Topic: How much movement matters?

[pjon]

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On the left is my old Fine Offset weather station. In the background is my new Ecowitt weather station. Not visible here are

1. House from which photo was taken (with zoom on camera)
2. Trees on left and right

The old weather station is in a less than ideal location as it's not well above the house and it tends to show the wind coming from only one direction (which is mostly true because of local topography, but not always). It's still in operation, uploading data via WeeWX to my site and to some online services. I plan to cut over all that to the new station in due course.

I don't have a perfect location for the sensors and with the old station I traded off ease of replacing batteries and cleaning rain gauge, plus convenience of using existing vegetable patch pole, against trying for something that might better show a bit more variety in wind direction.

The new station has rechargeable batteries and a solar cell, so should not need as much maintenance, and I have positioned it higher up (the property is on a slope) where it's clear of the house. It's about 3m clear of the ground. As can be seen there's one tree close to it, but in a direction the wind pretty much never comes from. The other trees, further away, are deciduous -- much less dense -- and less likely to affect wind direction readings. Already I see much greater variability in wind direction.

To facilitate maintenance I put the new station on a pole that is sunk into a 6 inch deep block of wood, 3 inches square, in a metal fence post spike. If I loosen a couple of bolts I can slide the 8ft pole out. Yesterday, during gusts of up to 40km/hr, it was shaking a bit at the top. I think the pole is too long and insufficiently rigid in this setup so I'm going to have to redo this.

At the moment I can't see the level indicator on top of the unit -- I need a step ladder (or a periscope ).

Meanwhile, I'm wondering

1. How much does vibration really matter?
2. Ditto having the instruments precisely level?

I assume that both matter most for accurate rain gauge readings but am curious just how critical these are.

[Notsorusty]

Not being a total expert but the shaking of the pole by the wind will probably make the tipping spoon register false rainfall.

Without getting an aerial crane or sky hook I never really understood how you could utilize the level at the top of the unit. My best suggestion is to make sure the pole is "perfectly" straight up and down by using a level on the pole.

Others may have better solutions.

I like the garden, can you post a photo when spring starts everything blooming?

[Rover1822]

Yeah, I find the top mounted levels useless, how many of us mount the station in a position where we can see on top of it. I'm sure there are some though.

[galfert]

The all-in-one type stations should not be mounted higher than 14 or 16 feet. If you get an all-in-one designed station then your optimal mounting is also a compromise between the ideal height for temperature/humidity, rain and wind.

That said the mounted level is for the rain gauge. You'll notice that anemometers that are for separate type stations don't include a level. Therefore the level is probably not out of reach if you stick to the recommended height for the all-in-one design.

Of course it is your station and you can do what you want with it. But that is my take on it for what it is worth.

[pjon]

Thanks all.

The pole is 8 ft, so not too high AFAIK, but seeing the level on top is awkward just now (ground is soft, sloping). I'll rope other half in to help on a dry, calm day (ie hold the step ladder). I gave up on the metal fence spike and used some metal hose clips to tie the pole to a very sturdy wooden pole about 4ft high. The clips at their tightest are not quite tight enough so I will have to get some more /sigh -- but it's an improvement.

Some garden pics here: https://imgur.com/a/lZ8JCjC.

[Rover1822]

Really nice garden!

I would note that your weather station height , should be higher , for wind measurements , as it is currently, you are getting really turbulent air , but eh.

I don't rely on the "bubble" , when I mount I make sure the substructure mount, be it a pole, whatever is squared off and level... then its just making sure where you attach is also flat and follows what you have done.

[Platokidd]

From what I found with both my pws- No matter how level the pole is the array bubble level will be off.  Honestly I don't think the 2902 array is level to itself.

They only way I found to make the array deadnuts level was to use 2 of these. Then you can adjust by offsetting.
https://www.amazon.com/gp/product/B003EAY89M/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1