Emerson 9739 Manuel D’Utilisation

Zero Time

 controls the amount of time the transmitter takes to determine its zero-

flow reference point. The default Zero Time is 20 seconds. For most applications, the
default Zero Time is appropriate.

5.

Click Perform Auto Zero.

The Calibration in Progress light will turn red during the zero procedure. At the end of
the procedure:

•

If the zero procedure was successful, the Calibration in Progress light returns to
green and a new zero value is displayed.

•

If the zero procedure failed, the Calibration Failure light turns red.

Restore normal flow through the sensor by opening the valves.

  

If the zero fails:

•

Ensure that there is no flow through the sensor, then retry.

•

Remove or reduce sources of electromechanical noise, then retry.

•

Set Zero Time to a lower value, then retry.

•

If the zero continues to fail, contact Micro Motion.

•

If you want to return the flowmeter to operation using a previous zero value:

-

To restore the zero value set at the factory: ProLink > Zero Verification and Calibration > Calibrate
Zero

 > Restore Factory Zero .

-

To restore the most recent valid value from transmitter memory: ProLink > Zero Verification
and Calibration

 > Calibrate Zero > Restore Prior Zero . Restore Prior Zero is available only while the

Flow Calibration window is open. If you close the Flow Calibration window, you will no
longer be able to restore the prior zero.

Restore the factory zero only if your flowmeter was purchased as a unit, it was zeroed at the factory,
and you are using the original components.

9.2.3

Zero the flowmeter using the Field Communicator

Zeroing the flowmeter establishes a baseline for process measurement by analyzing the
sensor's output when there is no flow through the sensor tubes.
1.

Prepare the flowmeter:

a. Allow the flowmeter to warm up for at least 20 minutes after applying power.
b. Run the process fluid through the sensor until the sensor temperature reaches

the normal process operating temperature.

c. Stop flow through the sensor by shutting the downstream valve, and then the

upstream valve if available.

d. Verify that the sensor is blocked in, that flow has stopped, and that the sensor is

completely full of process fluid.

Measurement support

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