MTL FFieldbus HA solutions and Diagnostics.pdf

Cooper Industries/MTL Confidential

Foundation Fieldbus H1 Introduction

Taking fieldbus H1 into Hazardous Areas


How is fieldbus different from 4-20mA?

4-20mA

Power

Supply

fieldbus

PowerSupply

– In a Fieldbus system, the power supply, field devices and input card are connected in parallel.

– In 4-20mA circuits, the power supply, field device and input card are connected in series.

Input card


Expanded System View

FCS: Expanded view. Field

devices are part of the system.

DCS: Limited system view. Does

not include diagnostics and other

information from field devices.

15.3 mA

TAG = LIC-012

VALUE = 70.34

UNITS = m3

STATUS = GOOD

ALARM = Y/N


Advantages of fieldbus over 4-20mA

Measurement accuracy• Process variable is converted to digital value in the field

device

• Value cannot be corrupted by leakage or electrical interference

• Allows „tighter‟ control of process

Better diagnostic information• Field device diagnostics result in maintenance savings

• No „in range‟ errors

Fewer wire terminations

Cable savings• Multicore „home run‟ cable replaced by single twisted pair


IEC 61158 Physical Layer

standard

31.25kb/s

Up to 32 devices per

segment - depends on

several factors

Shielded twisted pair - can

use existing field wiring

Power down the bus

Up to 1900 metres with best

cable - more with repeaters

Intrinsically safe

Device connection

Physical Layer - specifications


Fieldbus in hazardous areas

FIELD

CONTROL ROOM

24Vdc

Control system

FOUNDATION Fieldbus Devices

Wiring

Hub

Trunk

Terminator

Integrated terminator

Power supply & conditioner

(FFPS)

Spur

SEGMENT


+

-

9-32V100 W

1 mF

SignalIsolationInductors

Near-EndTerminator

100 W

1 mF

Far-EndTerminator

Field Devices

1,900m max.

Power Conditioner

Fieldbus Electrical Circuit Diagram

Power supply, H1 interface card,

field devices and terminators are all

connected in parallel

H1

Interface


Fieldbus needs terminators

Terminators are required, one at each end, to:

• Provide matched line impedance to minimise reflections &

distortions, and

• Define the impedance of the bus for conversion from current

modulation to voltage modulation*

No more than 2 terminators may be used on one

segment

* FF devices transmit by modulating the current and receive by detecting the modulated voltage

T 100W

1mF

Fieldbus

Host

Control

System

D

T


Wiring topologies

Point-to-Point

Trunk

Bus with Spurs

Trunk

Daisy-ChainTrunk

“Chicken Foot”

or Tree

JBTrunk

Preferred


Selection of Power Supplies and

Wiring Components



Fieldbus in hazardous areas

FIELD

CONTROL ROOM

24Vdc

Control system

Hazardous areaFOUNDATION Fieldbus Devices

Wiring

Hub

Trunk

Terminator

Integrated terminator

Power supply & conditioner

(FFPS)

Spur

?

Hazardous Area

protection

Hazardous Area

protection

?


Methods of protection

Method of protection Zone 2 Division 2

Zone 1 Division 1

FISCO – Intrinsically Safe

Fieldbus barrier

Ex d/Explosionproof

Ex e/Increased safety

FNICO

Ex nA Non-Arcing

Ex n/Non-incendive

Ex nL

Energy-Limited


Hazardous area protection

Two End user groups:

• Use intrinsic safety or non-incendive field wiring

• allows live working without gas clearance certificate

• eg. Aramco, BP, Bayer, Chevron, Mol, ONGC

• Use Ex d/explosionproof or non-arcing

• gas clearance certificate required for live working

• eg. Shell, Exxon Mobil


Live working of field devices

High Energy Trunk

Energy Limited

Trunk

Features No limit on number of devices

Redundant power Limitations on live

working

Limit number of devices

Simplex power Live work trunk and

spurs

Zone 2/Division 2 Non-incendive spurs FNICO

Zone 1 Fieldbus barrier

Zone 22/21 Fieldbus barrier

Division 1 Fieldbus barrier*

FISCO

* Fieldbus barrier is

located in Division 2


FIELD

CONTROL ROOM

Live-workable Ex nL

spurs

Control system

Ex nL or Intrinsically Safe Fieldbus devices

Zone 2

Division 2

General purpose

Fieldbus power supply

High Energy Ex nA trunk

Spur short-circuit

protection in wiring

hub makes spurs

Ex nL

Non-arcing trunk with Non-incendive spurs

24Vdc24Vdc


Non-incendive spurs

Field instruments may carry any of the following

approvals:

