Author Topic: Rainwise 111 easy calibrate without calibrator  (Read 431 times)

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Offline ValentineWeather

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Rainwise 111 easy calibrate without calibrator
« on: July 13, 2018, 08:29:42 PM »
More are switching over who own Davis Stations as stand alone so I tested this method and it works. Dead on today after double checking with calibrator (119 tips was goal) on 2 different Rainwise gauges and both came in at 119.   No fancy Novalynx calibrator needed. One gauge got accidentally moved the other I just ran through steps to double check tweaking slightly.

Once gauge is mounted and leveled, I like using the level across like image shows it's the most ridged area and very near the tipping buckets.  Leveling the top of gauge has mixed results at best it's the base we need level primarily with direction buckets tip.

I use a medicine syringe and 8 ml of water per tip and calibrate each bucket turning screws. When filling syringe start at 9 or 10ml instead exactly 8ml so you don't push air out prematurely at end and tip bucket.

This is a quick and simple field calibration at around 4"-4.4" per hour rate.
Have fun...

« Last Edit: July 15, 2018, 06:32:06 AM by ValentineWeather »
Randy

Offline CW2274

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Re: Rainwise 111 easy calibrate without calibrator
« Reply #1 on: July 13, 2018, 08:52:10 PM »
I use a medicine dropper and 8 ml of water per tip and calibrate each bucket turning screws.
This is what I did before using my milk jug so as to get each spoon as equal volume as possible. Then I turned both screw exactly the same amount up or down in degrees to fine tune.

Offline ValentineWeather

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Re: Rainwise 111 easy calibrate without calibrator
« Reply #2 on: July 13, 2018, 09:00:49 PM »
Works really well. I just used the calibrator to double check and confident enough to say go with 8ml per tip for good calibration.
Randy

Offline JudinNorman

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Re: Rainwise 111 easy calibrate without calibrator
« Reply #3 on: July 14, 2018, 11:12:31 AM »
The rainwise gauge needs adjustment as well out of box like the Davis tipper?

Offline ValentineWeather

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Re: Rainwise 111 easy calibrate without calibrator
« Reply #4 on: July 14, 2018, 11:59:39 AM »
The rainwise gauge needs adjustment as well out of box like the Davis tipper?

It's been so long since I tried a stock gauge but yes Rainwise gauges were closer out of box but not good enough.
I had the calibrator shortly after I purchased my first Rainwise.  The 8ml per tip is what happened to be what calibrator said to use after doing several full calibrations.
 
There may be some in areas like Florida, Mississippi where heavy downpours are common, 7.9ml may work better but for midwest plains 8ml works well. My Davis console says when doing full calibration (takes 20 min) rain rate is 4.1 to 4.6 inches per hour at 8ml.
Randy

Offline JudinNorman

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Re: Rainwise 111 easy calibrate without calibrator
« Reply #5 on: July 14, 2018, 03:12:50 PM »
Is it possible for each bucket to tip the same? Just did a few tips on mine from factory setting. One side would tip 7.5 to 8.5 ml, other 8.5 to 9.5 ml. Never the same amount each tip. Looks like even cleaned buckets and level gauge the water retention after tip isn't the same each time so with water clinging to the tipped bucket that would add weight needed to tip the high bucket.
My Rainwise lags cocorahs gauge. For spring/summer to date Rainwise caught 96% of Cocorahs. Many times the Rainwise is only .01 off, I have contributed that to the wetting of gauges differently or not quite a full bucket to tip. But if one has many light rainfalls those .01's add up.
Yesterday for example had few periods of showers when gauge funnels would dry in between showers, Coco showed .56 while Rainwise total was .51
Last week a steady consistent rainfall with both gauges showed 1.07

Offline CW2274

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Re: Rainwise 111 easy calibrate without calibrator
« Reply #6 on: July 14, 2018, 04:27:58 PM »
The rainwise gauge needs adjustment as well out of box like the Davis tipper?
Rainwise claims all their tippers are hand calibrated to an accuracy of 2% at I think a 2" per hour rate.

