Category: Eaton

Each intrinsically safe spur is capable of supporting a FISCO

or ‘Entity’ certified fieldbus device located in a Zone 0 or

1 hazardous area. The short-circuit protected spurs are

galvanically isolated from the trunk and require no protective

ground connection in the field.

Unlike conventional Fieldbus Barrier products that are

based on stand-alone modules, the 937x-FB2-Px range is

supplied as complete, factory-assembled systems in stainless

steel (SS) enclosures that do not require additional wiring,

customised housing or complex ancillary components.

Electrical and mechanical aspects of the design are integrated

for a ergonomic solution for ‘High Energy Trunk’ applications

in hazardous areas.

The key modular components of the system (Fieldbus

Barriers and Surge Protectors) may be ‘hot-plugged’ by

design and without gas-clearance procedures or separate

isolating switches. This virtually eliminates the risk

associated with hazardous area maintenance activities,

speeds module replacement and avoids the need for

specialist operator training.

Optional features include pluggable surge protection

components for the fieldbus trunk and individual spurs.

Connection facilities with generous room for cable

management are provided within the Fieldbus Barrier

enclosure for the trunk and spur wiring. Where appropriate,

the trunk wiring may be extended from one Fieldbus Barrier

enclosure to another.

Enclosure systems for 6 or 12 spurs are supported. For

added flexibility, the 12-spur enclosure can be specified part

populated with one 6-spur barrier module installed. This

permits future expansion from six to twelve spurs simply by

plugging in an additional module.

The 937x-FB2-PC-SS range of Fieldbus Barriers are bus

powered and requires no additional power supply in the field.

When used with a fieldbus host control system, power for the

trunk may be provided by MTL F800 or 9180 range of fieldbus

power supplies in redundant or non-redundant format.

• For FOUNDATION™ fieldbus networks in hazardous areas

• Complete enclosure system for 6 or 12 intrinsically safe spur connections

• Mount in Zone 1 (gas) or 21 (dust) with spurs connected into Zone 0

• Compatible with FISCO and Entity certified fieldbus instruments

• Compact, modular construction

• Ergonomic mechanical design

• Pluggable system components, without ‘gas free’ constraints

• Optional, integrated surge protection for trunk and spurs

The 937x-FB2-Px-SS range of Fieldbus Barriers are field

mounted wiring hubs that create up to twelve intrinsically safe

spur connections from a high-energy trunk, for connection

to suitably certified FOUNDATION™ fieldbus H1 instruments.

Capable of supporting heavily loaded fieldbus segments

and long trunk cable lengths, the Fieldbus Barriers may be

installed in Zone 1 (gas) or Zone 21 (dust) hazardous areas,

with the trunk wiring implemented using suitably protected

cable and increased safety (Ex e) connection facilities.

The 9372-FB redundant fieldbus barrier is based on our

revolutionary 9370-FB range of products, which are supplied

as complete, factory-assembled enclosure systems that do not

require additional wiring, customised housings or complex

ancillary components. Electrical and mechanical aspects of the

design are integrated, providing the industry’s first complete,

ergonomic solution for ‘High Energy Trunk’ applications in

hazardous areas.

Uniquely, the key modular components of the system (Fieldbus

Barrier, Terminator and Surge Protectors) may be ‘hot-plugged’

by design and without gas-clearance procedures or separate

isolating switches. This virtually eliminates the risk associated

with hazardous area maintenance activities, speeds module

replacement and avoids the need for specialist operator training.

Optional features include pluggable surge protection

components for the fieldbus trunk and individual spurs.

Connection facilities with generous room for cable management

are provided within the Fieldbus Barrier enclosure for the trunk

and spur wiring.

For added flexibility, a redundant-capable enclosure can be

specified part-populated with one 6-spur module (model

no. 9375-FB). This permits future upgrading from simplex to

redundant mode simply by plugging in an additional Fieldbus

Barrier module and optional alarm module.

The 9372-FB Fieldbus Barrier is bus powered and requires no

additional power supply in the field. When used with a fieldbus

host control system, power for the trunk may be provided by

redundant power supplies.

In common with conventional Fieldbus Barriers, each

intrinsically safe spur is capable of supporting a FISCO or ‘Entity’

certified fieldbus device located in a Zone 0 or 1

hazardous area. The short-circuit protected spurs are

galvanically isolated from the trunk and require no protective

ground connection in the field.

The 9372-FB redundant fieldbus barrier is based on our

revolutionary 9370-FB range of products, which are supplied

as complete, factory-assembled enclosure systems that do not

require additional wiring, customised housings or complex

ancillary components. Electrical and mechanical aspects of the

design are integrated, providing the industry’s first complete,

ergonomic solution for ‘High Energy Trunk’ applications in

hazardous areas.

Uniquely, the key modular components of the system (Fieldbus

Barrier, Terminator and Surge Protectors) may be ‘hot-plugged’

by design and without gas-clearance procedures or separate

isolating switches. This virtually eliminates the risk associated

with hazardous area maintenance activities, speeds module

replacement and avoids the need for specialist operator training.

Optional features include pluggable surge protection

components for the fieldbus trunk and individual spurs.

The 9372-FB may therefore be selected for critical process

applications where failure of the Fieldbus Barrier would

otherwise result in unacceptable downtime or lost production.

It is also ideal for use in Fieldbus Safety Instrumented Function

(SIF) networks in which nuisance trips cannot be tolerated.

Failure annunciation to the host control system is provided by

means of an integrated Foundation™ fieldbus device with Digital

Input Function Block capability.

