ABB Ability 800xA Series, Operation

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Section 6 Status Displays Turbo/Console Node Subsystem Status Display
3BUR002418-600 A 137
With the exception of diagnostic detection of an output channel failure, all of
the above failures to a Control Module automatically initiate the fail over
process. A failed output channel is configured to perform one of the following
four actions based upon a detected diagnostic failure:
– Continue processing the loop as configured.
– Turn the Output FCM off.
– Fail over.
– Turn the loop off.
If, after a fatal diagnostic error, fail over is unsuccessful, either because
redundancy is not available or the switch to back-up did not occur, power to the
outputs of the failed Control Module is turned off. This is accomplished by a
hardware timer that resets the outputs approximately 200 milliseconds after the
card available signal is turned off. If in the HOLD position, the last outputs are
maintained. Otherwise the output values go to zero. If a failure is the result of a
shorted transistor on the digital output, transfer to the Backup Control Module,
whose I/O is paralleled with the Primary, results in the Backup failing also.
This causes the Backup to reset and output power is turned off.
Diagnostics detect if a relay in the analog signal path fails, but is unable to
detect the failure of a relay in the digital signal path.
Turbo/Console Node Subsystem Status Display
The Turbo/Console Node Subsystem Status Display, Figure 61 , provides
information on the specified node’s general condition. The first line of the display
below the Subsystem Status title provides the device number, type and current state
of the Multibus Subsystem. The other areas and activities are described below.