I did the first round of the re-calibration tonight on the rain sensor. Based on 314ml of water through the gauge representing 10ml of rain fall, and given a 200mm diameter collector, I set the correction factor in the TX sketch back to 0.200.
The first test I did was to manually perform 50 tips (by hand - no water), and I now get exactly 10ml of rainfall on the WD RX Display.
Next a quick bit of math. I divided down the test water amount and get ml / tip - 314 (ml) / 50 (tips) = 6.28ml (per tip). This is what I'm looking for in each bucket tip.
I set the gauge level, using the built-in (bullseye) spirit level. Then I adjusted the see-saw left/right, until I had it balancing deed in the middle. Next I used an eye dropper and set each bucket tip, as best I could, to 6.28ml per tip. Each time I would adjust the tipper mechanism with the set screw, and repeat. Eventually I got each bucket tip (side) set and was equal, and tipping 6.28ml per tip on each side.
I then measured out 314ml of water and ran it through the rain gauge as slow as I could. You need to get it down to "dripping" into the bucket, as the waistage if it is running though can be as much as 6 or 8 buckets (short / in error). You need the bucket to tip between drips. It really does make that much difference. Dripping it through, best I could, I got 49 tips for 314ml of water, which read 9.80ml rainfall on the WD RX display. So pretty close for a first try.
Next up, I am going to get a (new) hospital drip bag and line, and see if I can use that to do a slower and more accurate test, and repeat it over a few times. As needed, the next adjustment will be the counter weight, which should adjust both tip amounts equally (increase or decreased, as needed) when screwed up or down. Then rinse and repeat, as they say...
So for now, I think I've got it pretty close, and some more testing to come. Will keep you updated.
Cheers for now...
Mark R
The first test I did was to manually perform 50 tips (by hand - no water), and I now get exactly 10ml of rainfall on the WD RX Display.
Next a quick bit of math. I divided down the test water amount and get ml / tip - 314 (ml) / 50 (tips) = 6.28ml (per tip). This is what I'm looking for in each bucket tip.
I set the gauge level, using the built-in (bullseye) spirit level. Then I adjusted the see-saw left/right, until I had it balancing deed in the middle. Next I used an eye dropper and set each bucket tip, as best I could, to 6.28ml per tip. Each time I would adjust the tipper mechanism with the set screw, and repeat. Eventually I got each bucket tip (side) set and was equal, and tipping 6.28ml per tip on each side.
I then measured out 314ml of water and ran it through the rain gauge as slow as I could. You need to get it down to "dripping" into the bucket, as the waistage if it is running though can be as much as 6 or 8 buckets (short / in error). You need the bucket to tip between drips. It really does make that much difference. Dripping it through, best I could, I got 49 tips for 314ml of water, which read 9.80ml rainfall on the WD RX display. So pretty close for a first try.
Next up, I am going to get a (new) hospital drip bag and line, and see if I can use that to do a slower and more accurate test, and repeat it over a few times. As needed, the next adjustment will be the counter weight, which should adjust both tip amounts equally (increase or decreased, as needed) when screwed up or down. Then rinse and repeat, as they say...
So for now, I think I've got it pretty close, and some more testing to come. Will keep you updated.
Cheers for now...
Mark R
