Vigilantplant TDLS8000, Руководство пользователя

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<Appendix 7 Safety Instrumented System Installation>
App.7-3
IM 11Y01D01-01EN
The proof test interval is determined by the safety calculation that is performed for each safety
instrumented function, including the TDLS8000. To maintain the safety level of the safety
instrumentation, proof tests must be performed at a frequency determined by the safety
calculation or a higher frequency.
The following tests must be performed in a proof test. The result of proof tests must be
documented, and the documents should be handled as part of the plant’s safety management. If
a fault is detected, please consult with Yokogawa.
The operator that performs proof tests on the TDLS8000 must have a thorough knowledge of
the operation of Safety Instrumented Systems, including the bypass procedure, TDLS8000
maintenance, and change procedures.
Test method Required tools Estimated result
1. Bypass the safety functions, and perform appropriate measures to
prevent malfunction.
HART
Configuration tool
or
YH8000
Proof test
coverage: 92%
2. Use the HART Configuration tool or YH8000 to properly execute all
diagnostics and collect the results.
3. Use the loop function of the HART Configuration tool or YH8000 to
output a burn-up current, and verify that the current is at this level.
4. Use the loop function of the HART Configuration tool or YH8000
to output a burn-down current, and verify that the current is at this
level.
5. Thoroughly check for leakages and visible damages and stains.
6. Perform two-point validation over the entire operating range.
7. Release the bypass, and restore normal operation.
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Repair and replacement
To repair the TDLS8000 while the process is online, bypass the TDLS8000. You must perform
the bypass procedure correctly. If a fault is detected, please consult with Yokogawa. TDLS8000
replacement must be performed by a trained engineer.
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Startup time
The TDLS8000 sends valid signals within 5 minutes after power-on.
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Firmware updating
For firmware updating, please consult with Yokogawa.
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Reliability data
The FMEDA (Failure Mode, Effects and Diagnostic Analysis) report that Yokogawa provides
contains failure rates and failure modes.
When used by itself, the TDLS8000 is certified for compliance with up to Safety Integrity
Level (SIL) 2 based on a PFDavg calculation of the entire safety instrumented function. The
development process of the TDLS8000 is certified for compliance with up to SIL3. When used
in a redundant configuration, it can be used at Safety Integrity Level (SIL) 3 based on a PFDavg
calculation of the entire safety instrumented function.
When used in a redundant configuration, we recommend that the common cause factors
(β-factor) for the PFD calculation of the entire safety instrumented function be set at 5%. If the
plant operator provides “common cause failure” training and a clear, detailed maintenance
procedure for preventing common cause failures, the common cause factors (β-factor) can be
set to 2%.
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Lifetime limitation
The expected lifetime of the TDLS8000 is 10 years. The reliability data in the FMEDA report is
valid to 10 years. It is assumed that the failure rates of the TDLS8000 would increase when it is
used over 10 years. Therefore, the safety integrity level based on the reliability data given in the
FMEDA report may not be attainable.
3rd Edition: Jun. 10, 2016-00