Topic: Barani: too good to be true...

[Jasper3012]

A colleague from the Netherlands is already testing against i.a. Barani. The new shield tested at meteodrenthe seems to be more resistant to rays from the side like Barani.

https://blog.meteodrenthe.nl/2024/07/29/unboxing-the-siapmicros-smart-cellino-radiation-shield/

https://www.siapmicros.com/en/smart-cellino-il-nuovo-schermo-di-riferimento-nella-misure-di-temperatura-e-umidita-dellaria/

Tbh it’s really hard to draw any conclusions from that graph because I’ve got some trees causing intermittent shading on the shields around that time of day. What you are seeing there is the Barani in the sun and the Siap+Micros just inside the shade.

Could you maybe make a table with the daily min, max and avg temp for both the Barani MS Pro and the Cellino shield? Interested in seeing the results.

[Meteorology fan]

Today was the worst day for Barani this year due to the high weather and weak wind. At times it overheated by as much as 1.5 degrees with the morning sun and low wind. The final reading on the Sensirion SHT35 was 31.5°C in the Barani Ms Pro III, while the Davis FARS24H was only 30.8°C. The Stevenson Screnn showed 30.6°C outside the city, while in the city it was 31°C 500 m from me in a sunny spot like mine.

[Jasper3012]

Measured an error of 2.1C tonight 30 min before sunset, with clear sky and virtually no wind (see graphs). Biggest error I've recorded so far, no impact on min/max but significant nonetheless.

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[Meteorology fan]

There have been a few difficult days at my place recently, when the difference between maxima reached as much as 0.7°C. Barani had a problem when the wind was weak all day and overheated notoriously. Stevenson's surrounding cages were more resistant to this. Below are the data from the chart. I'll impose a graph at my leisure sometime. There were times when it shone from the side that Barani showed nearly 1.5 degrees more than Davis FARS24H, which is an unacceptable error.

[tobyportugal]

Measured an error of 2.1C tonight 30 min before sunset, with clear sky and virtually no wind (see graphs). Biggest error I've recorded so far, no impact on min/max but significant nonetheless.

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Hello,
Where is your anemometer?
I can't see it on the photo you posted yesterday on MNW.

[Jasper3012]

I took that pic looking toward the north, when the anem was to the south of where I was standing. I moved it further away from the corn field now, as I was seeing an influence on the speeds. It’s about 30 m from the shields, 60 m from the corn and at a height of 5 m. I need to stabilize it a bit more with extra cables for the stronger winds to come, but it doesn’t move in light to moderate wind.

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[tobyportugal]

I think that with a location like yours, if you put an anemometer in the centre of your shelters, you'll be more accurate.
And that's what I'll be doing in Gembloux if the Barani and Co ‘Belgium’ project comes to fruition.
With a WS68 you get wind and radiation (not as accurate as a real pyro).
The WS68 controlled by GW1xxx with API 1 min requests.
For your information, I successfully tested the GW1xxx on a solar installation for the Italians. It ran for weeks without a hitch.
https://shop.ecowitt.com/collections/sensor-array/products/ws68
https://shop.ecowitt.com/products/gw1100?variant=41418887987362

If you add this: https://www.suncalc.org/#/39.5324,-8.929,17/2024.08.27/13:15/324.0/2

You have everything you need to draw ‘scientific’ conclusions.
 

[Jasper3012]

You mean that I should put it at the height of the shields themselves? I want to know the official wind speed (measured at 10 m), so I need to place it as high as I can and then use a formula to convert it to the 10 m value. It’s not perfect, but it’s the best I can do there for now.

[tobyportugal]

As part of a study of shelter behaviour, it's what happens in the shelters that's important. The formula remains theoretical and cannot adapt to the real environment.
I think you need to review the assembly of your 2 shelters, there are some shadows that you can easily resolve by moving the shelters slightly apart and then up again.
Just a personal opinion. 
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[Jasper3012]

The shadows you point out are cast by the equipment itself, so obviously there’s nothing we can do about that 😂 And yes, but a measurement at 5 m can quite accurately be converted to 10 m, especially in an open environment. It’s not the same as converting a wind speed value measured at 2 m in between buildings to the standard height of 10 m, obviously you can’t do that.

[tobyportugal]

If your FARS is due SOUTH (I don't think so), your Barani is not.
There's already a problem here.
Under the FARS you have shade, so the air isn't as hot...
Why would you put a radiant shelter under a FARS?
With a simple L, the problem is solved.
I have one that gives an offset of 60cm, so 120cm between 2 south-facing shelters.
If I had a site as good as yours, I'd try to make the most of it.
Opinion, not criticism. 
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[Jasper3012]

This is at the station and looking east. The rectangle you drew under the FARS and toward the ground is actually just the dark pole itself (it's a dark green) and the slight shade to the right of it is that pole casting shade on the wooden pole a few metres behind it. The middle rectangle is the "console" casting shade on its supporting pole and the shade on the FARS itself is obviously due to the solar panel. I am a bit of a perfectionist myself but I do think we're taking it a bit too far here 

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[bianconero57]

  well you'll have to review the step when you receive your new toy... anyway i say that 

[Meteorology fan]

bianconero57 - Have you ordered anything from FARS24H Apogee TS100 or Davis FARS24H?

