YOKOGAWA RAKD series, User Manual, Page: 65 / 72

<A1. SAFETY INSTRUMENTED SYSTEMS INSTALLATION>
A1-3
IM 01R01B30-00E-E 6th edition October 01, 2014 -00
All Rights Reserved. Copyright © 2003, Rota Yokogawa
A1.2.6 Startup Time
The flow meter will generate a valid signal within 0.5 seconds of power-on startup.
A1.2.7 Reliability data
A detailed Failure Mode, Effects, and Diagnostics Analysis (FMEDA) report is available from Rota Yokogawa
with all failure rates and failure modes. Rota Yokogawa RAKD variable area flow meter is intended for use
in a Low Demand Mode. Low Demand Mode means the average interval between dangerous conditions
occurs infrequently.
The Rota Yokogawa RAKD variable area flow meter is certified up to SIL2 for use in a simplex (1oo1)
configuration, depending on the PFD
AVG
calculation of the entire Safety Instrumented Function.
A1.2.8 Lifetime limits
The expected lifetime of the Yokogawa Rota Yokogawa RAKD variable area flow meter is 10 years. The
reliability data listed in 2.7 is only valid for this period. The failure rates of the Rota Yokogawa RAKD variable
area flow meter may increase sometime after this period. Reliability calculations based on the data listed in
A1.2.7 for Rota Yokogawa RAKD variable area flow meter lifetimes beyond 10 years may yield results that
are too optimistic, i.e. the calculated Safety Integrity Level will not be achieved.
A1.2.9 Environmental limits
The environmental limits of Rota Yokogawa RAKD variable area flow meter are specified in the User’s
Manual, Model RAKD Small Metal ROTAMETER, IM 01R01B30-00E-E.
A1.2.10 Application limits
The application limits of the Rota Yokogawa RAKD variable area flow meter are specified in the User’s
Manual, Model RAKD Small Metal ROTAMETER, IM 01R01B30-00E-E. If the flow meter is used outside of
the application limits the reliability data listed in A1.2.7 becomes invalid.