• Intrinsically safe

• Non-incendive (North America)

• EEx nL (IEC)

Compliance with the following parameters is

required:

• Ui > or = fieldbus power supply max voltage

Recommend Ui > or = 32V

If Ui = 24V use F801 module

If Ui > or = 30V use F802 module


FIELD

CONTROL ROOM

Ex nA spurs

Control system

Ex n or Ex d/Explosionproof Fieldbus devices

Zone 2

Division 2

High energy Ex nA trunk

Non-arcing trunk and spurs

No live working without power-down

or gas clearance

Fieldbus power

supply

24Vdc24Vdc


Ex d field devices in Division 1

CONTROL ROOMCONTROL ROOM

Control system

FIELD

Spurs not live-workable

Ex d/explosionproof Fieldbus devices

Zone 1

Division1

High energy Trunk

not live-workable

Junction box:

Ex d/Explosionproof

or Ex e

Fieldbus power

supply24Vdc24Vdc


Ex e/d field devices in Zone 1

CONTROL ROOMCONTROL ROOM

Control system

FIELD

Spurs not live-workable

Ex d/explosionproof Fieldbus devices Zone 1

Trunk not

live-workable

Junction box:

Ex d/Explosionproof

or Ex e

Field wiring hub

EEx me approved

Fieldbus power

supply

24Vdc24Vdc


FNICO power supply

FIELD

CONTROL ROOM

Live-workable Ex nL

spurs

Control system

Ex nL or Intrinsically Safe Fieldbus devices

Zone 2

Division 2

24Vdc24Vdc

Live-workable Ex nL trunk

Typical FNICO installation


FISCO power supply

FIELD

CONTROL ROOM

Live-workable

Ex i spurs

Control system

FISCO fieldbus devices

24Vdc24Vdc

Live-

workable

Ex i trunk

Zone 1

Division 1

GAS DUST

Zone 21

Typical FISCO installation

MTL Redundant FISCO.ppt


Multi-drop capability

Intrinsically safe FISCO Fieldbus devices

Zone 1

Division 1

24Vdc24Vdc

Trunk #2 Trunk #3

Direct

parallel

connection

on safe

area side


FISCO for hazardous area applications

Intrinsic Safety preferred by many end users for protection of

instrumentation in hazardous areas

• Recognised as „Safest possible technique‟

• Maintenance personnel don‟t need re-training on non-IS techniques

• Field enclosure smaller, lighter and less complex than alternative

techniques using simple wiring hub

Simple safety documentation compared with earlier IS Fieldbus techniques

• Cable parameter calculations –associated with conventional IS circuits – are not needed

Trunk cable lengths and segment loading adequate for many

applications

• Typically 8 devices with 830m trunk cable length in IIB gases

• Typically 5 devices with >640m trunk cable length in IIC gases

Multi-drop capability


Fieldbus Barrier

Control system

High energy

Ex e trunk

Fieldbus

barrier

Fieldbus power

supply

24Vdc24Vdc

FIELD

CONTROL ROOM

Zone 1

Division 2

GAS DUST

Zone 1/0

Division 1

Zone 21

Zone 21/20

FISCO or entity fieldbus devices

Live-workable

Ex i spurs


„High Energy Trunk‟ for hazardous areas

25

Benefits of High Energy Trunk concept:

Redundant Fieldbus power supply can be used

Typically 12 instruments (typically limited by cycle time)

Fieldbus trunk is not energy-limited, so very long segment lengths

can be supported

Spurs connect to FISCO or Entity instruments; simple verification

of intrinsic safety

Disadvantages of existing Fieldbus Barrier implementations:

Enclosure involves many components

Solution is customized

Field enclosure is large, complex, expensive

Mix of protection methods within main enclosure compartment

(Ex e trunk and Ex ia spurs) risks maintenance errors


Maintenance-friendly High-Power

Trunk



Legacy fieldbus barrier

Designed to provide high levels of energy

in to the field by:

• Using high-power FFPS

• Moving the IS interface into the hazardous area

One Ex e trunk connection per module

Enclosure needs extra terminals for:

• Trunk separation to further barrier modules

• Field device connection


Legacy Fieldbus barrier

Live-workable

Ex i spurs

Control system

FISCO or entity fieldbus devices

High energy

Ex e trunk

Fieldbus

barrier

Fieldbus power

supply

24Vdc24Vdc

FIELD

CONTROL ROOM

Zone 1

Division 2

GAS DUST

Zone 1/0

Division 1

Zone 21

Zone 21/20


Custom-designed to suit

project requirements:

