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Making an Anemometer for the Windmill
After getting the windmill up, I was getting tired of just guessing on how strong the wind was. I had an old Radio Shack AccuWeather Station that I had laying in my parts pile for a few years now, it is just the staion itself, I did not have any of the actual sensors, never had a use for it until now! So I did some research (again, on the web, there is a vast amount of info on just about anything on the web!) on how the anemometer was interfaced to the unit, simple enough, a magnetic reed switch was located in the base and a magnet was located in the cup assembly, I did not have the cups, but I did have the base of the anemometer, so I took some measurements off of it to see where all the components were located in relation to each other and this is what I did to make it work.....

(June 26, 2009)
This is the weather station main console, apparently, all sensors connected to the unit via an RJ45 type connector, so I could build my interface board and add an ethernet connector to it and I will be able to connect that to the unit without modifications to the actual station.

Eventually I will rebuild the rest of the sensors for it such as the wind vane, rain gauge, etc... for now we just need the anemometer.

I took a small perfboard to solder all the connectors to for the interface, this will serve as the "Sensor Box1" for the unit. I had salvaged an ethernet connector off of an old ethernet card to use.

(I don't know if many people notice, but most components I use when building one of my projects are usually salvaged from somewhere else. This makes it to where I don't have to have a large budget for my hobby, the only downside is, I usually have to put some of my projects on hold until I can find somewhere or something to salvage a needed part from!!)
(Click on image to be taken directly to website containing these schematics)
Click on image to be directed to site containing these schematics
This is how the anemometer and the wind vane connected to the system, simple enough, and I believe I have all components on hand including a small magnetic reed switch I had salvaged out of an old controller module for a Gazelle exercise machine.
I had a small circuit board I salvaged out of a printer paper detector circuit, I stripped all the components off of it and soldered all the components on to it for the reed switch assembly.

I cut a small section off of a bic pen to use as the housing for the sensor. Once the sensor was placed inside the tube, I used some hot glue to seal both ends of the tube to make it water proof.
I used an old 4 head VCR pickup drum for the main rotating assembly, since this already had bearings, and it is made out of aluminum it wont cause any problems with the magnet. I removed all the electronic components on the head unit, and I turned the drums on the lathe to remove the sides off of them and ended up with 2 flat plates, one with the bearing assembly and one with the shaft. I then drilled a hole the size of the bic pen tube at the same location it would have been located in the original assembly, and hot glued it into place. I mounted that onto a 3/4" CPVC "T" connector and attached that to a short length of 3/4" CPVC pipe. I ran the wire of the sensor inside the "T" and attached an RJ11 type connector on the other end of the "T", that way I can just run a long phone cord out to the sensor once it is mounted onto the windmill pole.
This is the RJ11 (phone jack) connector attached to one side of the CPVC "T" connector. I took a phone cord coupler and separated its housing, cut the wires in half, and whala! I have 2 modular RJ11 connectors with solderable leads.) It is sealed with hot glue also to keep moisture from getting into the connector housing.
I then glued a magnet onto the cup mounting plate, and secured it in place with some more hot glue. I then took three of the large "egg" shaped clear domes you get from "gumball machines", and glued them around the circumference of the cup plate.
Here is a shot with the whole assembly put together. The other end of the CPVC pipe it is mounted on will support the wind vane once I get that done, right now it has the wind vane attached and mounted but no electronics to interface with the station, I have to find a potentiometer suitable for the job before I can finish the interface for it.
Now it is just a matter of plugging in my interface PCB to the main station......
Now I can actually monitor the "real" wind speeds, I don't know exactly how accurate this station is but it gives me a good referrence point for now, I was thinking of mounting it on the truck on a windless day and matching its output with the GPS or speedometer just to see how accurate it was, just have not gotten around to doing so yet. Eventually once I get all the sensors done I will interface it to the PC so I can log some of the data.
Here it is mounted off the windmill pole...... here you can also see the wind vane, it doesnt register anything on the console yet, but it serves as a good visual indicator on which way the wind is blowing....

Next project for the weather station entails making the rest of the sensors for it and having the data logged onto a computer and possibly have it displayed on a page here on my site in real time, I was also thinking on adding a web cam right on the yaw pivot post, so people can see whatever direction the windmill is facing, but that's another project on its own.....





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