Eaton MTL F880 8 Segment Redundant Fieldbus Power Supply

OVERVIEW

The F880 redundant fieldbus power supply is designed to provide redundant power

for eight (8) Foundation fieldbusTM H1 segments. Connections are provided on the

F880-Cx Carrier for two redundant pairs of Yokogawa ALF111 fieldbus cards using

Yokogawa AKB336 cables. Power for the eight fieldbus segments is provided by two

F801 or F802 Power Modules mounted to the carrier and operating in a redundant

configuration. Failure alarms, galvanic isolation, power conditioning and segment

termination are incorporated into each Power Module. A single Power Module may

be used where redundancy is not required.

DESCRIPTION

For maximum reliability, the module carrier contains no components and only provides

interconnections between the power modules and the external connections. The

carrier circuit board is supported in a rigid metal frame that protects it from mechanical

damage. Secure DIN-rail mounting is provided by integrated fixings. The F801 or

F802 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

FoundationTM FF-831 validation test for fieldbus power supplies. There is also galvanic

isolation between the fieldbus segments, thereby preventing cross-talk between

segments in the event of ground faults in the field wiring. Each segment has its own

current limitation and passive fieldbus power conditioner. Termination of the fieldbus

segment is automatically maintained when single or redundant F801 or F802 modules

are fitted. The F880-Cx carrier is equipped with connectors that will accept an F809F

diagnostic module. The module continuously monitors the performance of each of the

eight fieldbus segments, providing information on the network health.

Each Power Module has indicator LEDs to show both its status and that of the eight

segments under power. In normal operation, each green ‘Segment’ LED is lit, showing

that the segment is powered. If a segment is shorted, or its voltage is below the rated

output, its LED is extinguished, and the red ‘Alarm’ LED is lit. Redundant 24V DC (nom.)

input power is connected to the F880-Cx carrier using two-part pluggable connectors.

Field wiring connections are available with either pluggable screw terminals (F880-*S)

or pluggable spring clamp terminals (F880-*C).

Three variants of carriers are available in the F880 family to be used in two different

types of installations. For large installations where multiple F880 systems will be

installed in a cabinet, there are Left (F880-CL) and Right hand (F880-CR) versions

that make cabinet wiring symmetrical – see Figure 2b. In smaller installations where

carriers are not installed side-by-side, the F880-CA carrier provides terminal numbering

and consistent connector polarity.