IEC Physical Layer Standard

Wire Size 18 AWG (0.8 mm²)

Shield 90% coverage

Maximum Attenuation 3 db/km at 39 kHz

Maximum Capacitance 150 pF/m

Characteristic Impedance 100 Ohms +/- 20% at 31.25 kHz

Maximum dc Resistance 22 Ohms / Km

However, specially designed FF cable does not provide significant benefits over standard cable that is available at a more attractive price and as such, for this project standard instrument cables shall be used as follows:

Cable Type Specification (BS 5308 Part 1 or better)

Trunk Cable - Two twisted pairs, PE insulated, overall and individually screened, SWA, PVC sheath, 1.0mm²

Spur Cable - Single twisted pair, PE insulated, screened, SWA, PVC sheath, 1.0mm²

5.11.3 Cable Length

According to the FF specification (ISA S50.02) the maximum allowed length of a Fieldbus segment is limited to 1900 metres. 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

From experience it is found that these lengths are conservative. The length of a segment is limited by voltage drop and signal quality (i.e. attenuation and distortion).

In order to eliminate the need to calculate the physical loading of each segment and to reduce the validation requirement, the following limits shall apply for this project:





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• Trunk cable length ≤ 750 metres

• Spur cable length ≤75 metres

Any deviation from these lengths shall be subject to JPMT/ IOCL approval.

5.11.4 Power Consumption

The maximum segment current is limited to 350 mA by the segment power conditioners.

For this project, the maximum current required by a FF device shall not exceed 30mA (see section 5.4.4).

5.11.5 Minimum Operating Voltage

For this project, minimum voltage at the FF device shall be 10 Vdc which includes a 1 Vdc safety margin.

5.11.6 Attenuation

FF operates at a frequency of 39 kHz where a standard FF cable has an attenuation of 3 dB/Km at 39 kHz or about 70% of the original signal after 1 Km.

A Fieldbus ‘transmitter’ can have a signal as low as 0.75 volts peak-to-peak and a Fieldbus ‘receiver’ must be able to detect a signal as little as 0.15 volts peak-to-peak.

Based on a 3 dB/Km attenuation, the Fieldbus signals can be attenuated by 14 dB. This normally does not provide a problem for Fieldbus installation especially based on the cable limits detailed above.

5.11.7 Grounding of Screens

All Fieldbus signal cores shall be preserved differentially throughout the network, as grounding either conductor would cause all FF devices on that segment to lose communications for the period that the conductor is grounded.

The instrument screen/shield shall be terminated at the host (power conditioner) end of the segment in the marshalling cabinet and shall not be connected to ground at any other place.

5.11.8 Segment Design Validation Tool

Within INtools all of the above segment wide parameters shall be entered with the required default and/or maximum values specified within this procedure.

In order to minimise the Fieldbus implementation effort, the Contractor shall be responsible to only change these default values when the actual device parameters/values exceeds these default values, i.e. by exception only.

However, the ‘calculated’ length for all trunk/homerun cables shall be specified as is the case for a traditional implementation.

Segment design validation shall be carried out by running the INtools Segment Validation Report that require no additional effort by the Contractor other than running the report.





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However, any ‘failed’ statuses on these reports shall be investigated by the Contractor and shall be brought to the attention of JPMT/ IOCL.

5.11.9 Junction Box Requirements

A Fieldbus junction box shall be adequately sized to contain two Fieldbus segments each with 10 off spur connections (see section 5.11).

The Fieldbus junction box shall follow the same principle and standards as for traditional junction box and shall include 2 rows of ‘Termination Blocks’, one for each segment.

Each ‘Termination Block’ shall be specifically made for FF networks with the following minimum requirements:

• 1 dedicated connections for the Fieldbus homerun / trunk cable

• 10 dedicated connection for each spur cable

• Built-in Fieldbus Terminator

• Dedicated grounding termination points will be provided to ground the individual cable screens for each cable (trunk and spur)

• Spring Clamp Terminals for all termination points

• Integral short circuit protection for spur connections*

• Current limiting to a maximum of 40mA per spur*

• Spur LED indicator to indicate when a spur is shorted/over current mode

• Bus power LED to indicate when bus power is available

• CENELEC approved EEx (n); or Zone 2, IIB, IIC

• Wire capacity: 0.5mm2 to 1.5mm2

• Temperature range –45 to +70°C

• DIN rail mounting

*Segment protector: To avoid breakdown of a segment in case of short on the spur or field device, the wiring block shall support short circuit protection (Spur Guard or similar).

