SmartPLC SafeLine with PROFIBUS slave interface
22
3.3.2
Operating states of AC412S
42321
AC412S has the following operating states:
INIT
NORMAL OPERATION
SYSTEM STOP
Below the state chart:
INIT
After the start the device automatically goes into the INIT state (
). In the INIT state the device
undergoes the different hardware and integration tests (PBIT = Power-up Built-In Test). If the PBIT
test is successfully passed, the device takes the state NORMAL OPERATION (
). If the PBIT
test is not passed, the device passes into the SYSTEM STOP (
).
NORMAL OPERATION
In NORMAL OPERATION the device of Standard-SPS and the fail-safe PLC provides a working
environment. The states and the operation modes of the PLC applications are valid (see
programming manual). Simultaneously and irrespective of the processing of the PLC applications
the device continuously undergoes different hardware tests (CBIT = continuous built-in test). If this
CBIT test is not passed, the device goes into the SYSTEM STOP state (
).
SYSTEM STOP
In SYSTEM STOP the device is in the safe state. To leave the SYSTEM STOP state the operator
has to carry out a power-on reset. The device changes to the INIT state (
).