Endress+Hauser HART Proline Promass 500, Специальная документация

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Proline Promass 500 Manufacturer's Declaration
Hauser 7
Recommended test interval T
1
4 years 3 years
MTTF
d
8)
71 years 73 years 50 years 49 years
1) FIT = Failure In Time, number of failures per 10 9 h
2) Valid for averaged ambient temperatures up to 40 °C (104 °F) in accordance with general standard for devices
with SIL capability.
3) PTC = Proof Test Coverage (diagnostic coverage achieved by device failure detection during manual proof testing)
4) This value takes into account all failure types of the electronic components as per Siemens SN29500
5) All diagnostic functions are carried out at least once during this time.
6) Maximum time between fault detection and fault response.
7) The process safety time amounts to the diagnostic test interval * 100 (calculation as per IEC 61508).
8) MTTF
d
as per ISO 13849/IEC 62061 also includes soft errors (sporadic bit errors in data memories).
Note
The measuring device has been developed for use in "Low Demand" and "High Demand" mode.
Explanation
Our in-house quality management system saves information on safety-related systematic errors that will become
known in the future.