S-DIAS SAFETY CPU-MODULE
SCP 111-2
08.09.2022
Page 29
During restart, the Safety CPU first runs the
POST
(Power On Self Test). In the POST,
whether the Safety CPU is configured or not is determined. If the Flash memory in the
Safety CPU is empty, it changes to the service mode and switches the status LED (ST)
to continuously on.
a) If the Flash memory of the Safety CPU contains a configuration, it goes into the
idle
/ Check Configuration Mode
. Thereby, an attempt is made to distribute the
configuration; the ST-LED blinks during this process.
b) If the configuration is successfully distributed, the Safety CPU either goes into the
Operational mode
or the
Temporary Operational mode
depending on whether or
not the configuration has already been validated. If the System was already
validated, the ST-LED turns off and the RN-LED lights. If the system has not been
validated, both LEDs light simultaneously.
c) If for whatever reason the distribution of the configuration is still unsuccessful, the
Safety CPU switches to the
Error mode
and the E-LED lights
d) When the Safety output remains in the
idle / Check Configuration Mode
for a long
period of time (ST-LED blinking) without switching to the
Error mode
, it is an
indication of a malfunction in the bus communication. In this case, the PLC will
remain in the error status and must be restarted.
e) A change to the error status can also occur from the POST and (Temp.) OP mode
if other (internal) errors are detected or errors in remote modules occur. The analysis
of these errors, however, requires the use of the Safety Designer.
7.2
Configuration Distribution Error
If the Safety CPU fails to distribute the configuration, the cause can be traced to one or
more of the following errors.
•
The configuration and the physical topology do not match
•
One or more modules are missing
•
More than one module was exchanged
•
Communication error with a remote module
•
The module to be configured is in error status