6 INTOOLS REQUIREMENTS

INtools provides the ability to design and maintain the Fieldbus system of a plant, starting with the creation of Fieldbus tag numbers in the Instrument Index module, generation of instrument data sheets in the Instrument Specifications module and the generation of segment maps and other deliverables at the end of the process.

The Segment Manager provides for the creation and management of Fieldbus segments, association of instruments with the appropriate segments and the creation and management of virtual tags (multi-process variable instruments).





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The Fieldbus feature in the Wiring module is used to create the required Fieldbus cables (home-runs and spurs), manage the termination accessories and various apparatus types and create the required strips or junction boxes.

At the end of the process, segment I/O maps and Fieldbus SmartLoop drawings can be generated.

6.1 INtools Parameters Configuration 6.1.1 Segment-Wide Parameter Profile

The segment-wide parameter profile defines sets of defaults that serve as design rules for Fieldbus segments. INtools validates the design according to these parameters.

The following parameters shall be defined as defaults for INtools Fieldbus segments:

Table 5.1.1 (1) - Physical Limits and Bandwidth Defaults

Maximum Number of Devices per Maximum Number of Assigned Function Blocks per

Spur Segment IS Segment I/O Card Segment

1 10 6 -- 16

Table 5.1.1 (2) - Power Limits

Electrical Parameters

Power Supply

Allowable Current per non

IS Segment

Allowable Current per IS

segment

Minimum Receiver Voltage (V p-t-p)

Maximum capacitance

26 V 350 mA 80 mA 1 V 165 nF





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Table 5.1.1 (3) - Cabling Limits

Spur Cable Lengths (Meters)

Number of Devices per Spur Number of Devices per Segment 1 2 3 4

1-10 75 m (*) (*) (*)

(*) Not applicable - only 1 device per Spur shall be used.

6.1.2 Fieldbus Instrument Type Profiles

No additional instrument type profiles for Fieldbus instruments are required. Fieldbus instruments shall be created based on the traditional instrument type profile. Upon creation of the Fieldbus tag, by identifying the I/O type as Fieldbus, the instrument will inherit the Fieldbus properties.

6.1.3 Cable Parameters

A successful Fieldbus validation is dependant on the cable parameters, such as capacitance, resistance, length and attenuation of cable. INtools provides the facility to define default properties for each Fieldbus cable type.

The following parameters shall be defined as defaults for INtools Fieldbus cable type:

Table 5.1.3 – Default Fieldbus Cable Type

Cable Type Parameters

Cable Type Maximum Fieldbus length

m

Attenuation Factor db/km

Capacitance Factor pF/m

Cable Resistance

Ohm/km

Home-run & Spurs

1500 3 150 22

Spurs 750 3 150 22

However, Contractor shall ensure the project cable specification shall meet the above properties.

6.1.4 Termination Blocks

INtools provides the facility of creating Fieldbus termination blocks, such as the Relcom Fieldbus connection system. This facility enables one to generate a predefined configuration in order to create new Fieldbus termination blocks.

For this project, the 10-drop Fieldbus Termination Block with an internal terminator shall be used, see section 5.11.9.





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6.2 Fieldbus Tag Numbers 6.2.1 Adding New Fieldbus Tag Numbers

New Fieldbus instruments are added exactly the same as creating new tag numbers in the Instrument Index module. The instrument type profiles are the same for Fieldbus instruments as those for traditional instruments.

Once an instrument type has been defined for the new tag number and the system I/O as been defined as Fieldbus, the instrument will automatically acquire all the appropriate properties that have been set for that tag number.

