ff in hazardous area[1]

8/8/2019 Ff in Hazardous Area[1]

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1 Fieldbus Foundation Norway Stavanger 2008

FOUNDATIONTM Fieldbus inHazardous Areas

Physical Layer Concept

Einar S. Huse

NOREX / MTL


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FF Basic Information

FIELD

CONTROL ROOM

FF Power Supply

Fieldbus controlsystem (DCS)

Trunk

Spur

Min. 9VMin. 10mA

Typical 12-16devices.

Tx @ 14 mAPos @ 22mA

31,25 Kbit/s32 Address

12 dev. @ 1s scan

Field wiring hubw. Short circuit protect.


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FF Basic Information


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Fieldbus in hazardous areas

Bulk power

Hazardous area

?

Hazardous Areaprotection?

FOUNDATION Fieldbus Devices

FIELD

CONTROL ROOM

Field Wiring

Hub

Whatapprovalsfor wiringhub andjunction

box?

What

approvalsfor Fieldbusdevices?

Specialprotectionfor fieldbus

power

supply?



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Methods of protection

Method of protection Zone 2 Zone 1

Ex d field devices and Ex ejunction boxes

Ex i/Intrinsically SafeENTITY or FISCO

Exe Exi/Fieldbus Barrier

Ex nL / FNICO

Ex nA, Non-Arcing


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Ex-d /Ex-e Fieldbus

Ex-eField Wiring

Hub

Bulk power

Hazardous areaFOUNDATION Fieldbus Devices

FIELD

CONTROL ROOM

Ex-d / Ex-eInstruments


Ordinary Safe Area Power SupplySingle or Redundant

No livemaintenance!


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Entity Intrinsically Safe Fieldbus

ENTITYcertified

devices!

Bulk power

Hazardous areaFOUNDATION Fieldbus Devices

FIELD

CONTROL ROOM

Field Wiring

Hub Max 4Fieldbudevices!


IS Fieldbus power supplyTypical 80mA output

For all Ui Uo

For all Ii Io

All Pi Po

Ci + Cc Co

Li + Lc Lo


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Introducing FISCO Fieldbus Intrinsically Safe Concept, IEC 60079-27

Provides more current to IS trunk than earlier Entitymodel, and hence more field instruments

Proven by tests performed at PTB

Simplifies design and installation

Reduces documentation

First simplification of explosion protection techniques formany years!

3000 50 100 150 200 250

273mA

215mA

280mA

PowerSupply

Supply with cable

Supply with cableand Terminators

Ignition current in mA(including Safety Factor)Source: Dr. Ulrich Johannsmeyer, PTB


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All instruments FISCO certified

Power Supply must be FISCO certified

Field cables must conform to the followingspecification:

loop resistance must be between 15 and 150ohms/km loop inductance must be between 0.4 and 1mH/km

loop capacitance must be between 45 and 200nF/km

maximum length of each spur cable is 60m in IIC and IIB

maximum length of each trunk cable is 1km in IIC or 5km inIIB

The limits are not restrictive

typical Fieldbus cable has parameters of 50ohms/km,0.8mH/km and 120nF/km

FISCO requirements


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FISCO installation

FISCO power supply(IIB / IIC)

FIELD

CONTROL ROOM

Intrinsically SafeField wiring hub

Intrinsically safe FISCO Fieldbus devices

Zone 1Division 1

24Vdc24Vdc


LiveMaintenance

!

LiveMaintenance

!


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Multiple hazardous area trunks


Zone 1Division 1

24Vdc24Vdc

Trunk #2 Trunk #3

Directparallel

connectionon safe

area side


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Redundant FISCO architecture

Redundant FISCOpower supply

FIELDZone 1

CONTROL ROOM

24Vdc24VdcBulk power input


Intrinsically Safe

Field wiring hub

IntrinsicallySafe trunkand spurs


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More field devices with FISCO

Entity, IIC/IIB Gas Groups

FISCO, IIC Gas Groups

FISCO, IIB Gas Groups

80mA available, typically3 - 4 devices

120mA available, (140mA)typically 6-8 devices

265mA available,(280 mA)typically 14-16 devices

Zone 1Division 1


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FB Fieldbus Barriers: Exe/Exi concept

Galvanic isolation and IS barrier in the field.

