I have a reservoir with diameter 50mm and height 400mm. Using an AQ mps pressure delta 40 with setting as level sensor delta 500. The top of the mps is a couple of millimeters lower than the bottom of the reservoir.

The procedure I've seen is to fill the tank up to 50%, enter the max level in mm and the current level in mm and click calibrate.

This seems to be working only for a small range around 50%, so I tried different levels above 50% and found the range it measure correctly to be smaller and smaller. So, I started a manual calibration that gave me some strange data.

It seems to be a quadratic curve that is so steep after 60% that it's close to useless. So, either my mps is too small or you just can't get a level above 60% with a good certainty.

Here is my data:

10% = 566
20% = 639
30% = 717
40% = 795
50% = 876
60% = 954
70% = 966
80% = 966

The fill level percentage at every point isn't absolutely exact, but it's close. Up to 60% the formula I've used is y=78x+483, but the steep climb after 60% means that it isn't a linear, but a quadratic curve. I have changed the curve to the following, basing it on the linear formula up to 60%:

0% = 483
10% = 561
20% = 639
30% = 717
40% = 795
50% = 873
60% = 951
67% = 959
75% = 963
81% = 965
90% = 966 (what I have on the tank now)
100% = 967

Has anyone else been looking into this problem?

Zitat von »Shoggy«

Zitat von »SverreMunthe«

I have a reservoir with diameter 50mm and height 400mm. Using an AQ mps pressure delta 40 with setting as level sensor delta 500.

This is the wrong setting. Must be 40 too.

Thanks. Will it be good enough fir a 400mm tank?

Zitat von »Shoggy«

Yes, the delta value can be converted 1:1 to the height in centimeter that the sensor can measure.

Just sent you this e-mail

Tried again, with level 40, but it didn't work. Here's a short description.

This is looking kind of messy in the preview, not sure how I should format it.

X Y diff Y2
0 318 36 318
5 0 0 356
10 390 36 394
15 0 0 432
20 463 39 470
25 502 44 508
30 546 31 546
35 577 48 584
40 625 37 622
45 662 36 660
50 698 44 698
55 742 37 736
60 779 24 774
65 803 0 812
70 0 0 850
75 0 0 888
80 0 0 926
85 0 0 964
90 0 0 1002
95 0 0 1040
100 0 0 1078

Average difference 37,5
Smoothed difference 38,0
Y = Measured value
Y2 = Y from assumed formula
Assumed formula: Y=7,6X+318 (7,6 = smoothed difference per percent; 318 is the starting point)
Curve stops at Y=803 which gives X=63,81

Can I assume that this means that the mps pressure delta 40 that I have isn't capable of measuring a column of water higher than 400*0,6381=255mm?
In the manual it says 400mm, which is the height of my tank. Hoping I'm screwing up again.