Figure 5.2.1 – Fieldbus Tag Number Properties

Fieldbus Tag Number Properties

Fieldbus tag name Not required – use instrument TAG

Field device address Required – Defined by TAG

Device ID Required

Standard Foundation Fieldbus

DC consumption 30 mA

Capacitance 5 nF

Minimum transmission level (V p-t-p) 1 V

Operating Voltage 10 Vdc minimum (9 to 32 Vdc)

6.2.2 Associating Function Blocks to Fieldbus Instrument

INtools provides a set of most common function blocks whose properties are defined by the Fieldbus Foundation. These function blocks cannot be deleted or renamed, but their definitions can be modified if needed. User-defined function blocks can also be created and can be modified or deleted as required.

Function blocks are associated with a particular instrument type. This association will then enable the creation of new tag numbers that will automatically be associated with that particular function block.

6.2.3 Virtual Tags

Virtual tags are signals created internally in field devices. These signals can be secondary process measured variables that are measured by the same physical instrument where these signals originated. After assigning a tag number to a segment, add the required virtual tags to an instrument that has been associated with a function block. If this association does not exist for a particular tag number, no virtual tag can be created.





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6.2.4 Associating tags to specification sheets

Tags can be associated to Fieldbus specification sheets in the same way as non Fieldbus tags are associated to specification sheets. The Fieldbus specification form contains the regular specifications sheet with an additional page containing the Fieldbus requirements for that particular instrument.

6.3 Fieldbus Segments The Fieldbus Segment Manager provides for the creation and management of Fieldbus segments, association of instruments with the appropriate segments and the creation and management of virtual tags (multi-process variable instruments). You can also display and print out the detailed wiring of a segment.

6.3.1 Creating Fieldbus Segments

When creating new segments, the segments are associated to the required segment-wide parameter profile. Segments are defined as intrinsically safe or non-intrinsically safe.

INtools warns if any instruments currently associated with an intrinsically safe segment are not intrinsically safe and any instruments currently associated with a non-intrinsically safe segment are intrinsically safe.

6.3.2 Associating Tags to Segments

Once the segment has been created, instruments can be associated with the segment.

A Fieldbus instrument can be associated only with one Fieldbus segment. However, you can associate multiple tag numbers with one Fieldbus segment.

The segment association of an instrument can be changed, if needed. Before making a new segment association, the instrument will have to be disassociated from its current segment.

6.3.3 Fieldbus Segment Naming Convention

Refer to (HOLD).

6.4 Fieldbus Wiring The Fieldbus features in the wiring module of INtools enable the installation of a Fieldbus network wiring and attachment of the Fieldbus control devices.

6.4.1 Home-Run/Trunk Cables

INtools differentiates home-run cables from regular cables, as home-run cables propagate and connect the individual device spurs to the DCS. INtools provides the facility of defining cables as home-run, enabling then these cables to be associated to segments.





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6.4.2 Junction Boxes

Termination Blocks are added to junction boxes by creating the terminal blocks based on the configured termination blocks. Where internal terminators are used, ensure that the internal terminator check box has been selected.

6.4.3 Segment Wiring Drawings

Once the Fieldbus network connection is complete, segment wiring drawings can be generated.

6.5 INtools Fieldbus Validation INtools validates Fieldbus segments according to basic connection rules and according to parameters set for a given segment:

6.5.1 On-the-Fly Connection Validations

Upon attempting to connect, the software verifies that:

• An instrument to be connected is not associated with another segment.

• A home-run cable to be connected is not already connected to another segment.

• You are not trying to connect a non-Fieldbus instrument to a Fieldbus segment.

• You are not associating or wiring a non-intrinsically-safe instrument to an intrinsically safe segment. In this case, INtools will warn, but allow.

6.5.2 Segment-Report Validations

Other validations are performed by running a report from the Fieldbus Segment Manager. INtools reports a failed validation in the following cases:

• There are Fieldbus tags that are associated with a segment but not wired

• There are Fieldbus tags that have wiring, but are not yet connected to a segment

• There is a connection discontinuity between the field and a DCS or an I/O terminal strip

• The number of instruments in a segment exceeds the maximum specified for that segment

• The number of devices on a given spur exceeds the segment-wide parameter profile

• A spur length is exceeds the maximum set for that spur

• Total cable length exceeds the maximum you defined for the segment profile

• There are no terminators or less than two terminators in a segment

• Actual voltage at instrument terminals is below the minimum operating voltage





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• Total segment current consumption exceeds the maximum specified value

• Total capacitance exceeds segment maximum specified capacitance

6.5.3 Validation Requirements

In order for the Fieldbus validation to be performed successfully, the following should be taken into account:

• To define a cable type that supports Fieldbus validation, make sure that in the Cable Type Properties dialog box, you enter the required values for capacitance, capacitance UOM (unit of measure), cable resistance, cable resistance UOM, length UOM, and maximum Fieldbus length.

