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).