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Fieldbus Accessing all Areas 1 Fieldbus Accessing all Areas 1

Fieldbus Scope of presentation Safe Area Applications Non-Arcing Systems Zone 2 Non-Incendive Systems Zone Fieldbus Scope of presentation Safe Area Applications Non-Arcing Systems Zone 2 Non-Incendive Systems Zone 2 FNICO Intrinsic Safety Systems FISCO 2 Zone 2, 1, 0

Fieldbus Generalised Fieldbus connection Non-hazardous area Hub T T Fieldbus Host 18 -30 volt Fieldbus Generalised Fieldbus connection Non-hazardous area Hub T T Fieldbus Host 18 -30 volt Power 3 l General fieldbus application in safe area l terminated at both ends of bus

Fieldbus Generalised Fieldbus connection Non-hazardous area Hub T T Fieldbus Host 18 -30 volt Fieldbus Generalised Fieldbus connection Non-hazardous area Hub T T Fieldbus Host 18 -30 volt Power l Need for hazardous area protection l suitable certified interface applied Non-hazardous area Hazardous area T 4 T T T Fieldbus Host

Fieldbus MTL 5995 Power Supply l For general purpose applications in 31. 25 kbit/s Fieldbus MTL 5995 Power Supply l For general purpose applications in 31. 25 kbit/s fieldbus systems l terminate at both ends of fieldbus l switched internal terminator option l Isolated power conditioning l 19 V, 350 m. A output l Suitable for Safe Area & Hazardous Area applications l Certified for installation in Zone 2 hazardous areas l Needs suitable certified interface eg, MTL 791, for intrinsically safe field connection 5 ATEX II 3 G EEx n A IIC T 4

Fieldbus Redundant Fieldbus Power System l Backplane connects to : bus terminator input power Fieldbus Redundant Fieldbus Power System l Backplane connects to : bus terminator input power supplies host system fieldbus trunk alarm circuitry l Load sharing by redundant supplies l Up to 8 units may be daisy-chained l with common alarm l carrier jumper supplied l l l version without segment terminator available 6

Fieldbus 7 Redundant Fieldbus Power System l Power Conditioning l high impedance to fieldbus Fieldbus 7 Redundant Fieldbus Power System l Power Conditioning l high impedance to fieldbus network l Redundant DC Power Inputs l Power Isolation to fieldbus l 250 V ac galvanic isolation l Redundant Output Power l 25 Volt, 350 m. A output per module l LED indicates bus is powered l Hot-swappable l modules & / or input supply can be replaced without affecting fieldbus operation l Alarm Circuitry l input power or unit failure l galvanic isolation from other functions l Certification l FM Class 1 Div 2 l ATEX II 3 G EEx n. A IIC T 4 l Zone 2 Mounting Fieldbus Host T System Alarm Supply ‘A’ Supply ‘B’ 18 -30 volt Power Fieldbus

Fieldbus Redundant Fieldbus Power System Common connections within addressing limitations Fieldbus Host System Alarm Fieldbus Redundant Fieldbus Power System Common connections within addressing limitations Fieldbus Host System Alarm Fieldbus Host T T Fieldbus Supply ‘A’ Supply ‘B’ 18 -30 volt Power 8

Fieldbus Redundant Fieldbus Power System l Note : l the fieldbus connection is certified Fieldbus Redundant Fieldbus Power System l Note : l the fieldbus connection is certified as non-arcing EEx n. A IIC T 4 l It is NOT a FISCO / FNICO field connection l an added interface would be necessary to achieve this end 9

Fieldbus MTL 5053 Isolator / Power Supply l The MTL 5053 extends 31. 25 Fieldbus MTL 5053 Isolator / Power Supply l The MTL 5053 extends 31. 25 kbit/s fieldbus networks into hazardous areas l Provides power to the highway & for communication to field devices l Separate power may be required for safe-area field devices l Supply voltage 20 to 35 Vdc l Isolation : 250 V ac between l safe area fieldbus circuits l hazardous area fieldbus circuits l power supply l Provides 18. 4 volts at max 80 m. A l Safety description 22 V, 102 , 216 m. A l Isolator transparent to fieldbus, hence 31. 25 kbit/s fieldbus termination at isolator is not a pre-requisite l Switchable safe area terminator Hazardous area Ex II (1) GD [EEx ia] IIC 10 Safe area MTL 5053 T T