• Enclosure material

• Ex-protected isolating switch

option

• Fixed terminator options

• Trunk and spur surge

protection options

• Internal cable management

• Field wiring terminal options

Ex protected

isolating switch

option

Spur surge

protector

option

Additional terminalsTrunk surge protection

and optional combined

fieldbus terminator

Customised FBB enclosure

Cooper Industries/MTL Confidential 30

Connections in customised systems

Number of terminals:

Spur: + / - / Shield of FBB to + / - / Shield of Surge Protector. There are 12 spurs = 72

Spur: + / - / Shield of Surge Protector to + / - / Shield of screw terminal. There are 12 spurs = 72

Trunk: + / - / Shield of FBB to + / - of Ex de switch. There are 3 Trunks = 15

Trunk: + / - of Ex de switch to + / - / Shield of Ex e terminals. There are 3 Trunks = 15

Total = 72 + 72 + 15 + 15 = 174 terminals = 174 potential points of failure!


12-spur SS enclosure

“Live

pluggable”6-spur Fieldbus

Barrier modules

Spur surge

protector

(optional)

“Live

pluggable”

Terminator

Trunk

terminals

“Live pluggable”

trunk surge

protector

(optional)

Trunk

Terminal

Assembly

(TTA)

housing

Screw-

secured,

pluggable

spur

terminals


6-spur GRP enclosure

“Live

pluggable”

6-spur Fieldbus

Barrier modules

Spur surge

protector

(optional)

“Live

pluggable”

Terminator

Trunk

terminals

“Live pluggable”

trunk surge

protector

(optional)

Trunk

Terminal

Assembly

(TTA)

housing


9373-FB Series Fieldbus Barrier enclosure (12 spur)

FIELD

Zone 1

CONTROL ROOM

Increased safety (Ex e)

„High Energy‟ trunk

Fieldbus

Barrier

enclosure

General Purpose

Fieldbus Power

Supply

Intrinsically

Safe spurs

Fieldbus control

system (DCS)

24V dc Bulk power input

Intrinsically safe FISCO or Entity Fieldbus Devices


Compare size with legacy 12-spur solutions

Existing 12-spur solutions with Surge Protection

9373-FB 12-spur

Fieldbus Barrier

with Spur Surge

Protection

All images approx. to scale


MTL’s 9370-FB is up to 50% smaller than conventional Fieldbus Barrier implementations, leading to significant savings in infrastructure and installation costs

Replace this...

Surely not!

950mm

430mm

.....with this

430mm


But size doesn‟t matter!

All system components

are pluggable, even in the

hazardous area:

• Safer, easier maintenance

• Allows expansion from 6

to 12 spurs per enclosure*

• Install trunk and/or spur

surge protection modules

during initial installation

or as retro-fit

• Faster fault diagnosis by

substitution

36

Fieldbus Barrier

module

Spur surge

protectors

(one per spur)

Trunk surge

protector

Fieldbus

terminator

* Specify 9374-FB (12-spur) enclosure with 6 spurs

fitted; expand to 12-spurs by addition of second

9377-FB module


Module carrier

Supplied as part of complete enclosure

assembly

6-spur and 12-spur versions

Provides mechanical and electrical

mounting platform for 9377-FB Fieldbus

Barrier module(s)

Provides pluggable connections to fieldbus

spurs

Robust design

Supports optional Spur Surge Protection

modules

• Integrated high integrity ground connection

37


How are the modules „hot pluggable‟?

Ex de plug/socket system

Patented technology from Cooper Crouse-Hinds

Integrated part of:

• Fieldbus Trunk Terminator

• Trunk Surge Protector

• Fieldbus Barrier Module

Gas tight when inserting (Ex d)

Mechanically designed for Ex e

Allows removal of equipment without

gas clearance or additional Ex de switches

Plug

Socket


Simplified maintenance

Maintenance

activity

Conventional Fieldbus Barrier

enclosure

9370-FB Series

Fieldbus Barrier

enclosure

Remove and

replace

Fieldbus

Barrier module

• Remove enclosure cover

• Select and operate appropriate

isolating switch

• Open trunk terminal cover on

barrier module

• Remove trunk wiring from

terminals and secure

• Remove spur wiring from

terminals and secure

• Remove and replace barrier

module

• Reinstate trunk and spur wiring

and close trunk terminal cover

• Operate isolating switch

• Replace enclosure cover

• Remove enclosure

cover

• Loosen module

screws

• Remove and replace

barrier module

• Tighten screws

• Replace enclosure

cover

39


Every module and circuit within the shaded area is live-

workable in the hazardous area

Reducing maintenance risk

Mixing circuits that can be live-disconnected in a hazardous area with those that can’t leads to unnecessary risks during field maintenance – which is

why all circuits and modules.