Ex-e trunk with higher current available

Zone-1 mountable fieldbus wiring hub for Intrinsically safe fieldbusdevices

Supports FISCO and Entity field devices


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Fieldbus Barrier

FIELD

CONTROL ROOM

Intrinsically safe Fieldbus Devices

Increased safety(Ex e) trunk

Fieldbus control system

IS spurs

FieldbusBarriers

Power supplySingel or RedundantUp to 8 channel

modules available


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Fieldbus Barrier across Zones

HOST / LAS

PowerSupply

POWERSUPPLIES


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Comparision of Protection Techniquesused in

Hazardous Area


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Entity IS vs. FISCO

Entity IS FISCO

Intrinsically safe trunk andspurs?

Live-working permitted in anypart of field network?

Simple safety documentation?

Eliminate cable parametercalculations?

Gas Group IIB option?

Max output current 80mA 265mA

Max spur length 120m 60m


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FISCO vs. Fieldbus Barrier

FISCO Fieldbus

Barrier

IS Spur? Live Maintenance?

IS Trunk? Live Maintenance?

Simple documentation?

Redundant Power

Redundant Field Wiring Hub

Compatible with FISCO fielddevices?

Compatible with Entity fielddevices?

Only with spur

connector!


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Introducing FNICO

Fieldbus Non-Incendive Concept For fieldbus in Zone 2 and Division 2 hazardous

areas

Complete field network is Non-Incendive EEx nL

Live-workable throughout without gas clearance,

just like Intrinsic Safety Based on FISCO, the Fieldbus Intrinsically Safe

Concept

Easy to install, easy to document, easy to maintain.


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Key benefits of FNICO

Wide choice of suitable field devices: IS Entity certified

FISCO certified

Ex nL certified

Relaxed installation rules Dont need to comply with IS segregation rules

FNICO cables can share cable trunking with non-IScircuits

More available current than FISCO inIIC/Group A: FISCO: 120mA

FNICO: 180mA


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Typical FNICO installation

FNICO power supply

Ex n or IntrinsicallySafe Field wiringhub

Non-incendive or Intrinsically safe Fieldbus devices

Division 2Zone 2

24Vdc24Vdc

FIELD

CONTROL ROOM

Live-workableNon-incendivetrunk and spurs

Live-workableNon-incendivetrunk and spurs


Also hasrepeater

function formultipletrunks


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How many field devices?FISCO / FNICO

Entity, IIC/IIB Gas Groups

FISCO, IIC Gas Groups

FISCO, IIB Gas Groups

80mA available, typically 3 - 4 devices

120mA available, typically 6-8devices

265mA available,typically 14-16devices

FNICO, IIB Gas Groups320mA available, typically 18-20devicesZone 2/Division 2

Assumes 17mA per

field device

Zone 1/Division 1


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FF Installation Advices


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Surge protection for fieldbus

Host

DIN rail mount Fieldbussurge protector for thepower supply, host andFieldbus Barrier

Threaded entryFieldbus surge

protector for fieldinstrument

Recommended surge:

If >100m between devices

OR >10m vertically

Fieldbus installations are more vulnerable to surge damage

than conventional point-to-point wiring


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Fieldbus Maintenance and Diagnosis

Diagnostic modules

Fieldbus testers

Devices on net

# transmissions

# failed transmissions

Retransmisson rate

Average noise in diff.bandwidth

Peak noise in diff.bandwidth

Voltage level of all devices

Signal level of all devices

Short Circuit of all dev.


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How to connectNon FF

Field Devices to FF?


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Digital IO and Temperatur Mux

8 DI / 4 DO (low power)

ATEX certified zone 1 & 2

8 ch Temp. Multiplekser

RTD and THC


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FF Remote IO

Remote IO for Zone1

IO modules for Exi and Exe


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Field Mounting

Panel Mounting

FF Displays

1 Address on the net

FISCO compliant

ATEX certified zone 1 & 2

Non-Hazardous area


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FF Structure Example


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Typical Cabinet Layout

32 segments per cabinet side: 24 segments per cabinet side:

with bulk power supply


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In summary... FISCO - IS solution for Zone 1

Intrinsically safe wiring: safe maintenance New IEC standard (60079-27: 2005)

Fieldbus Barrier - High power Trunk Zone 1 More field devices per segment in IIC gases

Compatible with FISCO and ENTITY

FNICO delivers FISCO benefits in Zone 2

Advanced Diagnosis available

Many ways to include non-FF signals

Dont forget surge protection! REMEMBER GROUNDING!


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Thank you!

ff in hazardous area[1]

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