Cumulus Support

Hi,

I'm looking at extending the wind sensors and would welcome some advice.

The station is already mounted on a sturdy wooden pole attached to our garden shed



However as you will notice it has trees to the east and this must obviously cause incorrect readings. I'm looking at keeping the stock cables, so I'm limited to the height I can go, but I'm thinking that a 2m tube should give enough clearance of the trees / hedge.

B&Q are selling 22mm chromed copper pipe for £20 a length.. would this be suitable or can anyone recommend a suitable alternative

Hi Malc.

you need to be very carefull extending poles, especially when in a windy area like here in NW.

Every extra metre of height will probably double the wind loading, putting stress on the pole and its fittings.

Copper will be totally unsuitable as its far too soft. Ally, steel or glass fibre are better.

You will also need to look at access. If a fault occurs in mid winter do u really want to drop poles or climb on ladders or roofs to access the kit?

My set-up is exactly as yours is now and its been up since June 2008. I have a 1 m steel pole attached to a wooden shed wall with ally fittings. Its bolted right thru the wood and has large washers on both sides to spread the load. Its all coated in 'denso tape' for waterproofing.

Hope this helps

I agree with Phil, the copper pipe would be too soft.

I used 1" galvanised water pipe. (You can see it as my background image here http://members.optusnet.com.au/ktau/wws/index.htm)
The mast is 5 to 6 metres high and the cable extended into the Stevenson Screen.
Had a near 60 KM/h wind gust on Jan 22nd and it didn't blow over

If you know a plumber he might have a piece lying around that may suit your needs.

These two threads may interest you.

https://cumulus.hosiene.co.uk/viewtopic.php?f=16&t=2246

https://cumulus.hosiene.co.uk/viewtopic.php?f=16&t=2304

Hi
With those trees around you certainly need to do something - when they are in leaf the wind sensors will get all sorts of problems.
I am lucky enough to have a tall barn but even then I needed to use a 2.25 metre pole to get above the trees. 32mm aluminium with bracing wires in four directions. Even then the pole bent slightly in a gale.
Search the forum for info about the rain sensor mounting (not good on a pole) and improvements to the transmitter screen (not well protected with the little thing provided plus temperature errors etc). The wind sensor cable can be extended quite a bit if you can find a better site away from trees.
Regards
Alan

Guys, thanks for the replies,

At the moment the set up is very stable, having used large bolt screws and washers. Given the agro it could be to perform maintenance on the equipment I'll leave it as is. Might be a better investment to have the hedge / trees pruned so that they are a couple of feet lower than the mast.

Alan, yes I did see the image of your set up on one of those threads - looks nice. I'm looking at re-locating the rain sensor lower and on a stable section of the shed, which was why I started a post on cable length. At the moment the wind can blow through the branches, but as you said, come summer it will be like a brick wall.

Well, not the cheapest option I know... but I've booked a chap to cut the tree's down to the height of the shed, so my gauges will be in the best location I can get, other than fitting it to a pole attached to the chimney on the house - but that would involve hiring a large ladder, a roof ladder and having a head for heights

Well I've received a PM from a member and on reflection of his comments have now contacted the contractors and informed them their service will not be required.

I didn't really want to lop 8 - 10 feet off the hedge as it provides us with lots of privacy and I was so wrapped up in this weather watching / data gathering thing that I didn't see the overall picture.

Looks like I'll either look at re-locating the array or make do with the reading I get given the location we live in.

Hi Malcolm,

I used an aerial pole. The small pole sections provided with the kit are inserted inside the aerial pole top and bottom, held in place with self tapping screws/bolts. This allows me to have the transmitter at the bottom and the wind vane at the top. I got extra length bolts and nuts to secure the water gauge mid way down. I haven’t yet completed everything to my satisfaction but it is quite neat and secure (you will be able to use a straight pole, I won’t go into the reasons why mine is bent!).

Neil

A quick observation (and I am no expert on this), but the sensors for temperature, pressure, etc are very close the the wall of the building -- you could get inflated temperature readings as your wall will radiate heat

It's sited there because it is on a north wall; it acts as a shield from the sun - that's the theory anyway

Neil,

Thanks for the tip. I'll take a look at the various aerial kits, it's certainly given me an idea. I like seeing these sort of installations, and as David commented on the position of your pressure / temperature unit could cause you problems if the wall radiates heat, shows that we all have to make compromises to get the ideal optimum for our given surroundings. I too follow your logic as it would never be in direct sun light, and unless you have no insulation in your walls, it shouldn't pick up radiated heat (in theory)

The north wall of our house is too far from the wind sensor pole to do that here.

Here are before and after photos of my pole extension. The after was before I tidied up the cable.

Gina, thanks for the pictures.

I've been googling aerial masts and found places that offer 10' x 1" diameter and up to 20' in 2" diameter (strange that the cheapest is always too far away and they only do collect in person )

I've got a few ideas, just need to locate the right parts and work out the bracing.

Well I've just ordered an 8 foot mast (1.5" diameter), a handfull of brackets and some V clamps for less than £20 inc delivery, so next weekend I'll be having some fun sorting out the installation

Originally I intended to fix the mast to the shed at three points, but that wouldn't give me anymore height than I already have, so I'm going to replace the 40mm x 30mm wooden post with something a lot more substantial and then secure the 8' mast to that, hopefully raising the wind sensors five or six feet. The temp sensor and rain meter will be lowered and fixed to the wooden post to avoid vibration in high winds, and I might even look at making one of those fancy shields like Gina has to reduce incorrect temperature readings on warm days.

At least this option turned out to be about 1/5th the cost of having the trees cut down !

I found a lot of useful advice on weather station sensor location here: http://myweb.tiscali.co.uk/awsguide/
I've yet to follow most of it.