Author Topic: First Tip in Rain Gauge  (Read 942 times)

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benay ra'am

• Senior Contributor
• Posts: 152
First Tip in Rain Gauge
« on: September 12, 2017, 09:31:30 PM »
Why is that not counted? I had a few rain events and the Rain count in my Davis is always .01 behind the CoCoRaHS. I know .01 is nothing to biotch about, just curious is all. I'm thrilled that the Davis is in lock step with the CoCoRaHS............

CoCoRaHS: NC-JH-80

WheatonRon

• Forecaster
• Posts: 754
Re: First Tip in Rain Gauge
« Reply #1 on: September 12, 2017, 09:58:41 PM »
Why is that not counted? I had a few rain events and the Rain count in my Davis is always .01 behind the CoCoRaHS. I know .01 is nothing to biotch about, just curious is all. I'm thrilled that the Davis is in lock step with the CoCoRaHS............

I don't have an answer but do have a question for you. When you say Davis is always .01 less than the CoCo gauge that doesn't mean anything without some context. Are you measuring a heavy rain fall so you are talking about 1.25 vs. 1.24, OR are you talking about a minor rain, say, .10 vs. .09? One is a 10% error the other is less than an 1% error.
« Last Edit: September 12, 2017, 10:01:35 PM by WheatonRon »
Davis VP2 with Daytime FARS, SHT31 (2 complete systems-1 for uploading to the internet, the other system for test and play); Rainwise 111; CWOP--CW5020; WU--KILWHEAT17; CoCoRaHS--IL-DP-132

CW2274

• Forecaster
• Posts: 3080
Re: First Tip in Rain Gauge
« Reply #2 on: September 12, 2017, 09:59:53 PM »
Why is that not counted?
What is "that"? Your first tip? It certainly should. If one counts, all should count. Are you saying the VP2 is behind 0.01" compared to the Coco because first didn't count? Please elaborate.
Davis Wireless VP2 SHT31 24hr 67CFM FARS
RW Tipper w/ CoCoRaHS

dalecoy

• Forecaster
• Posts: 5979
Re: First Tip in Rain Gauge
« Reply #3 on: September 12, 2017, 10:14:12 PM »
Have you actually done that test manually?  After a quiet period, tipped the rain bucket once and seen that it was not shown in the data?

Or are you assuming, based on some other information?

Or are you just trolling for an argument?

benay ra'am

• Senior Contributor
• Posts: 152
Re: First Tip in Rain Gauge
« Reply #4 on: September 12, 2017, 10:15:47 PM »
Does not matter heavy or light Rain, CoCoRaHS at .01, Davis 0.00, CoCo .02 Davis .01 and up to the final count. Six rain events always .01 behind. That's why I thought the first tip was not counted. Not a Big deal for me. I can't prove it with data as I just ordered the Data Logger a few hours ago.

CoCoRaHS: NC-JH-80

benay ra'am

• Senior Contributor
• Posts: 152
Re: First Tip in Rain Gauge
« Reply #5 on: September 12, 2017, 10:18:16 PM »
Have you actually done that test manually?  After a quiet period, tipped the rain bucket once and seen that it was not shown in the data?

Or are you assuming, based on some other information?

Or are you just trolling for an argument?

Actually I did, I did one tip and nothing, on the second tip I got .01. This is when I had  the ISS on my bench. I thought nothing of it at the time.......

« Last Edit: September 12, 2017, 10:27:24 PM by benay ra'am »

CoCoRaHS: NC-JH-80

dalecoy

• Forecaster
• Posts: 5979
Re: First Tip in Rain Gauge
« Reply #6 on: September 12, 2017, 10:23:40 PM »
In that case, it's a very interesting question.

Mattk

• Forecaster
• Posts: 467
Re: First Tip in Rain Gauge
« Reply #7 on: September 12, 2017, 11:02:40 PM »
is this associated with the trigger for a rain event which raises the flag after 0.4mm?

Or is this a 0.2mm gauge set to imperial? 1 tip of a 0.2mm tipper is less than 0.025mm or 0.01", 2 tips would be 0.4mm indicating at least 0.01" but not enough to register 0.02" (~ 0.51mm)

benay ra'am

• Senior Contributor
• Posts: 152
Re: First Tip in Rain Gauge
« Reply #8 on: September 13, 2017, 06:27:46 AM »
is this associated with the trigger for a rain event which raises the flag after 0.4mm?

