Emerson Rosemount 8732 manual 8714I Meter Verification, Initiating 8714i Meter Verification, All

Rosemount 8732

Reference Manual

00809-0100-4665, Rev AA August 2010

8714I METER VERIFICATION

Sensor Signature

Parameters

8714i Meter Verification Test Scope

The 8714i Meter Verification diagnostic provides a means of verifying the flowmeter is within calibration without removing the sensor from the process. This is a manually initiated diagnostic test that provides a review of the transmitter and sensors critical parameters as a means to document verification of calibration. The results of running this diagnostic provide the deviation amount from expected values and a pass/fail summary against user-defined criteria for the application and conditions.

Initiating 8714i Meter Verification

The 8714i Meter Verification diagnostic can be initiated as required by the application. If the advanced diagnostic suite (D02) was ordered, then the 8714i Meter Verification diagnostic will be available. If D02 was not ordered or licensed, this diagnostic will not be available.

The sensor signature describes the magnetic behavior of the sensor. Based on Faraday’s law, the induced voltage measured on the electrodes is proportional to the magnetic field strength. Thus, any changes in the magnetic field will result in a calibration shift of the sensor.

Establishing the baseline sensor signature

The first step in running the 8714i Meter Verification test is establishing the reference signature that the test will use as the baseline for comparison. This is accomplished by having the transmitter take a signature of the sensor.

Having the transmitter take an initial sensor signature when first installed will provide the baseline for the verification tests that are done in the future. The sensor signature should be taken during the start-up process when the transmitter is first connected to the sensor, with a full line, and ideally with no flow in the line. Running the sensor signature procedure when there is flow in the line is permissible, but this may introduce some noise into the signature measurements. If an empty pipe condition exists, then the sensor signature should only be run for the coils.

Once the sensor signature process is complete, the measurements taken during this procedure are stored in non-volatile memory to prevent loss in the event of a power interruption to the meter.

The 8714i Meter Verification can be used to verify the entire flowmeter installation, or individual parts such as the transmitter or sensor. This parameter is set at the time that the 8714i Meter Verification test is initiated.

All

Run the 8714i Meter Verification test and verify the entire flowmeter installation. This parameter results in the verification test performing the transmitter calibration verification, sensor calibration verification, coil health check, and electrode health check. Transmitter calibration and sensor calibration are verified to the percentage associated with the test condition selected when the test was initiated.

Flowtube Sensor

Run the 8714i Meter Verification test on the sensor only. This results in the verification test checking the sensor calibration to the limits of the test criteria selected when the 8714i Meter Verification test was initiated, verifying the coil circuit health, and the electrode circuit health.

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