I want to add a anemometer to my Arduino weather station, and I want to use a 3v motor.
How do I do this?
I have a motor, and I have wind cups, but I don't have code.
If anyone can help, it would be greatly appreciated.
Daniel
What is the purpose of the motor?
Did you get an anemometer kit, or are you building from scratch?
@markd833
I am building from scratch. The motor will act like a sort of generator, the arduino will measure that and display the speed on my tft screen.
Ok. If i recall correctly, most anemometer setups generate pulses from either an optical encoder wheel or a simple reed relay. Your setup then simply counts pulses over a fixed period of time and apply a calibration factor to determine wind speed.
I suppose it would work using a motor as a generator. You might need to experiment to see if there is a linear relationship between rpm and volts out.
You will need to map the output of the motor to the wind speed and make a table. You then need to know the range of values and decide how you will get them within the range that an arduino can be connected to. I would not assume a 3v motor can’t get higher than 3v
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I pulled apart a old anemometer, that's where I got the motor and cups from, so I know it can be done, I just need to figure out HOW to do it
I'll start work on that tomorrow.
Are you sure the device is a motor?
Yes, 100% sure
Your problem is going to be calibration as, if you don’t know the wind speed how do you create a wind speed and anemometer table. I’m sure some rig could be devised but would be easiest to compare with a working anemometer to get accurate results. Unless you have a wind tunnel!
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You'll need hurrican force winds to begin to use a 3v motor.
I would have thought that it would be easier/better to keep the existing hardware/mouldings etc (unless of course it's broken in some way). Otherwise it seems like you're chopping up a boat to make a raft...
Does the original anemometer have any identifying marks on it? Maybe you can trace back to a manufacturer and get some specs.
Come on.
We want photos. 
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I had one of those anemometers until the bearings on the motor wore out. You need add a resistor across the output connections of the motor in order to calibrate it and limit the voltage maximum. Any small, brushed motor will work.
I made an anemometer that used a Hall Effect sensor that generated pulses. This may help to calibrate you motor.
In order to calibrate it I made small board that had a mega328 chip, a GPS (Neo6M) and a battery backed SPI SRAM. The code would count pulses for 1 second and write the pulse count from the anemometer and the ground speed from the GPS to the SRAM. I mounted the anemometer rotor on a mast in the back of my truck. The mast was tall enough to get it into clean air. I would drive one direction at different speeds then turn around and go back the other way to minimize the effect of wind. Then I downloaded the data from the SRAM and made a table in Excel to develop a speed v pulse count curve. Seemed to be pretty accurate when done.
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Yes you do. It's the example sketch "Graph" under "communications" in the IDE examples menu.
Here are the pictures of the original anemometer. The main chip on the main board stopped working and I can't find the main board, but the other parts are still here.
Just found the main board and put it back together so everyone can see how it works. The correct LEDs do not light up so I think something is going wrong with it, which is why I pulled it apart in the first place.
Replace the LM324 and it will likely work again.
@Paul_KD7HB
How do I connect it to my arduino then?