Omron SYSMAC CJ - REFERENCE MANUAL 01-2008 Reference Manual page 1198

Failure Diagnosis Instructions
1,2,3...
Time Monitoring Function
FPD(269) starts timing when it is executed (when execution condition A goes
ON); it will generate a non-fatal error and turn ON the Carry Flag if the diag-
nostic output is not turned ON within the specified monitoring time.
Execution condition
for FPD(269)
Diagnostic output B
Carry Flag
Note The diagnostic output must go ON within the monitoring time. The teaching
function can be used set the monitoring time automatically.
The following processing will be performed when the Carry Flag is turned ON.
(This processing will not be performed if the FAL number is set to 000 in C.)
1. The FAL Error Flag (A40215) will be turned ON. (PLC operation contin-
ues.)
2. The Executed FAL Number Flag for the specified FAL number will be
turned ON. (Flags A36001 to A39115 correspond to FAL numbers 001 to
1FF.)
3. The corresponding error code will be written to A400. Error codes 4101 to
42FF correspond to FAL numbers 001 to 1FF.
(If a more serious error has occurred (one with a higher error code) at the
same time, the error code of the more serious error will be stored in A400.)
4. The error code and the time/date that the error occurred will be written to
the Error Log Area (A100 through A199).
5. The ERR Indicator on the CPU Unit will flash.
6. If the output mode has been set for bit address and message output (left-
most digit of C set to 8), the ASCII message stored in R+2 through R+10
will be displayed as a non-fatal error message.
Logic Diagnosis Function
Every cycle that the execution condition for FPD(269) is ON, FPD(269) deter-
mines which input bit is causing the diagnostic output to be OFF and writes
the bit's address to the register area beginning at R.
If input bits CIO 000000 through CIO 000003 are all ON in the following exam-
ple, FPD(269) would determine that the normally closed CIO 000002 condi-
tion is causing output CIO 000100 to remain OFF. FPD(269) would turn ON
the Bit Address Found Flag (bit 15 of R) and write the bit address to register
words R+2 to R+4.
Monitoring
time (T)
Non-fatal error generated.
Logic diagnosis block
Logic diagnosis
execution condition
Section 3-30
1159