• To define an instrument tag that supports Fieldbus validation, make sure that in the Tag Number dialog box you enter valid information under Fieldbus Tag Number Properties.

INtools validation supports basic Fieldbus networks consisting of a single segment with no parallel branches and no repeaters.

6.6 Diagnostics On-line and off-line diagnostics shall be provided to assist in system maintenance and troubleshooting. Diagnostics shall be provided for every major system component and peripheral. This shall include segment as well as device diagnostics and firmware diagnostics in the devices. If diagnostics do not exist for particular peripheral devices (for example printers and terminals,) the system must detect and provide an error indication for the failure of these devices.

In case of Foundation Fieldbus transmitters all the diagnostic functionalities shall be integral part of DCS without the need for a separate sub-system, i.e. diagnostic functionalities as indicated for AMS should be an integral part of DCS functionalities in case of Foundation Fieldbus field transmitters.

It shall be possible to configure, monitor, and troubleshoot Foundation Fieldbus devices from the DCS. The DCS shall be capable of storing calibration information and device status history for each field device. It shall also be possible for the DCS to upload field device configuration changes implemented in the field. Once the configuration information is stored in the DCS, it shall be possible to download it to any other similar device, whether a new or replacement device. Diagnostic software shall be as per IEC 61804 for Foundation Fieldbus interoperabilities.

6.7 Testing Vendor shall develop a separate written test plan and test procedure for the FOUNDATION Fieldbus FAT.

6.7.1 Test Requirements





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Factory acceptance test shall be per the DCS specification with the following additions for FOUNDATION Fieldbus:

A complete functional test shall be conducted for one of each FF device used on this project (i.e. third-party and F-R products). This test will include, but is not limited to, plug-and-play interconnectivity to Host system; verify access to all device function blocks, and actual device operation, (i.e. simulate process inputs for transmitters, etc.).

The test shall include a calibration and setup for each type of FF device. Examples are changing RTD sensor types, calibrating transmitter span, zeroing P & DP transmitters, zeroing elevation on DP level transmitters. The intent of this requirement is to verify the ease of access to calibration wizards and setup procedures via the Host system.

All calibration and setup procedures, for each device, shall be documented in detail by the Vendor and approved by PMC/Owner

Vendor shall develop a redundancy fail-over test procedure for the H1 interface cards and Fieldbus power supplies. The test shall verify that automatic fail over shall not cause an upset, (i.e. I/O signal bumps, loss of operator view, mode changes, etc.). All H1 interface cards and FFPS shall be tested.

Each segment (port), including spares, shall be operationally tested by live connection of at least one Fieldbus device. The Fieldbus device shall be connected to the terminal block designated for the field wiring or system cable.

The FAT/IFAT procedure should be submitted to PMC/IOCL for approval one month before commencement of FAT/IFAT.

6.8 Device Maintenance When Fieldbus devices require replacement, it must be possible to accomplish this replacement within the following parameters:

All other devices on the Fieldbus segment continue to operate and report data to the Control System

No engineering access to the Control System is necessary

The system shall auto-sense a properly configured replacement device based on the device tag. This shall be sufficient for the Control System to complete any further tasks automatically, however the device blocks will be placed out of service.

The operator responsible for the device (based on the control strategy that is part of) shall be notified that the device is on-line and ready to be placed back into service.

Vendor shall offer the services of the installation team which would install the equipment in the control room, lay the interconnecting cabling inside the control room, check out, test and commission the system.





