Automatic Diagnostic Action; Without Time Constraint Configuration; With Time Constraint Configuration; Long Process Time Constraint System - ABB Triguard SC300E Safety Manual

1 Logic Supply B power fail fault
2 Logic Supply C power fail fault
3 Reserved
4 Reserved
5 Reserved
6 Field power fail fault
7 Output discrepancy error
8 Reserved
9 Reserved
10 Reserved
11 Reserved
12 Reserved
13 Reserved
14 Reserved
15 Reserved
The following alarm contacts are available and can be wired into the system for use by the
application logic.
Power supply fault
System cabinet over-temperature
Fuse failure
Watchdog monitoring alarms
3.5.9

Automatic Diagnostic Action

Certain actions, dependent on configuration, must be taken by the application logic on the result
of certain error flags and combination of error flags.

3.5.10 Without Time Constraint Configuration

If a system is configured without time constraint (eg each critical process parameter is controlled
by at least two separate digital output modules), then only annunciation of diagnostics is
required.

3.5.11 With Time Constraint Configuration

If a system is configured with time constraint (eg any critical process parameter is controlled by
a single TMR digital output module) then Global Output bit is used to start a timer equal to the
time constraint of the Output Module and when this timer has elapsed an ESD command should
be instigated. Example shown in Appendix 1

3.5.12 Long Process Time Constraint System

For systems controlling a process that has single inputs configured using the single slot hot
repair facility then the "Single Slot Off-Line" error flag must be used to start a timer equal to the
process time constraint. When this timer is elapsed an ESD command should be instigated.

3.5.13 Initialisation Flags

This flag indicates a wrong configuration of I/O modules or an I/O module or modules missing.
Although these errors are inherently fail safe (eg when an on-line output module is removed its
outputs automatically fail-safe).
Issue 5 - September 2006

Table 4 Piano and Analogue Fault Flags

2 off, any system or field power supply
Cabinet high temperature \ ventilation
alarm, if fitted.
Any fuse failure, grouping being application
dependent.
3 off inputs monitoring the external
triplicated watchdog.

Table 5 System Alarms

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