Emerson Network Router Network Router User Manual


 
Installation and Use Manual 71
Meter Verification
Meter Verification Transmitter TerminalsData LoggerTransmitter Configuration
Sensor Operating Conditions
Meter verification is not affected by current process values. However, during the test, process
conditions must be stable. To maximize stability:
Maintain a constant temperature and pressure.
Avoid changes to fluid composition (e.g., two-phase flow, settling, etc.).
Maintain a constant flow. For higher test certainty, reduce or stop flow.
If stability varies outside test limits, the meter verification procedure will be aborted. If this happens,
verify the stability of the process and retry the test.
Notes: If you want the external pressure value displayed in this panel to reflect actual line pressure,
you will need to set up polling of an external pressure measurement device for updated pressure
values. To set up pressure polling, see Section 5.8. Note that if a static pressure value is specified in
the Pressure panel of the Configuration window, it will be displayed here.
Once the test is started, the mass flow, volume flow and density values displayed on this panel will be
fixed and will not be updated for the duration of the test. The temperature and external pressure
values will continue to be updated throughout the test.
Configuration Details
The result of the Structural Integrity meter verification method is not directly affected by changes in
meter configuration or zero value. However, meter accuracy can be affected by changes of certain
configuration parameters or a by a change of the zero value. These indicators show whether the
transmitter's configuration and zero have changed since the last meter verification test. They are green
if configuration and zero are unchanged, and red otherwise. If an indicator is red, you can find out
more information about the changes by clicking the
Details... button next to the indicator. This
information can be useful when reviewing meter verification test results to decide if the meter’s
accuracy meets factory specifications.
Note: The status of these two indicators has no impact on the meter verification procedure. You will
be able to run the test even if these indicators are red.
Meter Verification
When you are ready to start the test, click
Start Meter Verification. ProLink II displays the following
dialog box, which asks you to fix the outputs at either the configured fault levels or the last measured
value. Output levels, as well as mass flow, volume flow and density values reported via digital
communication, will remain fixed for the duration of the test.
To start meter verification:
with outputs fixed at their configured fault levels, click
Fault Configuration.
with outputs fixed at the last measured value, click
Hold Last Value.
A dialog box will appear to warn you that process measurement will be interrupted for the duration of
the test and to ask you if you wish to continue. Ensure that the process will be able to handle the
measurement interruption, then click
OK to start the test.