“I can open the enclosure door of the main compartment and so it only contains IS circuits doesn’t it?”


Every module and circuit within the shaded area is live-workable

in the hazardous area

Mixing circuits that can be live-disconnected in a hazardous area with those that can’t leads to unnecessary risks during field maintenance – which is

why all circuits and modules in the main enclosure compartment are designed to be replaced while powered.

Reducing maintenance risk

Non-live workable circuits are confined within the Trunk Terminal Assembly compartment and protected by a lockable cover.This only ever needs to be opened during installation and when the trunk cable fails and needs to be swapped over. On both occasions there is no power.


User-Friendly Handheld, Periodic

Diagnostics

Fieldbus H1 Physical Layer Diagnostics


Reliability of fieldbus physical layer

At commissioning a few installation

and device faults require correction

After commissioning fieldbus

segments run reliably

• on 300 segment system about one

physical layer problem needs

resolving/year

Relcom fieldbus testers are

estimated to be used on more than

90% of segments installed


Commissioning Procedure

inspect wiring

unplug power conditioner field

connector

• signal + to signal - >50kohm

• signal + to screen >20Mohm

• signal - to screen >20Mohm

• signal + to ground bar >20Mohm

• signal - ground bar >20Mohm

• screen to ground bar >20Mohm


Common Faults

Shorts (between +, -, shield, ground)• water

• stray wire strands

• cable damage, etc.

