Functional Safety Compliance - Prerequisites To; Operate The Device - ABB Endura AZ20 Manual

6 E N D U R A A Z 2 0 & A Z 3 0 | OX YG E N A N A LY Z E R | S I/A Z 2 0/A Z 3 0 - E N R E V. A
...5 Zirconia Probe as part of the
safety function system
...Failure rates
Notes:
1 Auto-diagnosed failures are assumed to be dealt within 48
hours. Undiagnosed failures are assumed to be revealed
subject to a proof-test interval of one year.
2 The equipment is in virtually continuous use such that failure
rates (based on 8760 hours per year) are applicable.
6 Functional safety compliance -
prerequisites to operate the device
• The analog signal of the transmitter can be considered safe
after 2 hours (warm up time), or after the heater output
stabilizes (see signal view).
• A dangerous error is an error during which the output of the
transmitter no longer responds to the input signal or deviates
by more than 2 %.
• The maximum reaction time of the device on error is less than
10 minutes.
• Use of the device in a safety-related system is only permitted
within the first 20 years after production of the device. This is
a basis for the calculated failure rates.
• The ambient temperature for use in a safety-related system
must be above –40 °C. The information according to the
operating instructions applies to the upper limit of the
ambient temperature.
• When using the device for the measurement of corrosive
media, keep in mind the limitations referred to in the
operating instructions or data sheet.
• Selection of the correct version of probe or transmitter is the
operator's responsibility.