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6.9 Workstations Engineering Workstations Software and Hardware

Predictive Maintenance Management System shall be integrated into the engineering workstation to provide predictive maintenance like valve diagnostic and assist in commissioning activities like trim and calibration management. Minimally this module should be capable of diagnosing on-line device health monitoring and alert generation, with event capture and logging capabilities of all connected intelligent field elements. Vendor shall furnish details of functionality along with quotation/ offer.

Event module which provides ability to capture and log both operator and control system events with time and date stamping. Minimally the event types this module should capture include; operator initiated changes, alarm activity (e.g., initial active, acknowledged but active, and clear), configuration changes, controller downloads, control system device status changes (e.g., device “good-to-bad” status change, device “bad-to-good” status change), and intelligent field device status change (e.g., device “good-to-bad” status change, device “bad-to-good” status change).

Engineering module which provides a pre-configured library of process control objects to assist in developing application specific Distributed Control System solutions. The engineering module shall be capable of conducting both on-line and off-line control system applications. Minimally this module should be capable of developing full-function graphic displays, development of complex control strategies, sequences, and reports.

6.10 Alarm and Message Handling Process Alarm Initiation

To minimize analogue input "chattering" (a point going in and out of an alarm condition rapidly) there shall be configurable dead band parameters, on an individual tag basis.

For analogue tags, the configurable triggers for process alarms shall include:

• Process variable high limit exceeded

• Process variable high high limit exceeded

• Process variable low limit exceeded

• Process variable low low limit exceeded

• Process variable rate-of-change high

• Process variable deviation from setpoint

• Process variable invalid value

For digital tags, the configurable triggers for process alarms shall include:

• Either state





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• Change of state.

A list of inhibited alarms shall be available to be displayed and printed.

System Alarm Initiation

All devices connected to the DCS communication network shall be monitored for failures. A system alarm shall be generated for each failure detected.

Process and System Alarms History Retention

All alarms shall be stored in history files with the capability to archive these to removable media. Capability shall be provided to recall these alarms in visible display lists and printed lists according to selectable filtering options.

Process and System Alarms Audible Annunciation

All alarms for a process area may be assigned to any workstation at configuration time. All alarms shall be displayed on the workstation(s) designated. The audible alarm shall be user configurable for different tones or patterns. The system shall have an adjustable volume control. The system shall use global alarm acknowledgement allowing a single acknowledgement from any workstation to acknowledge that alarm on all workstations and to silence the audible alarm.

Process and System Alarms Visible Annunciation

Alarms shall cause visible display annunciation at, and only at, a Workstation configured for those alarms. The annunciation shall occur within 3 seconds of detecting the initiating event. It shall be possible to acknowledge process alarms only from a Workstation configured for those alarms. It shall be possible for an operator to acknowledge any alarm configured at his Workstation by no more than two actions. An alarm shall be acknowledgeable only if it is shown on a visible display.

7 DOCUMENTATION REQUIREMENTS

Documentation requirement for FF system design is the same as for a traditional system with the following additional documents/drawings:

• Segment Validation Report

• Segment Drawing





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INtools supports both the above documents as standard features and as such, no additional effort is required by the Contractor other than running the reports from INtools.





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Appendix-A

8 FIELDBUS SYSTEM DESIGN GUIDELINES

8.1 General Foundation Fieldbus is an all-digital, serial, two-way communication protocol that interconnects devices in the field such as sensors, actuators, and controllers. Foundation Fieldbus has also the capability to distribute control applications across its network in the field. Furthermore it enables advanced diagnostics and asset management tools resulting in higher plant availability. A typical Fieldbus installation provides connection from a network of field devices to a host system via a two way, serial communication link. The cabling and connections are arranged in a multi-drop fashion, requiring only a single pair wire with parallel connections to field devices. This is quite different from the traditional approach of connecting 4 to 20 mA devices to a DCS system using dedicated pairs of wires for each device.

Fig. 8.1.1 (1) shows the traditional dedicated pair approach. Fig.8.1.1 (2) shows a typical Fieldbus arrangement.