Offline ValentineWeather

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Re: Rainwise 111 easy calibrate without calibrator
« Reply #7 on: July 14, 2018, 04:34:43 PM »
Is it possible for each bucket to tip the same? Just did a few tips on mine from factory setting. One side would tip 7.5 to 8.5 ml, other 8.5 to 9.5 ml. Never the same amount each tip. Looks like even cleaned buckets and level gauge the water retention after tip isn't the same each time so with water clinging to the tipped bucket that would add weight needed to tip the high bucket.
My Rainwise lags cocorahs gauge. For spring/summer to date Rainwise caught 96% of Cocorahs. Many times the Rainwise is only .01 off, I have contributed that to the wetting of gauges differently or not quite a full bucket to tip. But if one has many light rainfalls those .01's add up.
Yesterday for example had few periods of showers when gauge funnels would dry in between showers, Coco showed .56 while Rainwise total was .51
Last week a steady consistent rainfall with both gauges showed 1.07

They should be the same provided you are level. Just turn the screws and get both at 8ml and you will be wearing a  :-)  next time it rains. 
Randy

Offline ValentineWeather

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Re: Rainwise 111 easy calibrate without calibrator
« Reply #8 on: July 14, 2018, 09:56:27 PM »
JudinNorman are you saying buckets tip differently each time? Never seen that before. I fill syringe to 10ml making sure air is out pull plunger down slightly and check level again. If short push plunger clearing dropper and start over. You can't add if short.
Slow down to single drops toward end before it tips you should have 2ml water left. It may take a little practice but it works well.
« Last Edit: July 15, 2018, 06:33:10 AM by ValentineWeather »
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Offline JudinNorman

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Re: Rainwise 111 easy calibrate without calibrator
« Reply #9 on: July 14, 2018, 10:27:31 PM »
JudinNorman are you saying buckets tip differently each time? Never seen that before. I fill dropper to 10ml making sure air is out pull plunger down slightly and check level again. If short push plunger clearing dropper and start over. You can't add if short.
Slow down to single drops toward end before it tips you should have 2ml water left. It may take a little practice but it works well.

That's correct. I notice the amount of water retention after the bucket tips isn't consistent which I assume would add weight to the bucket resting on screw which therefore would require more or less water to tip next bucket. There could be a ml stuck to the tipped bucket.

Do you guys dry the bucket after each tip?  Otherwise I have little idea how to control the water retention after each bucket tip. And during a rain event the tipped bucket will retain a bit anyways. Or maybe rain water flows off bucket more so than tap water.


Offline kcidwx

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Re: Rainwise 111 easy calibrate without calibrator
« Reply #10 on: July 14, 2018, 10:48:47 PM »
It's doing that because there's no water repellency on the spoons. There are products out there that are plastic safe that you can apply that will help to roll the water off the spoon.
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Offline ValentineWeather

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Re: Rainwise 111 easy calibrate without calibrator
« Reply #11 on: July 15, 2018, 06:49:43 AM »
Never noticed that amount of water staying in tipper and not able to get repeats. Issue would be the same with calibrator or even rainfall meaning gauge is crap with no repeatability if that was the case. 
I always wet the tippers before starting flip them back and forth a few times so you want a normal amount of water clinging to tipper.
I use a 10ml medicine syringe has larger opening not dropper I corrected the term dropper in top post.

I have 3 rainwise gauges and 1 Texas electronics in service at 3 different locations and all calibrate well with good repeatability.
It does take a little practice with dropper however if you push a large amount of water and tip early just do it again.
I go really slow as I get close to tipping somewhere around 6ml mark its one drop at a time toward back of tipper of course you don't want to frontload it and cause early tip that's just common sense. 

Takes about 1 minutes from that point slowing way down and finally tipping, sometimes you wonder is it going to tip.  That's where a little practice comes in.
Maybe this is harder than I thought, because I've been doing it so long it's just second nature and forgot there is a technique to it.
« Last Edit: July 15, 2018, 06:56:04 AM by ValentineWeather »
Randy