Or is this a 0.2mm gauge set to imperial? 1 tip of a 0.2mm tipper is less than 0.025mm or 0.01", 2 tips would be 0.4mm indicating at least 0.01" but not enough to register 0.02" (~ 0.51mm)

AFAIK it is set up as Imperial right from Davis. There is a .01 Placard right next to the tipping buckets.

CoCoRaHS: NC-JH-80

archae86

• Contributor
• Posts: 137
Re: First Tip in Rain Gauge
« Reply #9 on: September 13, 2017, 08:37:11 AM »
Which display output variable are you looking at? The Davis definition of Storm Total means that the storm total display continues to read zero until the second tip. On the other hand the umbrella appears on the console immediately after the first tip and the various other (not storm) totals also update immediately. Is yours doing something different?

dalecoy

• Forecaster
• Posts: 5979
Re: First Tip in Rain Gauge
« Reply #10 on: September 13, 2017, 11:26:23 AM »
From the console manual,

Daily Rain
Press RAINDAY to display the rain accumulated since 12 midnight. Any
rain accumulated in the last 24 hours displays in the ticker at the bottom of
the screen.

Rain Storm
Rain Storm displays the rain total of the last rain event. It takes two tips of the rain
bucket to begin a storm event and 24 hours without rain to end a storm event.
Press RAINDAY to toggle between the daily rain total and the Rain Storm total. Rain
accumulation may be displayed as either millimeters (mm) or inches (in).

rdsman

• Senior Contributor
• Posts: 176
Re: First Tip in Rain Gauge
« Reply #11 on: September 13, 2017, 11:28:45 AM »
For what it's worth, coming from the VUE ISS, pay attention to Byte 2 (8x) in the E0 message.

Initial power up:

Index: 01  Packet: E0  00  59  80  01  00  08  5D  FF  FF  RSSI: -55  Error: -1

(Console displays 0.00 in)

One tip:

Index: 06  Packet: E0  00  59  81  03  00  59  0F  FF  FF  RSSI: -59  Error: 0

(Console displays 0.00 in)

Two tips:

Index: 43  Packet: E0  00  59  82  01  00  66  3D  FF  FF  RSSI: -53  Error: 0

(Console displays 0.01 in)

Three tips:

Index: 27  Packet: E0  00  59  83  03  00  37  6F  FF  FF  RSSI: -61  Error: 0

(Console displays 0.02 in)

Four tips:

Index: 34  Packet: E0  00  59  84  01  00  D4  9D  FF  FF  RSSI: -65  Error: 0

(Console displays 0.03 in)

And so on.............

Ray

92merc

• BismarckWeather.net
• Forecaster
• Posts: 570
• BismarckWeather.net
Re: First Tip in Rain Gauge
« Reply #12 on: September 13, 2017, 02:40:27 PM »
Actually, you're most likely missing the last tip.  The little "cup" isn't quite heavy enough to actually tip over and give that last .01.

Unfortunately, that's the nature of the beast when you deal with a mechanical device like this.  Any "self emptying" type device might miss a little bit.  Due to dribbles, wind, not quite enough to add up to .01.  A funnel will catch everything.  Including bugs once in awhile.
http://www.BismarckWeather.net
Davis VP2, Cumulus, Blitzortung, Bloomsky, Saratoga Scripts

Mattk

• Forecaster
• Posts: 467
Re: First Tip in Rain Gauge
« Reply #13 on: September 13, 2017, 04:27:18 PM »
is this associated with the trigger for a rain event which raises the flag after 0.4mm?

Or is this a 0.2mm gauge set to imperial? 1 tip of a 0.2mm tipper is less than 0.025mm or 0.01", 2 tips would be 0.4mm indicating at least 0.01" but not enough to register 0.02" (~ 0.51mm)

AFAIK it is set up as Imperial right from Davis. There is a .01 Placard right next to the tipping buckets.

What does the counter weight on the bottom of the tipper look like, round section or oval section?

benay ra'am

• Senior Contributor
• Posts: 152
Re: First Tip in Rain Gauge
« Reply #14 on: September 13, 2017, 06:03:30 PM »
Well, I just got home from work, checked to make sure I had 0.00, went out and tripped the bucket once, checked my console and I had 0.01 with the umbrella. Man I feel like a doddering old fool Should have done that before I posted . 0.01 off from the CoCo at different rain events is excellent in my book ..............

