Technical data

Sampling time errors After the selected sampling time has elapsed, the cyclic program is
stopped at the next
block boundary and the controller processing is
inserted. It is possible that the processing of longer blocks takes too
long and that the controller processing becomes "out of step": this
causes a sampling time error.
You can handle a sampling time error just as the other controller
errors (as described on the previous page)
or you can suppress the
error by means of a mask. In this case, program execution is not
interrupted when a sampling time error occurs.
Refer also to the description "compact closed loop control in the R
processor of the S5 135U" in the R64 Controller Structure.
You can sometimes prevent a sampling time error by changing the
default in DX 0 "processing of controller and process interrupts at
block boundaries" to "processing of controller and process interrupts
at operation boundaries".
5.6.8
ABBR (Abort)
If, during the RUN mode, the stop mode is requested by one of the
following:
•• switching the mode selector on the CPU from RUN to STOP,
•• PG online function, PLC STOP,
•• reset switch on coordinator set to STOP (in multiprocessor
operation),
the system program calls
OB 28, it is loaded. After OB 28 has been
processed, the CPU goes into the STOP mode.
Note
The transition to the stop mode takes place regardless of whether
you program OB 28 or not.
No error identifiers No error identifiers are transferred to ACCU 1 or ACCU 2.
Errors in RUN and in RESTART
CPU 928B Programming Guide
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