Davis VP2 ISS Siting Advice Please

[Dr_G]

Hello,

Happy Christmas etc.

O.K. I admit I have had my VP2 for several weeks now, and in that ime I have obtained very detailled weather data for for inside my office. Zero wind, and about a constant 20 degrees inside and outside. I think the ISS and anemometer would be better outside (even though I am loathed to get them dirty or wet).

I installed a post in the vegetabe patch this afternoon, but it looks daft. The Iss seems vulnerable too (squirrels, pigeons, escaped criminals etc.), so I am wondering if I can realisticallt mount it at eaves level on the house, facing approx. SW? It will be in a corner which I suppose will be a bit of a sun trap and will give rubbish temo readings in spite of the ventilated shield? Also, the rain gauge will be exposed well enough, but it will be in the 'valley' of three pitched roofs (in plan the roofs form a 'U' shape.

Is the above possibly the worst location ever for an ISS, or can I get away with it? Is there any good place to put the ISS on a house?

By the way the anenometer is going on a ridge tile, an a 1m pole.

Cheers,

Garth.

[pottyprof]

Hello,

Happy Christmas etc.

O.K. I admit I have had my VP2 for several weeks now, and in that ime I have obtained very detailled weather data for for inside my office. Zero wind, and about a constant 20 degrees inside and outside. I think the ISS and anemometer would be better outside (even though I am loathed to get them dirty or wet).

I installed a post in the vegetabe patch this afternoon, but it looks daft. The Iss seems vulnerable too (squirrels, pigeons, escaped criminals etc.), so I am wondering if I can realisticallt mount it at eaves level on the house, facing approx. SW? It will be in a corner which I suppose will be a bit of a sun trap and will give rubbish temo readings in spite of the ventilated shield? Also, the rain gauge will be exposed well enough, but it will be in the 'valley' of three pitched roofs (in plan the roofs form a 'U' shape.

Is the above possibly the worst location ever for an ISS, or can I get away with it? Is there any good place to put the ISS on a house?

By the way the anenometer is going on a ridge tile, an a 1m pole.

Cheers,

Garth.

Ideally north facing at about 2 metres high for the ISS Have you got any natural shading in the garden you could utilise?

[Cloudburst]

Hello,

Happy Christmas etc.

O.K. I admit I have had my VP2 for several weeks now, and in that ime I have obtained very detailled weather data for for inside my office. Zero wind, and about a constant 20 degrees inside and outside. I think the ISS and anemometer would be better outside (even though I am loathed to get them dirty or wet).

I installed a post in the vegetabe patch this afternoon, but it looks daft. The Iss seems vulnerable too (squirrels, pigeons, escaped criminals etc.), so I am wondering if I can realisticallt mount it at eaves level on the house, facing approx. SW? It will be in a corner which I suppose will be a bit of a sun trap and will give rubbish temo readings in spite of the ventilated shield? Also, the rain gauge will be exposed well enough, but it will be in the 'valley' of three pitched roofs (in plan the roofs form a 'U' shape.

Is the above possibly the worst location ever for an ISS, or can I get away with it? Is there any good place to put the ISS on a house?

By the way the anenometer is going on a ridge tile, an a 1m pole.

Cheers,

Garth.

Hi there. You will have to point the ISS south or at least in a southerly direction to charge the solar cell. Remeber that having the ISS near a house will raise night temps during winter as brick materials, slates etc release infrared heat so this will push up your night minima, maybe talking only about a degree or so though. Ideally you should place the ISS 1.2 meters over grass in a well exposed area as in terms of airflow you dont want to put it in a suntrap type setup as there isnt sufficent airflow. If you really have to mount to the house then it would probably be best to fix a mount to the side of the house, such as a 2 meter pole or so to move the ISS away from the house, but to also maximise exposure to the rain gauge (this needs to be at least 10 m in all directions). Its best to mount the rain gauge at or above the level of surroundings as if in the case of a gusty wind and rain, it will simply flow over the top of the bucket due to objects around it being higher.

So the key point really is to place the ISS in the most ventilated and exposed spot you have, and if you have the wireless version you must point it south in order for the internal battery to charge. If this means placing it on the side or very near you house then try to get it raised up aboive the roofline if its a slanted roof.

Edited December 29, 2007 by Cloudburst

[Dr_G]

Hi there. You will have to point the ISS south or at least in a southerly direction to charge the solar cell. Remeber that having the ISS near a house will raise night temps during winter as brick materials, slates etc release infrared heat so this will push up your night minima, maybe talking only about a degree or so though. Ideally you should place the ISS 1.2 meters over grass in a well exposed area as in terms of airflow you dont want to put it in a suntrap type setup as there isnt sufficent airflow. If you really have to mount to the house then it would probably be best to fix a mount to the side of the house, such as a 2 meter pole or so to move the ISS away from the house, but to also maximise exposure to the rain gauge (this needs to be at least 10 m in all directions). Its best to mount the rain gauge at or above the level of surroundings as if in the case of a gusty wind and rain, it will simply flow over the top of the bucket due to objects around it being higher.

So the key point really is to place the ISS in the most ventilated and exposed spot you have, and if you have the wireless version you must point it south in order for the internal battery to charge. If this means placing it on the side or very near you house then try to get it raised up aboive the roofline if its a slanted roof.

Guys,

Thanks for the comments. My system is cabled by the way, so I am trying to minimise cable runs, hence fitting to the house is by far the easiest option.

If you have say a 45 degree roof slope either side, and to the back of the rain gauge (gauge fitted as I said at eaves level, top of collector protruding above gutter line), doesnt this effectively mean that rain would have to be blown at more than a 45 degree angle before it had any real effect on the amount of rain collected? Anything less than 45 degrees would not be affected by the three apexes of the roof (neglegting any updraughts).

Having my ISS 10m from any obstructions isn't going to happen, whether it is in the garden or not! We have a lot of trees.

Cheers,

Garth.