Topic: Wind Speed Calculation and reporting of the WS-2000

[dunc1ca]

I decided to see how the WS-2000 ACTUALLY reports wind speed sustained and gusts.

First, according to the FAQ:
https://ambientweather.net/help/how-is-the-wind-speed-and-wind-gust-calculated-in-the-ws-2000-weather-station/

"The sensor array updates wind speed and direction once per second and then calculates the 16 sample average as wind speed and the peak or maximum wind speed in the 16 second update period as gust."

I recorded each 16-second update as they appeared on the WS-2000 display.
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I have my history set to 1 minute on the WS-2000 settings.  The history shows the most recent data point each minute.  You can see each report on column B highlighted
WU and AW dashboard each have 5-minute data points.  It appears to merely pick the most recent data point as seen in the highlighted chiclet columns A and C.
The 10 Min Avg appears to update on the WS-2000 every 80 or 96 seconds.  My own 10-minute average (actually 9min 52sec) shows a discrepancy.  I'm not sure why, but I did not factor in direction and do a vector average.
Also, at the time 14:32:26, there is a gust of 11.2 km/h on the display.  Since that occurred between any of the chiclets, it does not show up on WU, AW dashboard nor the WS-2000 display unit's history.  My Max Daily Gust is 22.0 km/h.  Presumably, it would show up there regardless if it had exceeded this value.

Another note, according to the Automated Surface Observing System User's Guide (Section 3.2.2.2a):
https://www.weather.gov/media/asos/aum-toc.pdf

"Once every 5 seconds, the ASOS compares the highest gust stored in memory for the past 10 minutes with the current 2-minute average wind speed. If the difference between the two is 3 knots or more, the current reported wind speed is greater than 2 knots, and the highest gust exceeds the minimum 5-second wind speed in the past 10 minutes by 10 knots or more, then the highest gust stored in memory is designated as the reportable gust."

Basically, it should be 2 minutes of averaging for sustained winds and 10 minutes peak instantaneous for gusts.  Currently, the WS-2000 does 16 seconds for both.

[mikemm]

 If you want to know how the Fine Offset WH24 sensor module, then I posted an analysis of how it REALLY measures wind speed in this post:  http://www.wxforum.net/index.php?PHPSESSID=4b85ccb2b5db5d854f6c78beee1f62d7&topic=28713.msg278935#msg278935

Bottom line: this common sensor module resold by everyone is very approximate in terms of wind speed sensing; it effectively ignores measuring wind speed for 12 hours out of 24 hours since it ignores all wind sensing in the first 8 seconds of a 16 second reporting interval:

    Gust Windspeed:  resolution and minimum value 1.1 meters/sec = 3.98 km/h = 2.46 MPH (one revolution of the anemometer); measured as the largest quantity of revolutions found in any one second in the final 8 seconds of the 16 second reporting interval
    Average Windspeed: resolution and minimum value 0.14 meters/sec = 0.504 km/h = 0.3 MPH (1/8 revolution of the anemometer); measured as the quantity of revolutions divided by 8 found ONLY in the final 8 seconds of the 16 second reporting interval

Also note, this limitation has nothing to do with your display console, or with the IPObserver module, or with the MeteoBridge module.  This is a limitation in the outside sensor module itself, and cannot be "fixed" by software or firmware.

[galfert]

I'm pretty sure that the Osprey WH65 sensor array is a big improvement over the WH24. Just wanted to let people know that might be confussued reading the prior post that the WH24 is not what is included with the WS-2000 nor the WS-2902A as they have the newer Osprey WH65.

[kbellis]

  Stephen Rose and others reported some differences between the two sensors:
https://github.com/merbanan/rtl_433/issues/844

I'm pretty sure that the Osprey WH65 sensor array is a big improvement over the WH24. Just wanted to let people know that might be confussued reading the prior post that the WH24 is not what is included with the WS-2000 nor the WS-2902A as they have the newer Osprey WH65.

[StephenR0]

If you want to know how the Fine Offset WH24 sensor module, then I posted an analysis of how it REALLY measures wind speed in this post:  http://www.wxforum.net/index.php?PHPSESSID=4b85ccb2b5db5d854f6c78beee1f62d7&topic=28713.msg278935#msg278935

Some time back, I noticed your very interesting post.  I was interested to see if the WH65B behaved in a similar manner.  When I performed the same experiments with the WH65B, it was clear that it was using the whole 16 seconds between packets for wind speed.  Thank you for your interesting experiment.

[kbellis]

Thanks for this information Stephen!

FWIW - The ECOWITT WS68 Wireless Solar Powered Anemometer with Light & UV Sensor has been reported to work with the Ambient Weather WS-2000 Display Tablet, though it's uncertain if that ability will be tolerated between competing Fine Offset resellers.

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A month or so ago, I asked,"Is the radio frequency range of the anemometer the same in all directions, e.g., overhead and above the display console?"

The unsatisfactory answer eventually followed, "Hi, sorry for the delay due to holiday.
The radio frequency range of the anemometer to the display console should be within 300ft/100m (open areas). "

Radio signal patterns are three dimensional, and I'm still curious how well the receiver being directly beneath the transmitter will operate.

[galfert]

Kelly,

If you are referring to this Amazon review:
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That review is only talking about the WH31B sensor being compatible with the WS-2000 display tablet console. Even though the link you provided is for the Ecowitt anemometer, on Amazon it shares the same listing as the other Ecowitt sensors. So the reviews are from any of those sensors and you need to read the details in the reviews to figure out what exact product the review is talking about. I find this confusion happens a lot with Amazon reviews when some related products are grouped together. I'm not saying you might be right or wrong that the anemometer does work with the WS-2000 display tablet console. I just don't see the proof yet. The anemometer will work with Ecowitt's white display console though as it is part of the HP3501 kit.
https://www.amazon.com/ECOWITT-Wireless-Anemometer-Self-Emptying-Collector/dp/B07MZ3YV64/

[kbellis]

Ah, I see the obfuscation! Thanks for pointing this out.

Mistakenly I read the review on the product page, thinking it was applicable to the product. Amazon appears to be allowing this unethical practice by the reseller; shame on them both.

[galfert]

I don't see it so much as unethical on the seller. The seller just wants to be able to group products that are related like accessories. It helps people know that these grouped items work together so they don't have to wonder if the parts are compatible. And Amazon does provide indication of what specific item is being reviewed. If you look at the descriptor called "color" that indicates which specific item the reviewer bought and is reviewing. Still perhaps Amazon should then only show the reviews for the pertinent item or at least make a bit more prevalent. Also the use of the "color" needs updating. I can see how originally it was intended for the seller to sell more than one item of different colors. But perhaps it is the sellers fault because the grouping should only be used when it is the same product but of a different color....and not to be used for accessories or compatible parts. But it has been like this for years. So I have no idea who really is more at fault...the seller for not sticking to the rules or Amazon for having a confusing selling platform that they don't police.

[Mandrake]

Technically for sure the WS2000/HP2550 console could support the new independent anemometer. If you look at the HP3500 and then the HP3501 you can see that former console is using the all-in-one sensor array and the HP3501 the new individual sensors. Whether there is a difference in the firmware to make this happen or if it just detects the various components is unknown.
I have asked Ecowitt about the WS2000 and the new individual sensors and it has been said that technically that it can support them though it was not stated that they can do so today.
It may require firmware changes. We do know for instance that the firmware will support the PM2.5 sensor in conjunction with the all-in-one array as it is today.