The vortex wind sensor does not have any voltage it uses a simple reed switch. This device connects to the surge protection dedicated for the vortex on the circuit board.
This device is connected to a voltage snapback circuit, there is a LED which eliminates to indicate the 5 v line is working correctly, this voltage line has a fuse connected to protect from cable shorts .
E-vain uses a 5 V supply coming from windworks interface this goes to a Hall effect sensor, and varies the voltage output by using a magnetic field .
There is a double snapback circuit, one for the 5 V supply and one for the output voltage supply and ground.