Placing My Weather Station

squonk

I've enclosed pictures of my garden. I was thinking of putting the weather station sensors (getting a VP2 at the weekend) on a pole on top of the shed. Anyone got any thoughts about whether I should do something different? I have a block of apartments behind the garden due NW.

It's going to be far from ideal unfortunately as you are very boxed in by the looks of things,with houses all around you.
Thats going to affect your sunlight hours which will have an affect on your temperature.
You are also going to get a heat island effect bigtime there.

What that means is,your system might be reading too warm in winter for snow and low and behold it does snow (It won't snow anyway but how and ever ) because it's actually in ambient terms a degree or two colder than you are registering.
Ditto in the summer,you will be getting warmer readings than what a met office would liken to being the actual.

If I were you I'd construct some kind of support structure in the centre of that garden to at least have the temperature unit and rain guage above the fence level.
I'd get some extra cable and mount the anemometer on your chimney.It's likely to get good readings up there and is accessable for maintainence-which you shouldnt have to do too often.

Paddy.1

Hi Squonk. I think it would be a bad idea to put temperature sensor above roof on a pole as radiation and height will effect true readings. The temp sensor needs to be place to be about 4.5 feet over grass to get an anyway true reading, above or below this would read cooler or higher.

Your garden is something like mine, so I got a small stevonson screen:
http://www.ukweathershop.co.uk/acatalog/installation_kit.html
(under "simple Screen". and it does the job perfectly. Sheilds sensor from radiation from buildings, sunshine etc. Just hang this screen on a wall or fence away from the house, over grass at 4.5 feet height an bobs your uncle. With the wind sensor, the roof is defo the best job.

squonk

Thanks Paddy! he he! Obviously this is going to be an ongoing project with a bit of an experimental period!

Paddy.1

no problem. I meant to add that if you do get this Screen, it is a good idea to have it out from the wall or fence by about a foot. A couple of lats should do the job. (this just allows more movement of air within the screen). I am lucky enough to have a large open space at the back of my house. But you should get near perfect readings as well, it is just a matter of time and effort. (precious at any time:))

Mothman

Firstly decide whether you want to record the conditions in your garden or the ambient air.

If the latter like most of us, then you may forget about the 4ft standard and as BB says get the unit above the fencing and into the air flow above fence line. Certainly in the middle of grassy area is best, but probably not practical if you use the space otherwise.
If this is the case, then IMO the shed probably is best option.

Most of the above refers to temperature, but the Davis unit is somewhat compromised by having the temp and rain sensors together. So for rain, the unit should be as far away from houses, again making the shed (furthest from houses) most suitable as a mounting structure, and pole above the shed is probably best compromise but as near over grass area as possible.

The anemometer is best at top of house, but you have to decide how much that effort is worth to you, and you may assume it'll need regular servicing, ie once/twice a year. Spiders/earwigs regularly foul mine up. You may be fortunate and not have any issues for years, but from personal experience, I wouldn't count on it.

Snowbie

Also the cable length iirc is 40 feet from anemometer to the intergrated sensor suite on the main station itself.Usually enough for the most part but just bare in mind if placing up on chimney and you have the perfect spot for your station with no length of cable left.

There is a Davis wireless transmitter for this purpose,though at added expense.

Mothman

Snowbie wrote: »

Also the cable length iirc is 40 feet from anemometer to the intergrated sensor suite on the main station itself.Usually enough for the most part but just bare in mind if placing up on chimney and you have the perfect spot for your station with no length of cable left.

There is little issue with adding a cable extension. The cable is similar if not the same as telephone cable and electrical store, should have it and external connectors.

Snowbie

I think MM after 40 feet the response time between anemometer and the ISS would decrease if using a coupler or extended cable.You could lose vital wind speed and accuracy 10 min avg plots. It be the same if your DSL line for router in turn for broadband is on an extension cable away from the main line in access point(socket) in the house.

