Author Topic: RG11 as a rain rate/intensity detector  (Read 2433 times)

0 Members and 1 Guest are viewing this topic.

Offline SLOweather

  • Administrator
  • Forecaster
  • *****
  • Posts: 3128
    • http://www.sloweather.com
Re: RG11 as a rain rate/intensity detector
« Reply #25 on: December 07, 2016, 10:19:01 AM »
Neat!  Basically a bell curve - normal distribution.  Now you need to correlate the drop size with rate/intensity etc.   :)

Yeah, I have some ideas like that. However, now that I have this part working, I realize that there are some inaccuracies inherent in my methods.

For one thing, the 2 RG11s are about 14 inches or 8 sensor diameters apart, which I think may cause some measuring inconsistencies I saw while watching the clicks come in. So, before it rains tomorrow, I'll move them closer together.

Then there is a potential sampling or measuring bias. Right now, I log the respective counts once a minute. However, that can be somewhere random in between emulated tipper tips, while still counting drops. I'll have to see if I can log on tipper clicks instead of time to minimize that.

And, using the standard we are all used to, the 0.01 tipper, is comparatively so long between tips next to the 0.0001" emulation, I'm not sure how well it would correlate intensity.

I do have a third RG11. I might set it up as a 0.001" tipper for fun...

Offline miraculon

  • Sunrise Side Weather
  • Forecaster
  • *****
  • Posts: 2698
  • KE8DAF
    • Sunrise Side Weather in Rogers City MI USA
Re: RG11 as a rain rate/intensity detector
« Reply #26 on: December 07, 2016, 10:42:40 AM »
I run my RG11 in 0.001"/tip emulation mode. I have it interfaced to one of my Davis stations, originally a Temp/Hum, but configured as an ISS depending on which receiver it goes to (meteo-bridge-hubs).

I decided on the 0.001"/tip in order to get finer granularity for rain start/stop times. I considered the 0.0001"/tip but I was concerned about relay life. I these fine gradation modes, even drop counting, I would think that relay life would be a concern. I couldn't find a spec for the relay, it is probably in the millions of cycles. I still didn't want it to beat itself to death.

Greg H.




Blitzortung Stations 668, 706 - CWOP CW4114 -  CoCoRaHS MI-PI-1

Offline SLOweather

  • Administrator
  • Forecaster
  • *****
  • Posts: 3128
    • http://www.sloweather.com
Re: RG11 as a rain rate/intensity detector
« Reply #27 on: December 07, 2016, 11:12:19 AM »
Well, Greg, let's see...

Where you live get 31" of rain annual average.  With a perfect 0.0001" emulation, that would be 310,000 relay clicks a year.

For the drops/0.0001" from the storm I've been working with, that would be about 1.5 million rain drop clicks a year.

OTOH, if I recall correctly, here our average annual wind speed is about 5 mph. That's about 14 million clicks per year of a Davis anemometer. 

And, the RG11s are only $59 now. I think I paid $100 for my first one.

I think you're good to up the rates if you want, and long as you aren't running the relay close to the max spec on voltage/current. (and you're not.)

Offline PaulMy

  • Forecaster
  • *****
  • Posts: 3405
    • KomokaWeather
Re: RG11 as a rain rate/intensity detector
« Reply #28 on: December 07, 2016, 11:33:49 AM »

Quote
Hmmm, I may still have my original Visicalc disk around here somewhere...
Not in the same league as you Chris, but I do have the original Multiplan diskette and manual that I glanced at last night.  It does have a Multiplan vs. VisiCalc key comparison.  I used it in my first accounting job and did the books on it for our local municipality on my personal Commodore 64 until I was able to set up a real computer environment at work.


Paul




Offline Bushman

  • Forecaster
  • *****
  • Posts: 6309
    • Eagle Bay Weather
Re: RG11 as a rain rate/intensity detector
« Reply #29 on: December 07, 2016, 02:57:44 PM »
Anyone here ever hear of 10 Planner?

Offline kmahler

  • Senior Member
  • **
  • Posts: 54
Re: RG11 as a rain rate/intensity detector
« Reply #30 on: December 12, 2016, 10:56:58 AM »
SLOWeather,

I recall you telling me the RG-11 wasn't very accurate in tipping mode. I thought I'd share my first experience using it. I have mine running in an experimental install right now. Before the rain today it had erroneously recorded 4 bucket tips. But, since it started raining today, so far I have .15" as measured in my Stratus RG202 rain gauge. Subtracting the 4 erroneous bucket tips the RG-11 is tracking exactly the same rainfall. My Ambient Weather 2080 has recorded .20" so it's a bit over counting.

I consider the RG202 to be the Gold Standard at my location.

Just thought I'd let you know. More data to come as my experimenting continues.
Kevin Mahler
Skywarn AKQ3785
KO4JY


Offline SLOweather

  • Administrator
  • Forecaster
  • *****
  • Posts: 3128
    • http://www.sloweather.com
Re: RG11 as a rain rate/intensity detector
« Reply #31 on: December 14, 2016, 07:20:56 PM »
Cool. I have a couple of thoughts.

I got mine and started this topic back in Oct 2011. In the last 5 years they may have improved the firmware.

Second, what was the storm like? In last weekend's very light rain event, my 2 Davis, the Rainwise, and the Stratus all recorded 0.16" of rain.

However, the 0.0001" Hydreon recorded only 0.0419", the drop counter 103o drops.

We have a better storm on tap for tomorrow...


Offline kmahler

  • Senior Member
  • **
  • Posts: 54
Re: RG11 as a rain rate/intensity detector
« Reply #32 on: December 14, 2016, 11:04:30 PM »
Yeah, I thought about firmware updates too. However, I have had another rain since where the RG-11 was a bit off so maybe the storm I reference above was an anomaly in accuracy. We are expecting rain over the next couple of days so I will track it again. I'll try to capture samples with timestamps this time. I didn't have that as an option during the first storm. I have attached the graph from wunderground as reported by my WS-2080 below to give you an idea of the levels of intensity. In verbose terms it was a steady moderate rain with waves of downpours.
 [ You are not allowed to view attachments ]
Kevin Mahler
Skywarn AKQ3785
KO4JY


Offline SLOweather

  • Administrator
  • Forecaster
  • *****
  • Posts: 3128
    • http://www.sloweather.com
Re: RG11 as a rain rate/intensity detector
« Reply #33 on: December 15, 2016, 06:03:28 PM »
Right now, my 3 tippers are at 0.21", the Hydreon, tipper at 0.2838" (over reporting) and the drop counter at 1407, or 2.08 drops per 0.0001", way fatter drops than I've seen before...