I'm working with a fan that creates vacuum and I want to control its speed effectively. I monitor the vacuum level with a manometer, aiming for a range of -0.3 to -0.6 inches of water column, but at full power, the fan pulls -0.8 inches WC, which is great! The problem is that I've tried using three variable speed controllers, but they all shut off after a few minutes, leading me to believe that the thermal protection in the controller might be causing this. After waiting a bit, the fan restarts fine but then shuts off again shortly after. It seems to be running at around 50-60% power. I'd love to know what type of controller would work best for this fan motor, which is from Vevor with specifications of AC120V 60Hz, a power rating of 585W, an air volume of 3198CFM, and a speed of 3370rpm. Thanks!
2 Answers
You might want to try a triac-based speed controller instead of those variable ones you're using. It sounds like your motor’s heat protection is kicking in, which happens a lot with cheaper controllers. Triac controllers are better suited for AC motors like yours since they can handle higher loads and better manage the thermal aspects of the motor. Just make sure the one you choose can handle the wattage!
It sounds like your fan might be drawing more current than the controllers can handle. Check if your fan is rated for a continuous load; if it isn't, you might just need a more powerful controller that's designed for industrial use. Look for something that specifies it can manage higher wattage and continuous operation—should resolve the shut-off issue!
Definitely worth checking the load ratings! My previous fan setup had similar problems until I swapped to a robust controller.
Yeah, I had a similar issue, and switching to a triac controller really fixed my shutdown problem. Just be careful with the ratings!