Thanks for everyone with helping out with a non-problem.
« Last Edit: September 13, 2017, 06:05:21 PM by benay ra'am »

CoCoRaHS: NC-JH-80

CW2274

• Forecaster
• Posts: 3080
Re: First Tip in Rain Gauge
« Reply #15 on: September 13, 2017, 06:14:40 PM »
0.01 off from the CoCo at different rain events is excellent in my book ..............
It is as long as your not talking less than a tenth or so. If you're talking .50" or more, that's very respectable, especially for the Davis tipper, worst part of the ISS (well, the fan's too).
Davis Wireless VP2 SHT31 24hr 67CFM FARS
RW Tipper w/ CoCoRaHS

benay ra'am

• Senior Contributor
• Posts: 152
Re: First Tip in Rain Gauge
« Reply #16 on: September 13, 2017, 08:14:23 PM »
0.01 off from the CoCo at different rain events is excellent in my book ..............
It is as long as your not talking less than a tenth or so. If you're talking .50" or more, that's very respectable, especially for the Davis tipper, worst part of the ISS (well, the fan's too).

CoCo=3.83 Davis=3.82, that was with a steady Rain with light wind or 4mph and lower, that was the day before I posted the Images here. From yesterday CoCo= 0.62 Davis=0.61 same slow steady rain with light wind for the most part. As for the Fan, I have a box full of Computer Case and Heat Sink Fans I can play around with.............

CoCoRaHS: NC-JH-80

CW2274

• Forecaster
• Posts: 3080
Re: First Tip in Rain Gauge
« Reply #17 on: September 13, 2017, 08:43:00 PM »
0.01 off from the CoCo at different rain events is excellent in my book ..............
It is as long as your not talking less than a tenth or so. If you're talking .50" or more, that's very respectable, especially for the Davis tipper, worst part of the ISS (well, the fan's too).

CoCo=3.83 Davis=3.82, that was with a steady Rain with light wind or 4mph and lower, that was the day before I posted the Images here. From yesterday CoCo= 0.62 Davis=0.61 same slow steady rain with light wind for the most part.
You either have the best luck or most accurate tipper of all time. Amazing....
Davis Wireless VP2 SHT31 24hr 67CFM FARS
RW Tipper w/ CoCoRaHS

benay ra'am

• Senior Contributor
• Posts: 152
Re: First Tip in Rain Gauge
« Reply #18 on: September 13, 2017, 09:09:26 PM »
0.01 off from the CoCo at different rain events is excellent in my book ..............
It is as long as your not talking less than a tenth or so. If you're talking .50" or more, that's very respectable, especially for the Davis tipper, worst part of the ISS (well, the fan's too).

CoCo=3.83 Davis=3.82, that was with a steady Rain with light wind or 4mph and lower, that was the day before I posted the Images here. From yesterday CoCo= 0.62 Davis=0.61 same slow steady rain with light wind for the most part.
You either have the best luck or most accurate tipper of all time. Amazing....

No, just the perfect Rain, bet that will change with a heavy down pour and/or heavy wind. (My Acurite over reported by 0.40 at 4.23.) Could also be the CoCo is not located where it should be, closer to the ground and by it self or I did get a real good tipper and someone at Davis went the extra mile with the Calibration or I lucked out like you said.
« Last Edit: September 13, 2017, 09:14:13 PM by benay ra'am »

CoCoRaHS: NC-JH-80

benay ra'am

• Senior Contributor
• Posts: 152
Re: First Tip in Rain Gauge
« Reply #19 on: September 21, 2017, 06:43:43 PM »
A little update, yesterday I had a rain event. The rate of Rain was 4.17"Hr ( As reported on Cumulus ) with a Precip of .51" in the CoCo and .49" reported on the Davis. Today we had a bigger rain event. The rain Rate 8.60"Hr ( As reported on Cumulus ) with a Precip of .94" in the CoCo and .92" reported on the Davis. I'm pretty happy with that and I'm not going to fiddle fart with the Calibration

BTY: I installed WLUSB ( In Serial Port Mode ) and Cumulus on a old Dell 17" Studio Laptop running Vista SP1 and they are both working as advertised, no problems setting either one up. I don't know at this time if I'm going to send data to Wunderground, but I will send to CWOP once I know the laptop will run 24/7 and try out WD too. Baby steps, Baby steps.................

CoCoRaHS: NC-JH-80