Eaton F890 Redundant fieldbus power supply

• Redundant fieldbus power for Foundation™ fieldbus cards

• 8-segment redundancy

• High-density, compact design

• Fully isolated

• Hot swappable power modules*

• Low power dissipation

• Zero component carrier

• On-line diagnostics option

• Redundant power & conditioning

• Vertical DIN-rail mounting

• F801 output 21.5V, 350mA

• F802 output 28V, 500mA

The F890 fieldbus power system is designed to provide redundant

power for eight Foundation™ fieldbus H1 segments when used with

the Emerson DeltaV or another non-proprietary cabled fieldbus system.

Power for the fieldbus segments is provided by two power modules

- F801s or F802s - operating in redundant configuration (load sharing).

Failure alarms, galvanic isolation, power conditioning and segment

termination are incorporated into each F80x module. In simplex

applications, a single F80x module may be used. Termination of

the fieldbus segments is automatically maintained when single or

redundant F80x modules are fitted.

For extreme reliability, the module carrier has no components

and only provides interconnections between the power modules

and external connections. It is supported in a rigid metal frame that

protects the circuit board from mechanical damage. Secure DIN-rail

mounting is provided by integrated fixings.

Each F80x module monitors the output of the eight fieldbus

segments and indicates an alarm by means of a built-in, normally closed

relay if any of the segments is shorted, or below the minimum output

voltage threshold. Failure of either of the bulk power input supplies

is also annunciated. The alarm contacts are volt-free and galvanically

isolated from other circuitry. Connections to the alarm relays are made

via terminals on the F890-CA carrier. A separate alarm module is not

required for this function. LED indicators also show the status of each

F80x module and the eight individual segments. In normal operation,

each segment LED is lit, showing that the segment is powered. If a

segment is shorted, this LED is extinguished, and the module Alarm

LED is lit.

A separate physical layer diagnostics module may be installed on

the carrier to automatically collect and distribute additional diagnostic

information for each of the eight fieldbus segments. For more

information see the F809F product specification.

The F80x module provides galvanic isolation between the 24V DC

input power and the fieldbus segments, as required by the IEC61158

2 fieldbus standard and the Fieldbus Foundation™ FF-831 validation

test for power supplies. There is also galvanic isolation between the

fieldbus segments, thereby preventing multiple segment failures due

to ground faults on more than one segment. Each segment has its

own fieldbus power conditioner and current limitation.

Redundant 24V DC (nom.) input power is connected to the F890

carrier using two-part pluggable connectors. Field wiring connections

are available with either pluggable screw terminals (F890-PS), or

pluggable spring clamp terminals (F890-PC).