Through every nook and every cranny
The wind blew in on poor old Granny
The wind blew in on poor old Granny
Spike Milligan
After some internet searches it was clear that this was quite a common problem, with most fingers being pointed at the anemometer cups coming loose from the metal shank on which they're mounted. The cups spin round but the shank, which is attached to a magnet that activates a reed switch, remains stationery. As I saw a measurement every now and then I assumed this would be the cause. It was that or the failure of the reed switch. I would need to retrieve the Davis Integrated Sensor Suite, or ISS, and have poke about in its innards.
Inside the ISS
In an earlier blog post Weather Station on a Stick described how I mounted the ISS on the end of an aerial pole that was itself attached to the side of a shed. To save myself a trip up a ladder to remove the ISS, I loosened the pole from the mounting bracket on the shed and carried the whole lot, like a head on a pike, to a table for dis-assembly. Whilst I had the ISS down I thought it would be a good opportunity to clean it, so I fetched some warm water with detergent in it and a cloth.
Before I went any further I checked whether the anemometer was slipping on the metal shaft: it was firmly attached. Bugger - that meant it was likely to be a problem with the reed switch.
ISS Ready for Surgery |
The next step was to unscrew the rainfall measuring spoon (Davis's term) which is the triangular unit between the wind vane and the mounting bracket in the photo above.
Level spoonful of brown stuff |
I then undid the four screws that held the top and bottom of the ISS together. When pulled apart they revealed, well, not a great deal.
Nothing much to see here, move along |
You can't mess with me |
Anemometer magnet - Spinning but no-one's receiving |
No change. There was still no wind speed reading and it still only recorded a gust two or three time a day; professional help would be required. I knew the Vantage View was way out of warranty so I looked at the support pages of Prodata, the company I had purchased it from, to find out what my options were. In short, limited. Davis servicing and repairs for the UK are dealt with by McMurdo Ltd in Portsmouth who I would need to phone or email prior to returning the whole ISS unit.
During the period the ISS was away for repair there would be no weather recording - not that this would be a huge blow to UK meteorology - but I'd miss it. So, I demurred, hoping to find an alternative way to rectify the problem.
Time is the Great Healer
It's now working. The wind speed is constantly updated and gusts are recorded correctly. How did I achieve this? By doing nothing - it just started working again, about a month after I'd dismantled it. I still don't know what was wrong with it or how long it will continue to work; time will tell.