CPU 03 6 Maintenance
HI 800 479 E Rev. 1.00 Page 29 of 38
6 Maintenance
No maintenance measures are required during normal operation.
If a device or module fails, it must be replaced with a faultless device or module of the
same type or with an approved replacement model.
Only the manufacturer is authorized to repair the device/module.
6.1 Faults
If the test harnesses detect faults in the processor system, the device is rebooted. If a
further internal fault occurs within the first minute after start-up, the device enters the
STOP_INVALID state and will remain in this state. This means that the input signals are no
longer processed by the device and the outputs switch to the de-energized, safe state. The
evaluation of diagnostics provides information on the fault cause.
Module's faults are signaled by the ERR LED located on the front plate. Additionally, the
status parameters can be evaluated in the user program.
NOTE
If a failure occurs, the module must be replaced to ensure the plant's safety.
A module may only be replaced while the power is switched off.
i
Modules may not be removed or inserted during operation.
The instructions specified in Chapter
4.1.1 must be observed when replacing an existing
module or installing a new one.