Intermittent connections• broken wires

• improperly connected shield

• loose connector/wire

Terminator• missing/extra/failed

• wrong location

Cable• non compliant

• water ingress

• routed near noisy cable/equipment

• too long

Component failure• Power supply

• Wiring component/terminator

• Field device

Power supply is not isolated


Characteristics of user-friendly diagnostics

Easy to measure

Easy to understand

Gives definite indication of a problem

Eliminates possible causes

Actionable


Fieldbus Diagnostic Measurements

Segment Voltage

• Measure voltage on segment

Low Frequency Noise

• Noise measurement at n Hz

In Band Frequency Noise

• Noise measurement at 31 kHz

High Frequency Noise

• Noise measurement at

400kHz

Peak Frequency Noise

• Maximum noise at each of

Low, In Band, and High

frequencies

Live Device Count

• Addition or removal of device

on network

Positive Short to Shield

• Short circuit between these 2

cables

Negative Short to Shield

• Short circuit between these 2

cables

Device Signal Level

• Voltage is between 0.35 and 1

volt

Retransmissions

• Number of messages that

need to be sent more than

once on the network

New Device

• Displayed for 1 hour

Device Removed

• Displayed for 1 hour


Diagnostics using the FBT-6

Basic failure

alarms

H1 Fieldbus

Plant Resource ManagerTM

(including fieldbus diagnostics)Host control system


system Field junction boxSegment 1 of 8

FBT-6 Hand-held

Diagnostic Module

I/O &

Controller


Commissioning Procedure

Connect fieldbus tester at each

field device and at rack room

Save data to FBT-6 memory

Upload fieldbus tester data to

PC via USB

Store segment baseline data


Typical faults found in commissioning

fieldbus shorts to cable screen due to

poor installation

• fieldbus cable strands shorting to cable shield



screen grounded at more than one

location when no plant equipotential

ground

• incorrect installation with screen grounded at

devices or in junction boxes

• poor installation practice with loose strands

intermittently connecting to ground

identify by inspection and measuring

groundbar to screen resistance



insufficiently tightened terminations

faults in physical layer components

• quality issue with batch of knife disconnects


Typical faults found in operation

water in junction box, cable or device



corroded terminals



fieldbus short to cable screen



electrical noise

• welding cables on fieldbus cable trays

• variable speed drives installed with inadequate

cable grounding



faulty fieldbus device


Periodic monitoring - pros & cons

Advantages

• Low cost

• No false alarms

• Monitor anywhere

Disadvantages

• Data collected manually

• Limited awareness of problems


User-Friendly Online, Continuous

Diagnostics

Fieldbus H1 Physical Layer Diagnostics


On-line monitoring

Monitor diagnostic parameters all the time

Diagnostic module attached to the

network

Reports parameters

• using separate bus infrastructure

• using fieldbus

Diagnostic software

• standalone

• integrated in system instrument

management software


Diagnostics using the FBT-6Diagnostics using the F809F

Basic failure

alarms

H1 Fieldbus

Instrument Management System

(including fieldbus diagnostics)Host control system


system Field junction boxSegment 1 of 8

FBT-6 Hand-held

Diagnostic Module

On-line

Diagnostic Module

I/O &

Controller


MTL F809F on-line monitoring

Monitors parameters on 8 fieldbus segments

Reports parameters over fieldbus• ie. It is a fieldbusTM H1 device

No Diagnostic software• Seamlessly integrated into

IMS as FF H1 device

Open solution

• FOUNDATION fieldbusTM H1

device easily integrates with

all DCS

• Full device description

support

F809F


F809F diagnostic module

Discrete input block

- any parameter in alarm

Resource block

segment transducer blocks

Fieldbus diagnostic

module


MTL F809F on-line monitoring

Future proof architecture

• Fieldbus DTM support

• Enhanced eDDL support

Minimises total cost of

ownership by integrating

into fieldbus H1 system

• No additional hardware costs

• No additional costs in

installing, commissioning

and maintenance of separate

network

• Instrumentation team use

same software for physical

layer and fieldbus device

diagnostics


F809F measured parameters

Segment voltage

Average and peak noise• Low frequency band

• FF signalling band

• High frequency band

Fieldbus to shield short circuits• +/- to shield

Device signal voltage• All devices

• Address of device having lowest voltage

Device retransmissions• Address of devices failing to respond to Pass Token

messages from LAS

Address of fieldbus device most recently connected

Number of devices recognised on bus

Address of LAS


F809F with Honeywell Experion PKS

Up to 10 discrete input blocks can be

configured

Resource block

8 segment transducer blocks

F809F device

systems transducer blocks


F809F in Yokogawa PRM

Segment noise

Device 1 quality


F809F in ABB 800xA

Power feed B

low voltage alarm

Power feed B

voltage 0.4V


F809F trending in Invensys

Trending of

fieldbus segment noise


Segment alarms in Emerson Delta V


Troubleshooting questions...

So what does the data all mean?

Is anyone capable of diagnosing the data provided?

What does the scope trace show us?

Does anybody know what jitter is and what it means?

Where do we look next?

Can anybody find the manual?

………?


Characteristics of user-friendly diagnostics

Easy to measure

Easy to understand

Gives definite indication of a problem

Eliminates possible causes

Actionable


User-friendly presentation

What we need is:

• Home view for status summary

• Technicians view for current values , alerts

and corrective actions

• Advanced configuration and set up view


Simple: Home Page

Diagnostic module is a

device on the Fieldbus

port

Home view gives overview about

system (FFPS) and all segments


Simple: Technicians View

75

Device shows out of

specification alarm.


Simple: Advanced User

76

The Config/Setup tab allows

to configure warning and

alarm limits for each device.


The Config/Setup tab

provides a wizard to

optimise alarm limits

Simple: Advanced User


Open standards: NAMUR NE107

FailureFunction Check

Out of Specification

Maintenance Required

Diagnostic Categories


Namur NE107

79

Device overview lists all devices

with tag and status.

Only 3 devices on segment, only

3 devices displayed.

Symbols and designations as per

FF-912 and NAMUR NE107.


Device is ok.

Device OK


Device shows needs

maintenance alarm.

Device needs maintenance


DTM Segment View


DTM Graphical View

Out of

Specification

Needs

maintenance

Good

Current

value


Enhanced EDDL

84

System TB block shows

data for power supply


System TB block config

allows to set limits for

fieldbus power supply

Enhanced EDDL


Select which segments

are monitored*

* Segments without field wiring (and hence without second terminator) would give alarm as terminator is missing.

Select segments to be monitored


EDDL can execute methods

(“wizards”)

Alarm optimisation wizard

sets alarms for users set up

FF Methods

Cooper Industries/MTL Confidential88

Device alarm help

Network diagnostic data: DTM

2009 General Assembly

Yokohama, Japan

Troubleshooting guide


Export Baseline


Segment Commissioning Report

Namur NE107

status symbols

Alert limitsCurrent values

Documents

MTL FFieldbus HA solutions and Diagnostics.pdf