Best location for weather sensors

[malc-c]

Hi,

I would welcome suggestions as to the ideal location for my WH1081 sensors. Currently they are fixed to a 40mm x 30mm length of timber bolted to a wall about 8 feet off the ground (the red X marks the spot in the image below)



Now I know that this may not be the ideal spot because the house will shield westerly winds to a degree, but if I describe the garden to you it gave me little choice.

The house backs on to some allotments, with the hedge some 15 feet tall between the top two sheds. Down the left a 6' high fence, with a 6' high conifer tree mid way, closely followed a large bamboo also 8' - 10' high. The lower patio has two conifers around 8' tall, and then on the other side of the RH fence next door has some large apple trees.

I originally though of mounting the pole on the shed near the house, however due to the allotment access between the houses, the wind is funneled up the gap and IMO would give incorrect readings as they would always be from the NW and higher than normal speeds. Also with the bamboo and conifer in the way, all winds from the E and SE would be blocked to a degree.

The next location I though of was along the fence on the LH side, however as it's used for public access I didn't want to risk damage or theft of the sensors. This led to the top sheds, but they are shielded by the high dense hedge and thus would affect the readings to a degree. I also didn't have a decent means of fixing to the wood to keep the pole vertical.

This then brought me to the current location. Having a brick wall made for a secure fixing, and means they are safe from any potential damage from kids etc. However I'm aware that the house is sheltering the sensors to a degree. I guess the ideal location would be on a 20' high pole in the middle of the lawn, but the wife won't agree with that....

Comments please

[sjukmidlands]

What about on the end of the apex of the house roof somewhere? Mine is bolted to the DAB aerial I have there well above the roof, my sister and brother-in-law who had a weather station off me for Christmas bolted theirs onto a redundant satellite dish pole on the side of their house extension, well above roof level.

This would be the ideal location in your circumstances I would have thought, although not allowing easy accesy the the station if you need to change batteries, for instance!

Steve

[malc-c]

thanks for the suggestion... our sky dish is fixed in that location, so that may be an option, although it would make maintenance awkward especially as we don't have a long ladder !

[dane]

How about leaving the transmitter and the rain sensor where they are - or maybe a bit lower for easier maintenance, and move the wind sensors as suggested? meaning you'd need an extension cable, but that's cheap.

[malc-c]

Well I've compromised a bit... and moved it to the top shed.



I'll get the council to cut the hedge (trees ?) down at the back so that it will be below the height of the sensors at some point in the future (they normally do this in March), but at least the sensors won't be protected so much now, and I should get truer readings now, more so once the hedge is trimmed

[daj]

Malcom

Having your rain gauge at the top of such a thin pole is not a good idea. As soon as you get a a gust of wind it will shake the pole causing the rain gauge tipper to move and record false rain. The mechanism is very sensitive.

The cable should be sufficiently long to place your rain collector on top of the shed roof and screw it down firmly. Try to put it a little way from the pole itself if you can

[malc-c]

David, thanks for the suggestion. I'll make the change tomorrow (just thawing out with a cuppa now)

I didn't realise that the sensors were that sensitive... I'll probably have to edit the log files now that I've shaken it up a bit whilst fixing the pole, which I must admit is quite sturdy.

[dane]

Before you move the rain sensor: unplug it from the transmission unit - then you won't get those false readings

[daj]

Good point LB

I keep forgetting to mention that one!

Yes, Malcolm, the rain sensor is amazing sensitive as it is a tiny little tipper (see-saw) which measures 0.3mm of rain each tip, so a tiny shake from you and it will look like you have had a flood

[malc-c]

Guys, Thanks again for the tips.

Can anyone advise how to clear the rainfall settings. I've edited the dayfile.txt file as per the wiki and changed all rainfall to zero for each entry and still Cumulus shows the reading before (have restarted the application and made changed with the application closed.) Is it worth pulling the batteries on the unit or would that loose all my data over the past few days ?

