The assembly uses duplicated fieldbus barrier modules in

a redundant configuration to achieve significantly higher system

availability than equivalent ‘simplex’ units. The 9387-FB-R 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 9387-FB-R redundant fieldbus barrier assembly is based on

the 9370-FB range of products, which are supplied as complete,

factory-assembled systems that do not require additional wiring or

complex ancillary components. The electrical and mechanical aspects

of this design have been integrated to provide the industry’s first

complete, ergonomic solution for ‘High Energy Trunk’ applications in

hazardous areas.