Fieldbus Some definitions Safe area Zone 2 Division 2 Safe Area system NA system Fieldbus Some definitions Safe area Zone 2 Division 2 Safe Area system NA system NI system Non-Arcing Systems Non-Incendive Systems 12 Zone 1 Zone 0 Division 1

Fieldbus The principle of live working Limit the energy in the circuit Ethylene group Fieldbus The principle of live working Limit the energy in the circuit Ethylene group Propane group Current Methane group Hydrogen group Power = volts x amps Resistive Curves 13 Voltage

Fieldbus Safety Factor Unity : Zone 2 1. 5 : Intrinsic Safety Fault-tolerant components Fieldbus Safety Factor Unity : Zone 2 1. 5 : Intrinsic Safety Fault-tolerant components not required for Zone 2 Hydrogen group Current 230 m. A Apply a Safety Factor 14 Resistive Curves 24 Volts Voltage

Fieldbus Types of circuit in Zone 2 NON-INCENDIVE CIRCUITS : NON-ARCING CIRCUITS : Energy-limited Fieldbus Types of circuit in Zone 2 NON-INCENDIVE CIRCUITS : NON-ARCING CIRCUITS : Energy-limited • Unity Safety Factor • Low energy circuits • Systems concept • Live-workable • High energy & mains circuits • No systems concept • Not live-workable n User must NOT permit arcing 15

Fieldbus Complete hazardous area capability Safe area Unclassified location Safe Area system NA system Fieldbus Complete hazardous area capability Safe area Unclassified location Safe Area system NA system NI system IS system Zone 0 system 16 Zone 2 Division 2 Zone 1 Zone 0 Division 1

Fieldbus Safe Area or Non Arcing Installation l Installation in => IP 54 l Fieldbus Safe Area or Non Arcing Installation l Installation in => IP 54 l Live working NOT permitted in a hazardous area ‘n. A’ l Max output : l 32 V l 1. 5 A l All trunks & spurs l EEx n. A IIC T 4 l Vmax 32 V l Imax 1. 5 A l MTL 5995 l FPS-I ‘n. A’ l System Certification : l Ex n. A IIC T 4 l Class 1, Div 2, Groups A, B, C, D, T 4 17 l Terminator : FBT-1 l Vmax 32 V l FF-816 specification : l 32 V l 1. 5 A

Fieldbus Non Incendive / ‘Spurguard’ legs l Installation in => IP 54 l Live Fieldbus Non Incendive / ‘Spurguard’ legs l Installation in => IP 54 l Live working NOT permitted on ‘n. A’ trunk ‘n. A’ ‘n. L’ l Main trunks : l EEx n. AL IIC T 4 l Vmax 32 V l Imax 1. 5 A l Spurguard legs : l EEx n. L IIC T 4 l Vmax 32 V l Imax 60 m. A ‘n. A’ ‘n. L’ l Max output : l 32 V l 1. 5 A l MTL 5995 l FPS-I l Live working safe on ‘NI’ spurs l System Certification : l Ex n. A [n. L] IIC T 4 l Class 1, Div 2, Groups A, B, C, D, T 4 18 l Terminator : l Vmax 32 V l FF-816 specification : l 32 V l 1. 5 A

Fieldbus Non Incendive System l Installation in => IP 54 l Live working permitted Fieldbus Non Incendive System l Installation in => IP 54 l Live working permitted throughout ‘n. L’ l MTL 9111 l Max output : l 14 V l 233 m. A l All trunks & spurs l EEx n. L IIC T 4 l Vmax 14 V l Imax 233 m. A ‘n. L’ l MTL 9112 ‘n. L’ l System Certification : l Ex n. L IIC T 4 l Class 1, Div 2, Groups A, B, C, D, T 4 19 l Terminator : l Vmax 32 V option for IIB with appropriate safety parameters

