looking for an anemometer

Re: looking for an anemometer

What you want is a 4-20 ma, not 0-20. The 1-5 volts comes from the 4-20 ma output across a 250 ohm resistor, which an A/D converter reads and converts to digital. In some cases you can fake the 1-5 volts by using a different value resistor, it all depends on if it has it's own output or is loop powered. But if all you are doing is tweaking turbines, it would have to be at the same height as the turbines, or very close to it. None that I ever saw directly put out the 4-20, all have to be converted somehow. For a heater you are talking a whole different ball game, as the wire size would have to be much larger to handle the current for the heater. With most PLC's you can get different modules to read almost anything reasonable, up to around 250 volts input. Or just go with a cheapy, like this http://www.amazon.com/Inspeed-Vortex-PM25-Mount-Anemometer/dp/B0034ULB74/ref=lp_13825011_1_6?ie=UTF8&qid=1380485590&sr=1-6