Polarity of fan motor? Answered
Recently I had occasion to change the small fan that cool the aluminum fins just above the exturder. Not paying too much attention to the polarity of the 12 volt supply voltage, I figured that if was turning the wrong way, I could easily change the plus and minus connection. When I fired up the controller, I thought it was turning the wrong way and I changed the polarity. It then wouldn't turn at all. Changing it back to the original polarity, it worked fine. It is normal to have the fan polarized, and if so, what is the proper direction of air flow?