Zero Level Trim
Starting at the Calibration screen, select the Zero Level Trim procedure. This procedure trims the Level digital value measurement at the position that the user desires to be the zero reference position.
If the user selects Zero Level Trim from the Calibration screen, this screen will appear reminding the user that the loop should be removed from automatic control before proceeding. When this has been done, the user must press OK to continue.
This screen warns the user that proceeding will affect the sensor calibration. The user must press OK when ready to proceed
The HART Communicator now requests that the level float be set to the desired zero level trim point. When the float is at this position, the transmitter will always report 0 in the user chosen units. The user must press OK when the float is at that position.
The transmitter will take several seconds to insure that the level signal has stabilized. Once the measurement is stable, the procedure will continue without user intervention. The HART communicator will then send the command to the transmitter to calculate the new Level zero
calibration constant.
When the transmitter has completed its calculation it will reply to the HART Communicator. Then the HART Communicator will inform the user that the zero level point has been trimmed.
The user is then notified that the loop may now be returned to automatic control. After the user presses OK the HART Communicator returns to the Calibration screen.
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The HART Communicator is now at the starting screen for the Zero Level Trim.
Full Level Trim
Starting at the Calibration screen, select the Full Level Trim procedure. This procedure trims the Level digital value measurement at two points. The first point is the position that the user desires to be the zero reference position. The second point is a Level position near the end of the sensor.
If the user selects Full Level Trim from the Calibration screen, this screen will appear reminding the user that the loop should be removed from automatic control before proceeding. When this has been done, the user must press OK to continue.
This screen warns the user that proceeding will affect the sensor calibration. The user must press OK when ready to proceed.
The HART Communicator now requests that the level float be set to the desired zero level trim point. When the float is at this position, the transmitter will always report 0 in the user chosen units. The user must press OK when the float is at that position.
The transmitter will take several seconds to insure that the level signal has stabilized. Once the measurement is stable, the procedure will continue without user intervention. The HART communicator will then send the command to the transmitter to calculate the new Level zero calibration constant.
When the transmitter has completed its calculation it will reply to the HART Communicator. Then the HART Communicator will inform the user that the zero level point has been trimmed.
