MSP430FR6047: Issue with Calibration kit MSP430FR6047 and Audiowell pipe

Dear friends in TI forum:

Good day, hoping that all of you are ok, please your support with the next:

In order to take practice with calibration using the ultrasonic kit MSP430FR6047 we are trying to calibrate an AudioWell tube size DN15 for water meter, we are proposing 3 ranges with the next calibration points:

To start the calibration, we begin with the range#1 with 2 calibration points: 60 LPH and 150 LPH, we reach these flows in our test bench,

Following the steps of Run-Time Calibration:

Calibration — Ultrasonic Sensing Design Center User Guide 02.20.00.15 documentation

In the next video we show the steps we follow to calibrate it in these 2 points:

As a comment we are leting pass the necessary times for the readings.

Question#1:

If we are running a test and the flow that is selected in our test bench is 60 LPH: we must put 60 in the box "Expect Volume Flow Rate (VFR)?

At the end of the calibration in the box "Enter the current Averaged Volume Flow Rate" also we must put 60 ? 

We ask this because we consider that the flow is kept constant in our test bench.

Question#2:

We want to know what we are missing or what we are doing badly because after following the steps of the calibration guide we cannot obtain the expected flows, at 60 LPH we get 35.5 LPH and at 150 LPH we get 85.5 LPH.

Please could you kindly check and give us your comments, if you have some question please let us know, thank you very much

Best Regards

Jose