[daj]

Where is is still showing within Cumulus -- today, yesterday, month, etc.

Did you modify the today.ini too? This one is a bit more tricky as you can not simply zero it, but more on that if we need to change it -- depends where it is still showing first

(all of this editing done with Cumulus shut down! )

[dane]

Did you reset the rain counter in the unit?
See the manual for instructions - or see this thread: https://cumulus.hosiene.co.uk/viewtopic.p ... 5&start=10

[malc-c]

Where is is still showing within Cumulus -- today, yesterday, month, etc.

Did you modify the today.ini too? This one is a bit more tricky as you can not simply zero it, but more on that if we need to change it -- depends where it is still showing first

(all of this editing done with Cumulus shut down! )

The rainfall totals are with in Cumulus, on my banner and website data. My dayfile.txt is shown below

Code: Select all

04/01/10,19.0,45,23:18,-3.6,20:10,22.7,18:37,0.0,00:00,1013.5,18:59,0,20:16,0.9,15.4,0.4
05/01/10,0.0,0,00:25,16.3,12:55,21.2,21:25,997.7,23:25,1010.3,00:25,0.0,07:25,0.3,18.8,0.0
06/01/10,9.8,225,15:42,-6.0,23:55,20.2,00:25,997.3,02:55,1007.0,23:12,0,14:55,5.4,10.6,8.0
07/01/10,13.6,45,17:39,-6.5,05:55,0.2,15:25,1006.8,00:25,1016.1,23:57,0.0,00:25,0.0,-2.9,32.0
07/01/10,13.6,45,17:39,-6.5,05:55,0.2,15:25,1006.8,00:25,1015.7,23:25,0.0,00:25,0.0,-2.9,32.0
07/01/10,0.0,0,00:04,00.0,00:04,1000.0,00:04,0.0,00:04,0.0,00:04,0.0,00:04,0.0,0.0,0.0
08/01/10,11.4,45,23:39,-4.5,02:57,-0.1,12:00,1003.1,07:10,1023.4,19:21,0.0,00:02,0.0,-2.5,18.3

The today.ini looks like

Code: Select all

[General]
Date=09/01/2010
Timestamp=09/01/2010 16:30:00
[Wind]
Speed=8.27666473388672
SpTime=16:03
Gust=13.6453113555908
Time=16:03
Bearing=45
Direction=NE
Windrun=27.4397277832031
[Temp]
Low=-4.80000019073486
LTime=03:25
High=-0.300000011920929
HTime=14:40
Total=-2809.99877929688
Samples=1014
[Pressure]
Low=1020.60003662109
LTime=16:15
High=1023.5
HTime=08:55
[Rain]
High=46.776927947998
HTime=14:20
Start=7.19999980926514
Yesterday=0

And yes I did the editing with the application closed.

Did you reset the rain counter in the unit?
See the manual for instructions - or see this thread: https://cumulus.hosiene.co.uk/viewtopic.p ... 5&start=10

Nope... I didn't touch the collector. will check out the link in your post as I'll need this when I've moved the sensor tomorrow

[malc-c]

Well I tried resetting the base unit and still couldn't clear the settings, so I pulled one of the batteries and then stuck it back in after a couple of mins and went through the process of resetting date and time etc.... but still no change

[daj]

Your today.ini still has rain info....

Code: Select all

[Rain]
High=46.776927947998
HTime=14:20
Start=7.19999980926514
Yesterday=0

Close down Cumulus
Take a backup of today.ini

Change High to 0.0
Change HTime to 00:00
Start -- take the amount of rain shown in 'today' in cumulus and add it to the Start value. I think you have 4.2mm today so add 4.2 to 7.19999980926514. So start=11.39999980926514

Having said all that I am confused as you have had 10.8mm rains this month so I would have expected Start to have been at least that figure. Hold off until Steve has a look at this post. thanks