Affordable pluviometer part 2 – strain gauge measurements

Affordable precision pluviometer PART 1 (introduction and construction) is here.

Here are first analog measurements of the affordable precision pluviometer:

mL uV uV/mL
0 550
10 568
30 606 1.87
50 643 1.86
100 736 1.86
200 924 1.87
300 1109 1.86
400 1296 1.87
500 1483 1.87
600 1672 1.87
650 1762 1.86
700 1853 1.86
750 1949 1.87

The measurement setup was: measuring graduated cylinder (4) strain gauge sensor (3) from kitchen scale, power suuply (2) and digital multimeter (1):

meas1

The measured output voltage vs. volume (water mass) was:

output

and the sensitivity was pretty consistent:

sens

Next step: add some ADC with PGA for digital measurements. I will try to measure the sensitivity vs. temperature, but from my experience I am not expecting very high error due to temperature changes.

Another important information is the maximum volume before automatic drain: 785mL.

Some additional photos of today experiment:

meas2 meas3

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