B-4Series 90-30/20/Micro Programmable Controllers Reference Manual – September 1998 GFK-0467K
B
PLC Fault Group Fault group is the highest classification of a fault. It identifies the general category of the fault.
Table B-1 lists the possible fault groups in the PLC fault table.
The last non-maskable fault group, Additional PLC Fault Codes, is declared for the handling of
new fault conditions in the system without the PLC having to specifically know the alarm codes.
All unrecognized PLC-type alarm codes belong to this group.
Table B-1. PLC Fault Groups
Group Number
Decimal Hexadecimal Group Name Fault Action
1 1 Loss of, or missing, rack. Fatal
4 4 Loss of, or missing, option module. Diagnostic
5 5 Addition of, or extra, rack. Diagnostic
8 8 Addition of, or extra, option module. Diagnostic
11 B System configuration mismatch. Fatal
12 C System bus error. Diagnostic
13 D PLC CPU hardware failure. Fatal
14 E Non-fatal module hardware failure. Diagnostic
16 10 Option module software failure. Diagnostic
17 11 Program block checksum failure. Fatal
18 12 Low battery signal. Diagnostic
19 13 Constant sweep time exceeded. Diagnostic
20 14 PLC system fault table full. Diagnostic
21 15 I/O fault table full. Diagnostic
22 16 User Application fault. Diagnostic
– – Additional PLC fault codes. As specified
128 80 System bus failure. Fatal
129 81 No user’s program on power-up. Informational
130 82 Corrupted user RAM detected. Fatal
132 84 Password access failure. Informational
135 87 PLC CPU software failure. Fatal
137 89 PLC sequence-store failure. Fatal