[bianconero57]

bianconero57 - Have you ordered anything from FARS24H Apogee TS100 or Davis FARS24H?

  the TS-100 still on sale = abandoned project - i don't have the FARS Davis but YES the new FARS Barani version 

[Meteorology fan]

Barani FARS is a poor choice. Air drawn from warm plates, no FARS at night. The Davis FARS24 in this field is better, so is the Apogee TS100. This helix in Barani has even more disadvantages than the top multi-plate covers.

[bianconero57]

Barani FARS is a poor choice. Air drawn from warm plates, no FARS at night. The Davis FARS24 in this field is better, so is the Apogee TS100. This helix in Barani has even more disadvantages than the top multi-plate covers.

  strictly personal opinion
my Apogee is still relevant if interested possibly 
have a nice day

edit : and i also have some ecowitt mounted sht45_EP for sale if anyone here is interested 

[Meteorology fan]

It's physics. A shield that pulls air in from the side will never be as good as pulling air out from underneath like the Apogee TS100 and Davis FARS24H. I have access to the Apogee TS100 in Poland at a good price.

[Jasper3012]

FARS at night isn't necessary with the Barani, the avg min on the Barani over a longer period is less than 0.1C milder than on the Davis. The biggest difference I've ever recorded is a 0.4C difference in the recorded min. The Barani does sometimes lag behind more than this 0.4C value but this is always a temporary thing.

[hmderek]

This is at the station and looking east. The rectangle you drew under the FARS and toward the ground is actually just the dark pole itself (it's a dark green) and the slight shade to the right of it is that pole casting shade on the wooden pole a few metres behind it. The middle rectangle is the "console" casting shade on its supporting pole and the shade on the FARS itself is obviously due to the solar panel. I am a bit of a perfectionist myself but I do think we're taking it a bit too far here 

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Have I mentioned yet I love your spot? ^_^

[Jasper3012]

This is at the station and looking east. The rectangle you drew under the FARS and toward the ground is actually just the dark pole itself (it's a dark green) and the slight shade to the right of it is that pole casting shade on the wooden pole a few metres behind it. The middle rectangle is the "console" casting shade on its supporting pole and the shade on the FARS itself is obviously due to the solar panel. I am a bit of a perfectionist myself but I do think we're taking it a bit too far here 

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Have I mentioned yet I love your spot? ^_^

Yes, you have It's a very good spot indeed, can't do better than that here.

[hmderek]

When talking about daily max temps of ventilated vs passive systems, this is also something that can happen. The TS-100 could show a daily max over 0,4 degrees higher than the passive Barani due to stronger responsiveness to temperature changes.

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[Jasper3012]

Your graph is actually a perfect example of a better response time, it goes higher than the Barani during peaks and lower than the Barani during drops. What I’ve often been seeing isn’t that though (at least not fully explained by it), I’ve often just recorded the Davis being a steady 0.3C warmer than the Barani during sun and wind, with not really a better response time but just a steady overheating. Graph below from a few days ago shows this during the afternoon, you don’t see a more erratic curve due to a better response time on the Davis (the brown line), but rather just a constant 0.2-0.4C warmer.

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[Meteorology fan]

August is full of days with high weather and light winds in Poland. These conditions do not serve the Barani Meteoshield Pro III shield. On several occasions in the past few days, Barani has overheated by more than 1 degree. In the mornings even 1.5 degrees, afternoons and evenings are sometimes difficult with errors from solar radiation reaching more than 1.5 degrees. The sun angle in August is lower than in July, as can be seen from the frequent Ms Pro III errors in the Polish climate. In autumn and winter with low winds it can be even worse.

Several days in a row the t-max was higher on the Ms Pro III than on the Davis FARS24H.

[hmderek]

Your graph is actually a perfect example of a better response time, it goes higher than the Barani during peaks and lower than the Barani during drops. What I’ve often been seeing isn’t that though (at least not fully explained by it), I’ve often just recorded the Davis being a steady 0.3C warmer than the Barani during sun and wind, with not really a better response time but just a steady overheating. Graph below from a few days ago shows this during the afternoon, you don’t see a more erratic curve due to a better response time on the Davis (the brown line), but rather just a constant 0.2-0.4C warmer.

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Am I correct to assume that both those sensors are standard Davis issue SHT31s?