I have the dreaded problem of recording a lot of rain when winds get above a threshold speed (around 25-30kmh) most likely due to vibrations in the mounting pole. I am using an aluminium pipe sleeved over a steel tv antenna mast, both mounted on a wooden fence post concreted into the ground. total height 5m. I have steel triangular bracing rods attempting to hold the thing still, but I still get some sway in strong wind gusts, and thats obviously enough to trigger the rain sensor.
After a lot of work trying to get this stable and vibration-free, I have finally come to the conclusion that its never going to happen. So, one solution is to get a second Sky unit to mount near ground level on a vibration proof rubber mount just to measure rainfall with.
Two questions - is it possible to purchase additional Sky units? If so, will a second one work with my base station, or is it just one Sky per base station?
yes, it is possible to connect two Sky units to the same hub. But if you really care about accurate results, you are better of with a more traditional tipping bucket device. The disadvantage is that you don’t get an alarm from it with the first few drops, and that it doesn’t integrate in the native weatherflow system. If you are using one of the available third party interfaces, you might be able to integrate it.
I don’t know if they are selling only a Sky unit, but you could ask them directly.
Sway doesn’t necessarily cause rain as can be seen in the video I linked in this post: Photos of Air and Installation. It is possible you are getting vibrations from the fence, unless it is just a stand alone fence post. When I had the pole shown in the video attached to my chain link fence it picked up false rain but mounted rigidly to my RV as shown, it doesn’t get false rain except when the RV gets shook.
I purchased extra Skys a few months ago so you should be able to.
I have several Skys running on a single hub.
I have a sky on the tall pole that records false rain when over 25 knots wind.
That tall pole has a wind sock flapping around and guy wires yet I was able to build a mount that stopped the false rain.
In my opinion the expense of purchasing a second Sky purely to measure rainfall might be better spent on removing any vibration through your pole.