Questions about Davis VP 2 Siting

[niko]

I saw those quite elaborate fence looking things people have mounted around their rain buckets.  In fact, I think they were actually a commercially made product to block "all" wind from reaching the bucket.

That's an Alter Shield.

[FarmingtonWeather]

That's an Alter Shield.

you so smart

That is one type I saw, I also saw another very similar type.  In the one case they actually had multiple rings of things similar to that.  The link gave me an idea for mine using plastic snow fence that comes in 4' widths which would be folded over in half making it 2' high so the top would be even with the top of the rain bucket, if in fact I take the rain bucket off of the ISS.

Thanks!

[niko]

I think part of the function is that the bits aren't fixed, they can swing.

[FarmingtonWeather]

I think part of the function is that the bits aren't fixed, they can swing.

got it...I wasn't comparing the Alter version to the snow fence version, I was comparing old style stick snow fence to the more modern plastic version.

I think surrounding the rain bucket with the modern snow fence material would accomplish part of the task that the Alter does.

I don't get what additional value having them able to swing provides but they must have thought there was some merit to that design, or at least they want you to think there is    I haven't seen a study on the various surrounds.  I noticed the sample AWI system now being used at airports doesn't have any kind of a surround around their bucket.

I swung by the Rainwise site to check out their rain buckets and found that they show the Alter design as an option to their setups.

Thanks

[niko]

According to Accuweather "The advantage of this [Alter] shield is that the slats do not easily accumulate snow, permitting its use on unattended gauges".

[FarmingtonWeather]

According to Accuweather "The advantage of this [Alter] shield is that the slats do not easily accumulate snow, permitting its use on unattended gauges".

Seems to me it wouldn't matter if they collected snow on them if the whole works is sitting in several feet of snow

I am contemplating a method to mount the rain bucket and temp sensor on a moveable arm such that I can go out and raise it from time to time as the snow accumulates under the sensors.

My current plan is to put in a new, taller mast instead of using the martin house pole my anemometer is on now.  Then I will add a PVC pipe a larger diameter that can slide up and down on the mast pipe and I would use a hose clamp under it I can lossen and move as necessary.  Off of that vertical PVC pipe will be two opposing horizontal arms, but not at the same height.  On arm would be lower and would have the rain bucket on it and a higher arm would have the temp sensor and ISS on it.  The cable from the anemometer would come down from above and would have a loop in it so it could be moved up and down as necessary.

Seems easy enough plan and gives me the flexibilty to raise and lower the whole works as needed.  The other added value is I can temporarily raise the arms to mow under them

Seems like an inelegant but workable plan...has anyone tried something like this?  At least those where it snows?

Lew

[FarmingtonWeather]

Hello again...

We all know the Davis ISS was designed for the simplest installation possible, disregarding optimal siting options.  Ideally all components would be independent and could be scattered around ideally like my Honeywell.  However the Honeywell's wireless distances aren' adequate for my needs.  I needed to figure out a way to get my new site sited as well as possible without buying a lot of extra stuff.  I came up with a design that I think creates a great site score and solves other problems at the same time like mowing under the bucket and dealing with snow depth.

Here is my current concept, please be as critical as possible as it is all just theoretical at this point as my Davis hasn't arrived.

Oh ya, I have already expanded the concept to change the bracket under the rain bucket to attach an Alter style wind ring which can also raise and lower with the bucket.



Thanks!

Lew

[niko]

Looks good except that's probably not a great location for the solar sensor. What I have done is to extend the solar sensor cable and mount it at the top of the mast with the anemometer (need another home made bracket).

[TNETWeather]

I would highly suggest that you try a much simpler configuration first.  After that, if you are not satisfied with the result, you could experiment etc..

I doubt you will get much of a difference in numbers if you simply place your Anemometer up on the Roof and mount your ISS as a whole on a post at 5-6ft.  No Alter style wind break, no PVC pipes (most likely will bend and sway anyway).

You are going to a lot of trouble to be perfect with what I think will end up being negligible different results from a more common simpler setup.  This is especially true when you factor in the accuracy of the instruments and issues in your area that will effect your sitting location (Unless you plan on cutting down some tree's too).

[administrator]

I think you'll find the rain gauge bracket will be unstable and you will probably suffer from false rain readings due to the gauge being buffeted by strong winds. I also think you're unlikely to be able to raise/lower the entire unit carefully enough to avoid false rain readings when you want to mow under the structure.