Fieldbus Non Incendive >> ‘Spurguard’ legs l Installation in => IP 54 l Live Fieldbus Non Incendive >> ‘Spurguard’ legs l Installation in => IP 54 l Live working permitted throughout ‘n. L’ l All trunks & spurs l EEx n. L IIC T 4 l Vmax 14 V l Imax 233 m. A l Spurguard legs l EEx n. L IIC T 4 l Vmax 14 V l Imax 60 m. A ‘n. L’ l MTL 9112 ‘n. L’ l System Certification : l Ex n. L IIC T 4 l Class 1, Div 2, Groups A, B, C, D, T 4 20 l MTL 9111 l Max output : l 14 V l 233 m. A l Terminator : l Vmax 32 V option for IIB with appropriate safety parameters

Fieldbus Intrinsically Safe (Non-FISCO) Installation l Installation in => IP 54 l Live working Fieldbus Intrinsically Safe (Non-FISCO) Installation l Installation in => IP 54 l Live working permitted throughout ‘IS’ into Zone 0 l MTL 5053 l Available output : l 18. 4 V 80 m. A l Safety parameters : l 22 V 216 m. A ‘IS’ l System Certification : l Ex ia IIC T 4 l Class 1, Div 1, Groups A, B, C, D, T 4 21 l Terminator : l Vmax 24 V l Imax 250 m. A l FF-816 specification : l 24 V l 250 m. A

FISCO 22 Fieldbus FISCO 22 Fieldbus

Fieldbus Intrinsically Safe (FISCO) Installation l Installation in => IP 54 ‘IS’ l Megablock Fieldbus Intrinsically Safe (FISCO) Installation l Installation in => IP 54 ‘IS’ l Megablock rating : l Vmax 14. 8 V l Imax 380 m. A ‘IS’ 23 l Live working permitted throughout l MTL 9121 IS : IIC l 14. 0 V l 180 m. A l MTL 9122 IS : IIB l 14. 8 V l 380 m. A l System Certification : l Ex ib IIC T 4 l Class 1, Div 1, Groups A, B, C, D, T 4 l Use in appropriate gas group l Terminator : l Vmax 24 V l Imax 250 m. A l Limited to Zone 2 & 1 l All devices to be approved for FISCO

Fieldbus Network Calculations 24 Fieldbus Network Calculations 24

Fieldbus Multiple power supply configuration l Sufficient current capacity ? T T 25 Host Fieldbus Multiple power supply configuration l Sufficient current capacity ? T T 25 Host T T

Fieldbus Basic configuration Host L N E 9121 & 9122 T 24 V supply Fieldbus Basic configuration Host L N E 9121 & 9122 T 24 V supply Host trunk 2 - 3+ 4 - 5 S 6+ T T 7+ 8 S 9 - Safe Area Zone 1 / Div 1 Hazardous Area 6 devices (120 m. A) in IIC 13 devices (260 m. A) in IIB if 20 m. A consumption each device 26 T

Fieldbus Power & data Host L N E T 24 V supply 2 - Fieldbus Power & data Host L N E T 24 V supply 2 - 3+ 4 - 6+ T T 7+ 8 S 9 - Safe Area Zone 1 / Div 1 Hazardous Area l The Fieldbus l The 24 volt 27 power supply is converted to an intrinsically safe supply to feed the IS trunk T signal, which is superimposed on the IS voltage, is fed via the interface device to & from the field devices

Fieldbus Mains or 24 -volt power supply 8913 8914 Power Units Zone 2 / Fieldbus Mains or 24 -volt power supply 8913 8914 Power Units Zone 2 / Div 2 Host Power consumption 9121 : 190 m. A 9122 : 300 m. A Mains 5991 Power Unit 8914 : 10 A 5991 : 2 A T Mains 28 Safe Area T T T

Fieldbus Design Parameters l System design determined from : l power supply output voltage Fieldbus Design Parameters l System design determined from : l power supply output voltage l power supply available current l knowledge of current consumption of each field device l survey shows a range of 10 to 28 m. A l 20 m. A is assumed l application of Ohm’s Law to the cable network l assessment for adequate voltage at each field device l Line resistance of 50 /km is assumed l within the FISCO range of 15 to 150 /km Model Apparatus Number Class 9121 -IS 9122 -IS 29 IIC IIB Useable Output V m. A 12 120 12. 8 260 Parameter Value Loop resistance 15 ohm to 150 ohm / km Loop inductance 0. 4 m. H to 1 m. H / km Capacitance 80 n. F to 200 n. F / km Spurs are in addition to permitted maximum cable length FISCO cable parameters

