2 - Fagor Automation

Functional safety
9.
FUNCTIONAL SAFETY
Maintenance, repair and analyze hazardous events
326
DDS
HARDWARE
Ref.1307
324
9.10 Maintenance, repair and analyze hazardous events
Although it is not required due to its low probability, FAGOR recommends
to demand the STO safety function at least once every 24 hours in order
to detect possible failures in the STO circuit.
The external main contactor - KM1 and Drive Enable have electromechanical
components that wear out in time. Their failures due to deterioration
must be detected by the diagnostics of the safety controller.
The test interval of the Drive Enable is the same as its useful life, i.e. 20
years. After this period, the Drive Enable is no longer reliable.
The useful life (mission) of the STO safety function is 20 years. After that
time, the safety function will no longer be valid. The expiration date must
be calculated by adding 20 years to the date shown on the version label
of the unit. Write down this value in the maintenance plan of the installation.
Do not use the safety function after that date.
If the STO safety function has been implemented according to ISO 13849
PL d (see examples in this chapter), the safety controller will detect an
error at the Drive Enable reading AS1-AS2 or and error at external main
contactor - KM1 with its feedback contact only when carrying out a demand
of the STO.
If the external main contactor - KM1 breaks down, it must be replaced.
Repair
Neither the user nor the OEM is authorized to repair any AXD/SPD
modules, not even to replace boards.
If the Drive Enable circuit breaks down, the AXD/SPD must be replaced
and commissioning test and registering must be done again.