Mothman

Snowbie wrote: »

I think MM after 40 feet the response time between anemometer and the ISS would decrease if using a coupler or extended cable.You could lose vital wind speed and accuracy 10 min avg plots. It be the same if your DSL line for router in turn for broadband is on an extension cable away from the main line in access point(socket) in the house.

You're making me work hard

The specification sheet does not mention losing vital wind speed and accuracy 10 min avg plots. It mentions a decrease in maximum windspeed and that "The accuracy of the reading below the maximum is not affected."

My interpretation is that one could add 50m without impacting on windspeeds recorded here. ie 100mph+

Snowbie

Mothman wrote: »

You're making me work hard:)

Have to keep you on your toes, I dont want you to freeze to death down there:)

The specification sheet does not mention losing vital wind speed and accuracy 10 min avg plots. It mentions a decrease in maximum windspeed and that "The accuracy of the reading below the maximum is not affected."

My interpretation is that one could add 50m without impacting on windspeeds recorded here. ie 100mph+

Ah good find,i didnt know that,i should read manuals from now on so.You would think now the wireless anemometer kit be obsolete within those specs for length of cables.

Mothman

Snowbie wrote: »

Have to keep you on your toes, I dont want you to freeze to death down there:)

Still above freezing here..........just

Snowbie wrote: »

Ah good find,i didnt know that,i should read manuals from now on so.You would think now the wireless anemometer kit be obsolete within those specs for length of cables.

Yes, but sticking up a transmitter is so much easier than long lengths of cable, though I found with the VP1, that the more transmitters operating, the worse the reception.
I wonder if this situation improved with VP2

Snowbie

I have 3 wireless transmitters currently MM with my VP2,obviously the Iss,soil temp/moisture station and seperate hum/temp and the reception is spot on.

I did have the anemometer transmitter kit with the VP1 and had it placed on the chimney but found the higher the anemometer the more interference and kept dropping the signal when lower it was fine even if it was place at ground level at same distance from Iss,probably was too much interference at that height? then after i took it down i found out you could get a repeater for it to improve signal:rolleyes:

So i reckon the VP2 signal has improved vastly over the original VP with a 1000' range from console to Iss to begin with and also using a stronger frequency for all transmitters.Mine are running with it for over a year now without hassle.

squonk

Thanks lads! All this advice is great. The latest is that the delivery has been delayed til Monday due to bad weather somewhere I'd hoped to spend Saturday getting it up and running at least.

Not sure what I'm going to do about the anemometer. I really don't want to put it on the chimney. I don't fancy scaling the roof once or twice a year for maintenance. I might try and get it mounted high up somewhere at the back of the garden.

I like Paddy's Stephenson Screen idea. That could work for my temperature readings. I think it'll take me a few weeks to get an idea of what works best for me. Ah, the fun of the learning process!

Mothman

squonk wrote: »

I like Paddy's Stephenson Screen idea. That could work for my temperature readings. I think it'll take me a few weeks to get an idea of what works best for me. Ah, the fun of the learning process!

The VP has its own radiation screen and it works very well.

squonk

squonk wrote: »

I like Paddy's Stephenson Screen idea. That could work for my temperature readings. I think it'll take me a few weeks to get an idea of what works best for me. Ah, the fun of the learning process!

You won't need it.
As Mothman said,the VP has it's own.
I've had a VP2 for a couple of years now.
Again,it's a choice as to whether you want to measure the ambient temperature or the actual temperature in the garden.
The former is way better and more realistic vis a vis what other more exposed stations will be reporting and will mean your reports will look more sensible.
The main reason for instance that Met Éireann used to advance the downgrading of their Clones and Kilkenny stations was they felt that their readings were being compromised by the proximity of local housing.
They would probably be talking about exacting standards though.

My VP2 is mounted on a timber square stake available cheaply at any hardware store.It's an 8 footer with about 2ft dug in the ground and 6 ft over the ground which should get you above fence height.

squonk

It arrived just before lunch. Unboxed it just at the moment. Have to look at the manual next!