GE Z-Wave Wireless Smart Fan Speed Control, 3-Speed, In-Wall

[JDRoberts]

@CAL7

I take it as gospel not to connect a light dimmer to a motor, but I don’t know why. Slowing a motor must use completely different technology than dimming a light?

Yes, exactly. Details in the FAQ:

Automating Fan Control--Don't Use a Light Dimmer!

Continuing the discussion from Fan Light Dimming - Aeon Labs Aeotec Z-Wave Micro Dimmer: Thanks for the shout. Yeah, basically you need to read the manufacturer’s directions for the fan, and check that against the manufacturer’s directions for the dim control. Rate controls For home use are usually either TRIAC or VFD (Variable frequency drive). A TRIAC controller varies only the voltage. This is what’s typically used for a dimmer light because that’s exactly how you make the light brighter, you give it more voltage. A VFD varies both the voltage and frequency. But more importantly in this context, is how the dimmer knows to turn itself on. The short answer is the dimmer switch itself, if it uses a TRIAC, is very sensitive to changes in the voltage, and basically it can get confused …