Author Topic: Starting to experiment  (Read 4236 times)

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Offline kmahler

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Starting to experiment
« on: October 27, 2016, 11:17:10 PM »
I received my RG-11 about a week ago. Tonight was our first rain since getting it. I hooked it up in bucket mode and attached it to an Arduino Uno. I used some sample code I found on the web. In attempted to make sure everything was working correctly I tired sprinkling water on the sensor. It never registered as rain. Then it started raining, that registered. Has anyone figured out a way to test the device with fake rain? I am impressed it knew the water I sprinkled on it wasn't rain. But, I'd like to find a way to test it instead of waiting for actual rain.

Kevin Mahler
Skywarn Storm Spotter, AKQ3785
CWOP AV286
73 de KO4JY


Offline SLOweather

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Re: Starting to experiment
« Reply #1 on: October 28, 2016, 12:46:47 AM »
What mode is your RG11 in? 0.01" tipping bucket emulator?

Coincidentally, I have been running a little test this evening in our welcome and long needed rain here. I have 2 RG11s going, one in drop counter mode, one in 0.0001" tipping bucket mode, both logged to an industrial controller. More on that in a day or 2.

The RG11 can apparently discern drop sizes somewhat. That's another thing I am studying. Anyway, in this afternoon's/evening's rain, interpolating some very rough data, I estimate that it takes about 250 average sized drops to equal 0.01" of rain. I emphasize, very rough.

So, if you didn't sprinkle enough water, it would not have registered a hundredth. In drop counter and ten-thousandth mode, they are very sensitive.

A couple things I am looking at...

1) using 2 RG11s to estimate drop size and therefore how hard it is raining (mist/drizzle/rain)

2) Using drop counter or 0.0001" mode to get a quicker qualitative rain rate that waiting for 0.01" tipping bucket tips. Some of you may remember my experiments with my acoustic disdrometer.
« Last Edit: October 28, 2016, 12:55:27 AM by SLOweather »

Offline kmahler

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Re: Starting to experiment
« Reply #2 on: October 28, 2016, 01:02:38 AM »
What mode is your RG11 in? 0.01" tipping bucket emulator?

So, if you didn't sprinkle enough water, it would not have registered a hundredth. In drop counter and ten-thousandth mode, they are very sensitive.


Yes, I have it in tipping bucket emulation with a 0.01" bucket. I'm fairly certain I put enough droplets on it to equal a few bucket dumps. But, I had trouble simulating small droplets like rain. That being said, if it didn't read what I was putting on it then it would malfunction in a downpour. I'm going to keep playing with it. Please keep me posted on your experiments. I can see a lot of practical uses for this sensor even if it's not accurate. Just using it in "It's raining" mode has a lot of practical uses.
Kevin Mahler
Skywarn Storm Spotter, AKQ3785
CWOP AV286
73 de KO4JY