Fieldbus Model 9121 -IS : IIC 5 connected field devices at end of trunk Fieldbus Model 9121 -IS : IIC 5 connected field devices at end of trunk Eg : I = 100 m. A 600 metres 30 = 3 volts 30 m spur = 1. 5 carrying 20 m. A volt drop = 30 m. V 31 Hydrogen Gas Group Typical IIC calculation 600 metre IS trunk Useable Output V m. A 12 120 12 volts 600 metre IS trunk 3 volts 100 m. A If current drawn < 20 m. A then instrument population can be increased 9 volts NODE T each instrument draws 20 m. A

Fieldbus Typical IIC calculation I = 80 m. A 12. 5 = 1. 0 Fieldbus Typical IIC calculation I = 80 m. A 12. 5 = 1. 0 volt I = 40 m. A 12. 5 = 0. 50 volts 32 Model 9121 -IS : IIC 5 distributed field devices I = 100 m. A 12. 5 = 1. 25 volts 750 metre IS trunk Hydrogen Gas Group 12 volts 250 metres 10. 75 V 250 metres 9. 25 V T Useable Output V m. A 12 120 each instrument draws 20 m. A

Fieldbus Typical IIB calculation 12 connected field devices at end of trunk I = Fieldbus Typical IIB calculation 12 connected field devices at end of trunk I = 240 m. A = 3. 8 volts drop thru 316 metres of 15. 8 Ethylene Gas Group Model 9122 -IS : IIB 12. 8 volts Useable Output V m. A 12. 8 260 316 metres 316 metre max IS trunk 33 3. 8 volts 240 m. A Trunk length will increase if device population is reduced 9 volts NODE T 12 instruments each drawing 20 m. A

Fieldbus Power Supply as a IIB Repeater Safe Area Zone 2 / Div 2 Fieldbus Power Supply as a IIB Repeater Safe Area Zone 2 / Div 2 Zone 1 / Div 1 316 metres 24 volts Power & Ex protection only Power, Repeater & Ex protection 1. 8 kms 12 instruments 316 metres Power drawn in either direction Cable protection required 34 24 volts A similar scenario exists for a IIC repeater

Fieldbus Power Supply as a Repeater Safe Area l l Zone 2 / Div Fieldbus Power Supply as a Repeater Safe Area l l Zone 2 / Div 2 Host probably has no Ex protection in powering the 912 x device : l Cable is a non-arcing circuit due to incendive level of energy l Cable protection required - hazardous area wiring may not be disconnected to reveal floating wires l Repeater terminals carry limited energy; hence circuit is non-incendive and power plug may be removed 912 x device may power host equipment (max 30 m. A) and power plug may be removed Power, Repeater & Ex protection 1. 8 kms Power drawn in either direction 35 Zone 1 / Div 1

Fieldbus ATEX Certification The ‘CE’ Mark Confirms compliance with all relevant Community directives Conformite Fieldbus ATEX Certification The ‘CE’ Mark Confirms compliance with all relevant Community directives Conformite European 38 ex The ‘Explosive Atmosphere’ Mark Confirms compliance with ATEX or previous Flammable Atmosphere Directive

Fieldbus Equipment Marking - 9121 Power Supply CENELEC / IEC [E Ex ib] IIC Fieldbus Equipment Marking - 9121 Power Supply CENELEC / IEC [E Ex ib] IIC T 4 -40 OC < Tamb < +70 OC Referenced to ambient of -20 to +40 OC unless indicated as above u Temperature Class (Group II) u Apparatus Group (Hydrogen) u Type of protection code u Explosion protection symbol u Conformity with European Standard 39 T 1 : 450 OC T 2 : 300 OC T 3 : 200 OC T 4 : 135 OC T 5 : 100 OC T 6 : 85 OC

