GE 90-30/20/Micro Manual De Usuario
GFK-0467K
Chapter 3 Fault Explanation and Correction
3-3
3
Note
For information specific to Micro PLC fault handling, refer to chapter 7 of the
Series 90 Micro PLC User’s Manual (GFK-1065).
Series 90 Micro PLC User’s Manual (GFK-1065).
System Reaction to Faults
Typically, hardware failures require that either the system be shut down or the failure is tolerated.
I/O failures may be tolerated by the PLC system, but they may be intolerable by the application or
the process being controlled. Operational failures are normally tolerated. Series 90-30, 90-20, and
Micro PLC faults have two attributes:
I/O failures may be tolerated by the PLC system, but they may be intolerable by the application or
the process being controlled. Operational failures are normally tolerated. Series 90-30, 90-20, and
Micro PLC faults have two attributes:
Attribute
Description
Fault Table Affected
I/O Fault Table
PLC Fault Table
PLC Fault Table
Fault Action
Fatal
Diagnostic
Informational
Diagnostic
Informational
Fault Tables
Two fault tables are maintained in the PLC for logging faults, the I/O fault table for logging faults
related to the I/O system and the PLC fault table for logging all other faults. The following table
lists the fault groups, their fault actions, the fault tables affected, and the “name” for system discrete
%S points that are affected.
related to the I/O system and the PLC fault table for logging all other faults. The following table
lists the fault groups, their fault actions, the fault tables affected, and the “name” for system discrete
%S points that are affected.
Table 3-1. Fault Summary
Fault Group
Fault Action
Fault
Table
Special Discrete Fault References
Loss of or Missing I/O Module
Diagnostic
I/O
io_flt
any_flt
io_pres
los_iom
Loss of or Missing Option Module
Diagnostic
PLC
sy_flt
any_flt
sy_pres
los_sio
System Configuration Mismatch
Fatal
PLC
sy_flt
any_flt
sy_pres
cfg_mm
PLC CPU Hardware Failure
Fatal
PLC
sy_flt
any_flt
sy_pres
hrd_cpu
Program Checksum Failure
Fatal
PLC
sy_flt
any_flt
sy_pres
pb_sum
Low Battery
Diagnostic
PLC
sy_flt
any_flt
sy_pres
low_bat
PLC Fault Table Full
Diagnostic
—
sy_full
I/O Fault Table Full
Diagnostic
—
io_full
Application Fault
Diagnostic
PLC
sy_flt
any_flt
sy_pres
apl_flt
No User Program
Informational
PLC
sy_flt
any_flt
sy_pres
no_prog
Corrupted User RAM
Fatal
PLC
sy_flt
any_flt
sy_pres
bad_ram
Password Access Failure
Diagnostic
PLC
sy_flt
any_flt
sy_pres
bad_pwd
PLC Software Failure
Fatal
PLC
sy_flt
any_flt
sy_pres
sft_cpu
PLC Store Failure
Fatal
PLC
sy_flt
any_flt
sy_pres
stor_er
Constant Sweep Time Exceeded
Diagnostic
PLC
sy_flt
any_flt
sy_pres
ov_swp
Unknown PLC Fault
Fatal
PLC
sy_flt
any_flt
sy_pres
Unknown I/O Fault
Fatal
I/O
io_flt
any_flt
io_pres