Emerson IFT9701 instruction manual Diagnosing zeroing failure, 6.3.2Flow calibration procedure

Models: IFT9701

1 90
Download 90 pages 24.24 Kb
Page 50
Image 50

Configuration with a HART Communicator continued

d.When the display reads “WARN Loop should be removed from automatic control”, isolate the flowmeter from devices that use flowmeter outputs to control the process, then choose F4 (OK).

e.When the display reads “Flow must be zero, perform calibration?”, make sure flow through the sensor is completely stopped, then press F4 (OK).

-The HART Communicator display reads “Calibration in progress” to indicate flowmeter zeroing in progress.

-The meter’s diagnostic LED remains ON and the meter’s optional display reads “ZERO0” for up to one minute during zeroing.

-To end the zero operation before its completion, press F3 (abort).

f.When flowmeter zeroing is completed, the LED blinks ON once per second to indicate normal operation, the optional display indicates the flow rate, and the HART Communicator display reads “Auto zero complete”. Press F4 (OK).

Diagnosing zeroing failure

If zeroing fails:

The HART Communicator display reads “Auto zero failure”.

The meter’s diagnostic LED blinks ON four times per second.

The flowmeter produces fault outputs.

The blinking message “ELEC0” appears in the meter’s optional display. To abort the zeroing procedure, press F3 (abort).

To re-zero, make sure flow is completely shut off and flowmeter tubes are completely filled with fluid, then press F4 (OK).

The most common sources of zeroing failure are:

Flow of fluid through meter during zeroing

Partially empty flow tubes

An improperly mounted meter

Re-zero the flowmeter after correcting the problem, or cycle power to the meter to abort the entire zeroing procedure and return to the previously established zero.

6.3.2Flow calibration procedure

Flow calibration involves adjusting the flow calibration factor so it accurately represents the sensitivity of the flowmeter to mass flow. Performing the flow calibration procedure in the field is optional.

Flow calibration is performed by running a batch of fluid through the meter, weighing the fluid, then using the HART Communicator to compare the weighed amount with the amount of fluid indicated by the flowmeter's mass totalizer. The accuracy of the scale used for weighing the fluid will determine the accuracy of the flow calibration. Use a scale that is highly accurate.

Use a mass flow unit during the calibration procedure. If the application requires volume flow measurement, choose a mass flow unit for the flow calibration, then choose a volume flow unit for the application.

42

Model IFT9701 Transmitter Instruction Manual

Page 50
Image 50
Emerson IFT9701 instruction manual Diagnosing zeroing failure, 6.3.2Flow calibration procedure