Fieldbus Equipment Marking - 9121 Power Supply CENELEC / IEC [E Ex ib] IIC Fieldbus Equipment Marking - 9121 Power Supply CENELEC / IEC [E Ex ib] IIC T 4 -40 OC < Tamb < +70 OC [ ] indicates the apparatus is safe area mounted ‘associated apparatus’ suitable for connection to Ex ib equipment Referenced to ambient of -20 to +40 OC unless indicated as above u Temperature Class (Group II) u Apparatus Group (Hydrogen) u Type of protection code u Explosion protection symbol u Conformity with European Standard 40 T 1 : 450 OC T 2 : 300 OC T 3 : 200 OC T 4 : 135 OC T 5 : 100 OC T 6 : 85 OC

Fieldbus Equipment Marking - 9121 Power Supply ATEX II (2) GD 0600 G : Fieldbus Equipment Marking - 9121 Power Supply ATEX II (2) GD 0600 G : Gas, vapour, mist D : Dust u Type of explosive atmosphere (Group II) u Equipment Category u Equipment Group M 1 : energised M 2 : de-energised 1 : Zone 0, 20 2 : Zone 1, 21 3 : Zone 2, 22 I : Mining II : Non-Mining u EU Explosive Atmosphere Symbol u Ref to Notified Body responsible for testing 41 u CE mark

Fieldbus 9121 - BASEEFA Certification 0600 II (2) GD ATEX [E Ex ib] IIC Fieldbus 9121 - BASEEFA Certification 0600 II (2) GD ATEX [E Ex ib] IIC T 4 -40 OC < Tamb < +70 OC CENELEC / IEC BAS 02 ATEX 7276 EC-type examination certificate ATEX Category 2 certification 42 u Additional information on product : Safety parameters, where applicable Year of manufacture & Serial No. Name & address of manufacturer Manufacturers type identification

Fieldbus 9121 - MTL Declaration of Conformity II 3 GD ATEX E Ex n. Fieldbus 9121 - MTL Declaration of Conformity II 3 GD ATEX E Ex n. A IIC T 4 -40 OC < Tamb < +70 OC CENELEC / IEC MTL 02 ATEX 9121 X MTL Declaration of Conformity ATEX Category 3 certification justifying mounting the 9121 power supply in Zone 2 43 9121 X refers to special conditions of use : > power supply is installed in an appropriate enclosure > it must be protected from large supply transients

Fieldbus 9122 - BASEEFA Certification 0600 II (2) GD ATEX [E Ex ib] IIB Fieldbus 9122 - BASEEFA Certification 0600 II (2) GD ATEX [E Ex ib] IIB T 4 -40 OC < Tamb < +70 OC CENELEC / IEC BAS 02 ATEX 7277 EC-type examination certificate ATEX Category 2 certification 44

Fieldbus 9122 - MTL Declaration of Conformity II 3 GD ATEX E Ex n. Fieldbus 9122 - MTL Declaration of Conformity II 3 GD ATEX E Ex n. A IIB T 4 -40 OC < Tamb < +70 OC CENELEC / IEC MTL 02 ATEX 9122 X MTL Declaration of Conformity ATEX Category 3 certification justifying mounting the 9122 power supply in Zone 2 45

Fieldbus Intrinsically Safe Concept (FISCO) l Adopting FISCO raises the issue : l Can Fieldbus Intrinsically Safe Concept (FISCO) l Adopting FISCO raises the issue : l Can Entity certified fieldbus equipment (non-FISCO) be incorporated into a FISCO network ? YES 47 9321 -SC 9323 -SC

Fieldbus I. S. Entity Spur Connections (non-FISCO devices) 9121 -IS : IIC 9321 -SC Fieldbus I. S. Entity Spur Connections (non-FISCO devices) 9121 -IS : IIC 9321 -SC Entity spur connector output safety parameters : 14 V; 180 m. A; 2. 52 W deliver 12. 0 V; 110 m. A EEx ib IIC T 4 II 2 (2) G Live working throughout 9321 -SC Zone 1 Entity IS certified device 48 Entity device to FF-816 has an input safety description of 24 V; 250 m. A; 1. 2 watts HUB T FISCO devices