In common with conventional Fieldbus Barriers, each

intrinsically safe spur is capable of supporting a FISCO or ‘Entity’

certified fieldbus device located in a Zone 0 or 1

hazardous area. The short-circuit protected spurs are

galvanically isolated from the trunk and require no protective

ground connection in the field.

The 9372-FB redundant fieldbus barrier is based on our

revolutionary 9370-FB range of products, which are supplied

as complete, factory-assembled enclosure systems that do not

require additional wiring, customised housings or complex

ancillary components. Electrical and mechanical aspects of the

design are integrated, providing the industry’s first complete,

ergonomic solution for ‘High Energy Trunk’ applications in

hazardous areas.

• For For Foundation™ fieldbus networks in hazardous areas

• Redundant configuration for super-high system availability

• Complete enclosure systems for up to 6 intrinsically safe spur connections

• Failure alarm direct to host control system via integrated fieldbus device

• Mount in Zone 1 (gas) or 21 (dust) with spurs connected into Zone 0

• Compatible with FISCO and Entity certified fieldbus instruments

• Ergonomic mechanical design

• Pluggable system components, without ‘gas free’ constraints

• Optional, integrated surge protection for trunk and spurs

The 9372-FB Redundant Fieldbus Barriers are field-mounted wiring

hubs that create up to six intrinsically safe spur connections

from a high-energy trunk, for connection to suitably certified

Foundation™ fieldbus H1 instruments. They may be installed in

Zone 1 (gas) or Zone 21 (dust) hazardous areas, with the trunk

wiring implemented using suitably protected cable and increased

safety (Ex e) connection facilities.

Each enclosure system uses duplicated Fieldbus Barrier

modules in a redundant configuration to achieve significantly

higher system availability than equivalent ‘simplex’ units.

MECHANICAL

Enclosures

An enclosure is required to house and protect the Megablock device coupler and the

F30 Ex ic adaptor for field operation. The type of enclosure must be chosen to suit

both the hazardous atmosphere likely to be encountered and the general conditions

appropriate to its environmental exposure. For installation in hazardous areas, the

enclosure must meet the requirements of a recognised method of protection

according to IEC 60079-0. clause 1.  In addition, the following conditions should

always be considered to ensure safe and reliable operation.

a) Prevent any form of pollution that could compromise the operation.

b) Provide an adequate level of mechanical protection. This can be achieved

by selecting a protected location, a suitable enclosure, or a combination of

both.

c) Ensure that all cable entries and connections are secure by making

provision for the careful routing and securing of all cables.

d)Provide adequate security against unauthorized interference.

e) Conform to the permitted ambient operating temperature range of  –40°C to +70°C.

The F30 adaptor

The F30 adaptor is connected in series with the trunk wiring to the Megablock (see

Figure 2.1) and limits the voltage to ensure that the ‘Uo’ at the Megablock spurs is

less than the 17.5V value required for compatibility with FISCO-certified instruments.

Where the voltage arriving at the F30 is higher than this (for example, if the trunk

cable is only short in length resulting in only a small voltage drop in the cable), the

F30 regulates the voltage to less than 17.5V.  Final current limiting for each spur is

provided by the short-circuit limiting circuits built in to the F300 Megablock, for which

Ex ic approval already exists. As a result, the combination of F30 and F300 meets the

requirements for Ex ic voltage and current limitation.

The F30 is designed for use only with MTL F304. F308 and F312 Megablock types,

typically providing up to twelve Ex ic spurs per fieldbus segment.  These spurs

may be all from one F312 Megablock in one enclosure, or distributed between two

separate enclosures – see Section 4.7.

The spurs are compatible with FISCO and Entity certified fieldbus instruments, and

where FISCO instruments are selected, cable parameter calculations are not required.

Power supplies

For Ex ic spur applications, the F30 and associated Megablock must be supplied by

9192-FP power supply modules in simplex or redundant configuration. The 9192

FP module has the necessary voltage limiting and is designed to fit on one of the

backplanes from the 918x-x2 range of fieldbus power supply systems, all of which

are capable of providing n+1 redundancy for maximum availability.

The 918x family of redundant power supplies contains a range of solutions to suit

different host interfaces, consult Eaton for the model appropriate to the host and

install the chosen model in accordance with the instructions provided with it.

DESCRIPTION

The Ex ic concept

In May 2013 the Ex nL certification method was removed from the IEC60079-15

standard, and replaced by intrinsic safety method Ex ic in IEC60079-11.  Although Ex

ic and Ex nL are broadly similar, Ex ic brings with it additional requirements that are

associated with the wider intrinsic safety approach.

Ex ic is a new level of protection under the intrinsic safety protection method,

suitable for use in Zone 2 only, where Ex ic circuits may be ‘live-worked’ in the

presence of a flammable atmosphere.  It follows the same energy-limitation principles

as all intrinsically safe circuits, but safety is maintained only in ‘normal operation’.

Host H1 control system

In a typical network installation using the F30 Ex ic Adaptor, F300 Megablock and

9192-FP power supply module, the H1 interface of the host control system is

electrically connected in parallel with the fieldbus trunk circuit. The H1 interface

and host control system are not required to carry hazardous area certification in

this application, but they must comply with electrical safety standards IEC61010 or

IEC60950.  Apparatus carrying a CE mark will comply with this requirement. This

requirement also applies to any other apparatus that is connected electrically in

parallel with the fieldbus trunk circuit.