Evaluation Of The Sf Led (Software Error) - Siemens SIMATIC S7-300 Hardware And Installation Manual

Table 10-3
Possible Errors
TOD interrupt is enabled and
triggered. However, a
matching block is not
loaded.(Software/
configuration error)
Start time of the enabled
TOD interrupt was jumped,
e.g. by advancing the
internal clock.
Delay interrupt triggered by
SFC 32. However, a
matching block is not
loaded. (Software/
configuration error)
Process interrupt is enabled
and triggered. However, a
matching block is not
loaded. (Software/
configuration error)
Attempt to access a missing
or faulty module. (Software
or hardware error)
The cycle time was
exceeded. Probably too
many interrupt OBs called
simultaneously.
Programming error
•
Block not loaded
•
Wrong block number
•
Wrong timer/counter
number
•
Read/write access to
wrong area
•
etc.
I/O access error
An error has occurred when
module data was accessed
Global data communication
error, e.g. insufficient length
of the DB for global data
communication.
S7-300 Programmable Controller Hardware and Installation
A5E00105492-01
Testing functions, Diagnostics and Fault Elimination

Evaluation of the SF LED (Software error)

Reaction of the CPU
OB 85 call. CPU goes
into STOP if OB 85 is
not loaded.86
OB 80 call. CPU goes
into STOP if OB 80 is
not loaded.
OB 85 call. CPU goes
into STOP if OB 85 is
not loaded.
OB 85 call. CPU goes
into STOP if OB 85 is
not loaded.
OB 85 call. CPU goes
into STOP if OB85 is
not loaded or, with
loaded OB 80, if the
cycle time is
exceeded a second
time without having
been retriggered.
OB 80 call. CPU goes
into STOP when
OB 80 is not loaded or
called twice.
OB 121 call. CPU
goes into STOP if OB
121 is not loaded.
OB 122 call. CPU
goes into STOP if OB
122 is not loaded.
OB 87 call. CPU goes
into STOP if OB 87 is
not loaded.
Remedies
Loading OB 10 or 11 (CPU 318-2
only) (OB number can be viewed in
the diagnostic buffer).
Disable the TOD interrupt before
you set the time-of-day with
SFC29.
Loading OB 20 or 21 (CPU 318-2
only) (the OB number can be
viewed in the diagnostic buffer).
Loading OB 40 or 41 (CPU 318-2
only) (the OB number can be
viewed in the diagnostic buffer).
Generate OB 85, the start
information of the OB contains the
address of the respective module.
Replace the respective module or
eliminate the program error.
Extension of the cycle time
(STEP 7 – Hardware
configuration), changing the
program structure. Remedy: if
required, retrigger cycle time
monitoring via SFC 43
Eliminate the programming error.
The STEP 7 testing function helps
you to localize the error.
Check module addressing in HW
Config or whether a module/DP
slave has failed.
Check global data communication
in STEP 7. If required, correct the
DB size.
10-9