Fieldbus Intrinsically Safe Concept (FISCO) l The use of active current limitation restricts the Fieldbus Intrinsically Safe Concept (FISCO) l The use of active current limitation restricts the categorisation to ‘EEx ib’, ie, connection to Zone 1 only l Can a fieldbus device be installed in a Zone 0 by adding further protection to achieve ‘ia’ status ? YES 50 9322 -SC

Fieldbus Networking into Zone 0 9322 -SC Zone 0 spur connector Useable with either Fieldbus Networking into Zone 0 9322 -SC Zone 0 spur connector Useable with either 9121 -IS : IIC 9122 -IS : IIB II 2 (1) G EEx ib IIC T 4 II (1) G EEx [ia] IIC 9322 -SC Zone 1 ia : Zone 0 energy limit Zone 0 51 NODE T FISCO devices

Fieldbus Wiring Components 52 Fieldbus Wiring Components 52

Fieldbus Wiring Components - Megablock Series l Megablocks : l DIN-rail mounting Fieldbus network Fieldbus Wiring Components - Megablock Series l Megablocks : l DIN-rail mounting Fieldbus network hubs l connect multiple field devices to trunk network l minimise hand wiring l network integrity maintained during connection / disconnection of individual devices l LED indicates minimum 9 volts present at hub l Megablocks available in 2, 4 & 8 -way (10 -way) versions l Megablock terminator available Terminator l Short-circuit protection option using Spur. Guard 53

Fieldbus Megablock Series Trunk / Home run Field device connection Power LED >= 9 Fieldbus Megablock Series Trunk / Home run Field device connection Power LED >= 9 V Optional Spur. Guard short circuit protection - visual indication of fault Trunk / Home run Securable, pluggable connectors 54 8 -way Megablock

Fieldbus Megablock Series Choice of junction box Use site standard suitable for environment trunk Fieldbus Megablock Series Choice of junction box Use site standard suitable for environment trunk 4 + 8 drop = 12 drop l Easy to retrofit l Junction box for specific application l standard instrument cable spur 55 terminator

Fieldbus Relcom Spur. Guards™ l System reliability and availability may be affected l by Fieldbus Relcom Spur. Guards™ l System reliability and availability may be affected l by the shorting of the fieldbus highway, l by the failure of any individual fieldbus device, l thus interrupting data communication across the entire bus segment l could occur during installation or routine instrument maintenance l A Spur. Guard™ is a current-limiting device that provides short circuit protection to the fieldbus segment l By attaching a Spur. Guard™ at each point where a field device is attached to the segment home run cable, isolation of the network from individual device failures is achieved l Spur. Guards™ are available with any Megablock l a red LED indicates when a Spur. Guard™ is providing overcurrent protection l Because a Spur. Guard™ leg draws power from the 56 segment when in short circuit mode, their short circuit current consumption must be taken into account during segment design l The Spur. Guard™ short-circuit current is nominally 60 m. A l Trunk to Spur max. voltage drop = 0. 4 volts

57 Fieldbus 57 Fieldbus

Fieldbus Lightning Strikes Handling the effect 58 Fieldbus Lightning Strikes Handling the effect 58

Fieldbus Lightning Strikes l There is no remedy for direct lightning strikes l the Fieldbus Lightning Strikes l There is no remedy for direct lightning strikes l the energies involved are too high l but measures can be taken to minimize the effects of near-lightning strikes on Fieldbus networks l Lightning is a short burst of very intense voltage and current. l Even when a direct lightning strike is shunted to ground by a lightning rod, it induces high voltages and currents in metal components nearby eg, the conductors & shield of Fieldbus cable l The purpose of lightning surge protection 59 in Fieldbus wiring is to minimize the induced voltages & currents and hence to minimise damage to Fieldbus equipment l a lightning strike might produce 100, 000 Amps in a lightning rod l induced currents in nearby grounded metal objects may be several thousand Amps l induced current in the shield of a fieldbus cable might be several hundred Amps I PK (100 k. A) 90% 50% 10% 8µs 20µs t

Fieldbus Principles & Practicalities Flash-over 100 k. A Local Ground Strike Flash-over Fieldbus High Fieldbus Principles & Practicalities Flash-over 100 k. A Local Ground Strike Flash-over Fieldbus High local potential on building earth system 60 Induced Voltage V = L x I/ t Local ‘ground’ High potential across insulation on field instrument

