Safety function
The TONiC FS encoder system provides 1 Vpp (nominal) sine and cosine outputs, where the sine
and cosine outputs are 90° phase shifted, in order for the evaluation unit to perform incremental
counting and thereby confirm machine position is within safe limits.
The following restrictions apply to this claim:
•
The system installer must perform a verified commissioning test during installation.
•
The system repairer must perform a verified commissioning test following replacement of a
system part.
•
When installed correctly, the TONiC FS system shall have mechanical safe position not
exceeding ±1 mm
NOTE: Thermal expansion effects of the scale and readhead mounting tolerances are
excluded from the mechanical safe position.
•
The TONiC FS system includes no self-diagnostic function.
NOTE: Faults are detected only by the evaluation unit monitoring. When errors are detected it
is the responsibility of the system manufacturer to place the system into a safe state.
Original instructions
Fault exclusions
The following actions will invalidate the Functional Safety certification of the TONiC FS system:
•
Faults caused by cutting and reconnecting the readhead cable or extending the
readhead cable.
•
Incorrect installation of the readhead.
•
Incorrect installation of the RELM20 or RSLM20 scale.
•
Failure to follow the instructions contained within this installation manual.
•
Dismantling of the TONiC readhead, Ti0000A00A interface or the DOP interface.
•
Operating the system outside of the limits specified within this installation manual.
Failure modes
Failure modes are detected by evaluation unit monitoring. See
declaration'on page
11
for a summary of the FMEDA.
NOTE: For the purposes of the FMEDA calculation the following conditions have been assumed:
Method
Environment
Temperature
'Functional Safety data
SN29500-2005-1
Ground mobile
85 °C
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