[aardvark]

I think he could mow under it..  use one of those string trimmers, or  since he is going with the concept  of putting in a mast, could modify the surface under it, either kill off the grass ( the misses will like that one, you can bet... talking from experience and a lot of grass seed later),  put in a drain of pebbles or pea gravel under it in a depression with something to allow the water run off.


I would wonder one thing.. will the front of the solar panel get the sunlight , be able to send the signal up to his console, that is the antenna signal spread and then what happens in snow or any environmental situation.

Finally,   will it meet NWS / NOAA/? standards for rain collections as being correct.

But it could be done.  and this advice comes from a man sitting trying to modify his website theme, listing to ABBA on his ipod and realizing it is best to hear that when the family is gone, they might think I have become fruity...

[FarmingtonWeather]

Looks good except that's probably not a great location for the solar sensor. What I have done is to extend the solar sensor cable and mount it at the top of the mast with the anemometer (need another home made bracket).

I am curious why you thought that about the solar sensor.  The sensor would be south of the pole and should never have a shadow?  is the sun different at 2' vs. 33'?

Appreciate your feedback!

Lew

[FarmingtonWeather]

I would highly suggest that you try a much simpler configuration first.  After that, if you are not satisfied with the result, you could experiment etc..

I doubt you will get much of a difference in numbers if you simply place your Anemometer up on the Roof and mount your ISS as a whole on a post at 5-6ft.  No Alter style wind break, no PVC pipes (most likely will bend and sway anyway).

You are going to a lot of trouble to be perfect with what I think will end up being negligible different results from a more common simpler setup.  This is especially true when you factor in the accuracy of the instruments and issues in your area that will effect your sitting location (Unless you plan on cutting down some tree's too).

I don't want to have to add a wireless unit to the anemometer.  The solution I propose only requires a cable from the ISS to the temp sensor, nothing else as the other cable from the anemometer to ISS is provided and is long enough.  I don't know of any other way to put one thing on the house and the other 75 ft away in the yard other than a long cable and trenching it into the ground?

I don't consider it a lot of trouble and your suggestion still leaves the issue of mowing around it?  PVC pipe is pretty sturdy if a big enough gauge is used and there isn't much sway 2' up the mast???   

I didn't say where I would mount this so trees might not be a factor.  Actually, trees are no more a factor where my current mast is than on the house...actually, there are taller trees closer to the house (and taller than the house) than where my current mast is.  I am still considering mounting this out in the field away from everything. 

The PVC pipe is cheap and stronger than I think you think   Go to the hardware store and grab some 3 or 4" PVC.  I bet you couldn't bend it.  I can't   and the time to do what I am proposing is probably less than the drawing took to make   If I thought it would take a lot of time, I wouldn't be doing it. 

I was going to initially install it on my current mast and see if the plan works, then install it on a stronger, taller mast when I see if the concept works.

Thanks for your input!

Lew

[niko]

I am curious why you thought that about the solar sensor.  The sensor would be south of the pole and should never have a shadow?  is the sun different at 2' vs. 33'?

Appreciate your feedback!

Lew

So you have a clear shot to the horizon from NE to NW from 2' AGL? No trees, no houses, no outhouses, no passing Bambis, no leaping walleye, just a flat plain? Nothing that could cast a shadow on the sensor at any time of day or year?

[FarmingtonWeather]

I think you'll find the rain gauge bracket will be unstable and you will probably suffer from false rain readings due to the gauge being buffeted by strong winds. I also think you're unlikely to be able to raise/lower the entire unit carefully enough to avoid false rain readings when you want to mow under the structure.

You also think it will be unstable..hmm....I am pretty positive the mast and PVC pipe will be fairly stable, certainly as much as other mast setups I have seen.  The closer to the ground, the more stable it is.  even 5-10 degrees of reflection at the top of the mast will only be a fraction of a degee 2' up if at all.  I can also extend a "leg" down from the bucket to the ground making it more stable if I think that will be an issue.

Another idea is to have a mast in a mast...the bottom part of the main mast could be normal galvanized pipe like I have under my current UV and rain bucket.  Guaranteed not to bend.  The regular mast can extend up through that center pipe and it will flex a little.  

Do you think sliding it up the pole will actually tip the bucket?  It should slide up and down smoothly...a smooth surface against a smooth surface.  I can certainly test that and if that is the case, I can easily delete the false rain reading.  I probably have only mowed 2-3X this whole year due to drought conditions.  

I really appreciate all the feedback and cautions.