Fieldbus Transient Surge Suppression l The shield of the Fieldbus cable is grounded l Fieldbus Transient Surge Suppression l The shield of the Fieldbus cable is grounded l but according to the installation standard, in only one place l Single-point grounding eliminates current loops in the shield l reduces induced noise in the signal concerned l is a pre-requisite for an intrinsically safe circuit l the shield is normally grounded at the control room l Any lightning strike in the field could produce a large current in the shield that needs to travel to the control room to pass to ground l in a long network a large shield voltage could occur l by capacitive coupling a large voltage might appear on the internal twisted pair l A surge may be minimized by using a Transient Surge Suppressor Centralised control equipment Shield Transient Surge Suppressor 61

Fieldbus Differential Voltage Suppression l The next consideration is to minimize the voltage that Fieldbus Differential Voltage Suppression l The next consideration is to minimize the voltage that might be induced in the twisted-pair inside the shield l Due to the capacitance between the shield & each of the wires in the twisted pair, l a voltage change on the shield will induce a voltage on the wires l Using twisted-pair cable, the shield-to-wire capacitances for the two wires are nearly equal l hence the voltage induced in each of the wires in the twisted pair will be identical (Common Mode Voltage effect) l The Fieldbus standard requires that the common mode immunity of Fieldbus devices should be of a high order, eg, Surge Protection Devices : l FP 32 = 225 volts DC trigger point l TP 32 = 120 volts DC trigger point 62

Fieldbus Protection Devices l The FP 32 surge protection device prevents surges & transient Fieldbus Protection Devices l The FP 32 surge protection device prevents surges & transient overvoltages conducted along the Trunk or Spurs of fieldbus systems from damaging the associated electronics l may be used at any point on a Trunk to safely divert any surges to ground l The TP 32 is the protection equivalent installed at an instrument l Fully automatic in operation, the devices react instantly to make sure that equipment is never exposed to damaging surges between lines or between lines & earth l Reacting instantaneously to surges they then reset automatically FP 32 63 TP 32

Fieldbus Surge Protection Device Line inductors Circuit fuses Signal lines Protected equipment Gas discharge Fieldbus Surge Protection Device Line inductors Circuit fuses Signal lines Protected equipment Gas discharge tube Circuit earth Solid-state limiters I PK (100 k. A) 90% l The multi-stage elements of the FP 32 / TP 32 use a combination of solid state electronics 64 and a gas filled discharge tube (GDT) to provide surge protection up to 20 k. A 50% 10% t 20µs

Fieldbus Power problems due to transient spikes Surge < 10% Sag < 10% Transient Fieldbus Power problems due to transient spikes Surge < 10% Sag < 10% Transient 85% to 90% 65 Outage < 1%

Fieldbus Generalised Fieldbus connection Power conditioner Hub T Terminator Trunk T Power supply Power Fieldbus Generalised Fieldbus connection Power conditioner Hub T Terminator Trunk T Power supply Power distribution panel Incoming AC supply 66

Fieldbus Host System protection Hub T Terminator Power conditioner FP 32 T Trunk Power Fieldbus Host System protection Hub T Terminator Power conditioner FP 32 T Trunk Power supply MA 4000 Power distribution panel Incoming AC supply 67

Fieldbus Field Device Protection - ‘compact’ Hub FP 32 T Trunk Terminator Spurs < Fieldbus Field Device Protection - ‘compact’ Hub FP 32 T Trunk Terminator Spurs < 50 m horizontal < 10 m vertical l All spurs less than : l 50 m horizontal or l 10 m vertical l Surge invasion from host end of trunk l all devices are protected by one surge protection device in trunk 68

Fieldbus Field Device Protection - ‘widespread’ Hub FP 32 T Trunk Terminator Spurs > Fieldbus Field Device Protection - ‘widespread’ Hub FP 32 T Trunk Terminator Spurs > 50 m horizontal > 10 m vertical l Spurs greater than : l 50 m horizontal or l 10 m vertical 69 l surge invasion from Host end of trunk l surge protection installed to each device

70 Fieldbus 70 Fieldbus