Fig. 8.1 (1): Traditional Approach to Instrument Connection

P

T

L

F





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Fig. 8.1 (2): Typical Fieldbus Approach to Instrument Connection

Two-way, multi-drop, digital

P

T

L

F Each Fieldbus run from the host system to the field is known as a segment. Each segment consists of a trunk or home-run running from the host system (DCS) and out through the processing plant with parallel connected spurs linking to field devices such as transmitters and control valves. Junction boxes are preferred to connect the trunk to the individual spurs.

A power supply connected to the trunk provides conditioned power to all devices on the Fieldbus segment.

8.2 Main Differences between Fieldbus & Traditional Installation 8.2.1 Hardware

The difference in cabling is one of the beneficial features of Fieldbus technology. In FF the power and communication is provided over the same cable with some exceptions such as Magflow meters.

In addition, as a result of the network configuration there are less I/O cards, I/O interface racks and marshalling cabinets required both in CCR’s and in the SRR’s.

Also more sensors can be integrated in one FF device leading to a reduction in field devices and/or enhanced diagnostic features.

8.2.2 Communication

FF technology is tag driven, which means that the host will check and commission devices on basis of tags in the database and with the auto addressing of devices, a reduction in the loop check effort can be realised.

The data transfer is fully digital which eliminates the need for re-ranging and re-calibration because of drift.

Furthermore a higher accuracy in process control can lead to less variability and less product give away.





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8.2.3 Protocol

The FF protocol enables the adequate transfer of all sorts of messages such as, Process Variable, status, diagnostics, etc. This coupled with the ability of the host to convert all these basic data into information leads to higher plant availability and reduced maintenance costs.

However, there is a need for well-trained and qualified personnel to handle the technology changes and exploit all the advantages.

8.2.4 Engineering

The Fieldbus system design process itself is similar to the traditional system design. However, for traditional systems the device layouts and cable schedules are used mainly for marshalling cabinet design, and the DCS system will be designed based on I/O lists and process operation procedures, irrespective of the cable schedule or the location of the devices and junction box.

Whereas, in case of a Fieldbus based system, the field side details, i.e. segment design, do affect the DCS system design. This means that the DCS system design is dependant on device layout, cable detail, i.e. segment design details.





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Fig. 8.2 Main Difference between Traditional and Fieldbus System

Fieldbus System 1) 2 way Digital Communication Communication Cycle LAS Allocation Cable Spec & Cable Length 2) Multi-Drop Cable Connection Device Grouping Wiring Topology JB Configuration & Location Power Supply for Multi Devices No Marshalling Function in MDF 3) Function Block in Device & DCS Basic Function Block Advanced Function Block Multi-vendors Devices

Redundant Fieldbus Interface

Fieldbus JB

FF devices

Fieldbus Cable (2 Pair)

Redundant PS/Conditioner

Terminator

CONT

MARSHALLING CABINET

Conventional I/O System

1) Analogue (4 - 20mA) 2) 1 :1 Cable Connection 3) Function Block in DCSCONT

Local JB

Multi-Core Cable Conventional

Type Field Devices

MARSHALLING CABINET

CONT

I/O

8.2.5 Example Calculation

To aid understanding the following example considers cable length, voltage drop, and power consumptions:





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Spur Cable(1) 22 ohm/Km (2) Length: 75 m per Spur (3) Total: 750 m (10 devices x 75m)

FieldbusJunction Box

PSU

10 FF devices (30mA / device at 10 V)

Total 24Vdc

Voltage Drop 2 = Total Power = 0.03A x (22 ohm/1000m) x (75 m x 2 wires)

0 1 Vd

Trunk Cable(1) 22 ohm/Km (2) Length 750 m

Voltage Drop 1 = Total Power in Trunk x Resistance= 0.3 x (22 ohm/1000m) x (750 m x 2 wires)= 9.9 Vdc

Total Required Voltage= Voltage Drop 1 + Voltage Drop 2 + Min Device Voltage + 1Vdc Signal= 9.9 + 0.1 + 10 + 1= 21 Vdc = 21 Vdc < 24 Vdc of PSU

Figure 8.13.9 Example Calculation

Power Consumption = 0.03 x 10 devices = 0.3 Amps

Segment Power =0.3 < 0.35 Amps of PSU

3210-8550-fs-0008 foundation fieldbus functional requrement

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