I have a Vortex and e-Vane connected to one of the new Hobby Boards Anemometer Control Boards (ACB). I’m reading the values using OWFS and custom software on an ALIX1D with a view to feeding the data to Meteohub and from there to WD. The combination is working great, except when it rains!
I am querying this on the Hobby Boards Forum and by mail with Inspeed but wondered if anyone here had any ideas, so here’s the detail:
Since installation on the mast (10m fibre glass) it has rained on the 3 occasions. Only around 0.5mm (0.02") per hour for around an hour each time, so pretty light rain, but on each occasion the Vortex/ACB combination has suddenly started reporting around 10 times the number of counts that actual rotations would account for (I can see the anemometer, and there is an Oregon Scientific WMR928 anemometer mounted lower down the same
mast), e.g. over 100mph in place of 10-15 mph. A while after the rain stops, normal reporting of wind speeds resumes.
So far as I’m aware all connections are waterproof. The Vortex end is as supplied. The standard 25’ wire is joined to an extension which is ~10’ of 6 core (2 cores for the Vortex, 3 for the e-Vane, 1 unused) alarm cable inside a small IP55 box with all wires entering from the bottom and the joint itself sealed with liquid electrical tape. The extension joins to the ACB inside an IP65 box close to the base of the mast, again the cable enters from the bottom, in this case the connectors are coated in dielectric grease. In both IP boxes the eVane connections are on the same cable and connector blocks as the Vortex ones, and the eVane has behaved fine throughout.
There are no obvious sources of RF in the area (assuming that the WMR928 anemometer Tx isn’t powerful enough to be significant), and it only happens when it rains (so far).
Does anyone have any ideas about cause or cure?
A few random thoughts I’ve had include…
Could the ‘wet pole’ be acting as an antenna and picking up RF which then gets passed on to the wire? If so maybe it would help if I replaced most of the wire from the head to the ACB with twisted pair (I have some UTP patch, ans some FTP solid)?
I know the “serial plug” Vortex has a small capacitor between the wires at the plug end. I’m not an electronics guy so I’m not sure of the logic behind that. Maybe some sort of smoothing or amplification? Might adding one have some role here?