Chapter 4 Operating Constraints; Reverse Flow; Reliability Data - Emerson Rosemount 8800D Series Safety Manual

4 Operating Constraints
Topics covered in this chapter:
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4.1

Reverse flow

Use appropriate means to ensure only zero or forward flow through the meter, as
indicated by the arrow on the meter body. Reverse flow operation may result in erroneous
non-zero flow indication.
4.2

Reliability data

The Rosemount 8800D Series SIL 2/3 Capable Vortex Flowmeter:
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FMEDA report
The Failure Mode, Effects, and Diagnostics Analysis (FMEDA) report is used to calculate the
failure rate. A FMEDA report for a Vortex Flow Meter with a Rosemount 8800D transmitter
contains:
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Obtain a FMEDA report at www.emerson.com/vortex.
Environmental and application limits
See the product data sheet for environmental and application limits.
Using the flowmeter or transmitter outside environmental or application limits invalidates
the reliability data in the FMEDA report.
Safety Manual
Reverse flow
Reliability data
Report failures
Has a specified safety deviation of 2%. Internal component failures are listed in the
device failure rate if they will cause an on-scale error of 2% or greater.
Reports an internal failure within 30 minutes of fault occurrence – worst case
scenario.
Generates a valid signal within 6 seconds plus configured damping response of a
power-on startup.
All failure rates and failure modes
Common cause factors for applications with redundant devices that should be
included in reliability calculations
The expected lifetime of your flowmeter and transmitter, as the reliability
calculations are valid only for the lifetime of the equipment
Operating Constraints
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