Andy Morris has solved an aggravating problem. You can get a remote control for tower fans, but theyíre too noisy for the bedroom. Propeller fans are nice and quiet, but they donít come with remotes. So Andy devised a propeller fan remote control that does not require line-of-sight, which makes it easier to use in the dark.
The gadget comes with off/on, three fan speeds, and multicolored LEDs to indicate the fanís speed. As a bonus, it beeps to indicate that the fan got your message.
The design is well thought out and I have no doubt the gadget works as described, but it's a lot of labor to build. There are cheap commercial radio-controlled (300 MHz) appliance switches on the market that would at least turn the fan on and off. There are also 3-speed models using phase angle controllers for ceiling fans. I have one that cost <$20 and works just fine. There's no reason it wouldn't control a table fan just as well. All one would have to do is install it in a suitable box.
I also like to build stuff but generally do so when there is no economical solution already available.
You are quite right that there is fun and learning when you build stuff yourself, but I thought I answered that point in my last line. We do achieve those goals when we build things that we can't get off the shelf and there are plenty of such opportunities. At least for me as consultant I design and build numerous non-standard instruments both for my lab and my clients' facilities.
Putting the learning aspect aside, I'd like to point out that ceiling fans (very popular here in toasty Tucson, AZ) have a UL-approved solution available on most products. Hunter, Hampon Bay, Casablanca are some brands, There is a module inside the fan housing that receives an RF coded signal from the remote control. The module connects power to the fan motor's multiple windings, as well as to the light fixture which are often part of the ceiling fans. I never tried buying the control module separately, but it is worth trying before subjecting yourself to an uninsured loss, should, heaven forbid, your homebrew caused a fire. Using any "not to code" wiring or a home brewed control will void your fire insurance in case of a fire. Better hope you will never need it.
Tucsonics raises an interesting point. We've all heard stories of the excuses big insurance companies use to shoot down customers' claims.
The question, then, seems to be how directly the non-compliant gadget might have contributed to a fire (or other accident). Clearly if it is the direct cause then that could be grounds to reject the claim. But what if the device is connected to the house wiring (say in another room) and is clearly not the cause of the fire? What if a non-compliant device is simply sitting on a shelf in the house, not plugged in at all? Any clarification on the rules or conventions on this?
As for my radio fan control, I bought an after-market one and installed it in an exising ceiling fan. It does not switch between windings but uses a phase angle controller (probably a triac) to adjust the AC voltage to the fan whose original speed switch is permanently set to "high." It works quite well and it has a additional channel to switch and dim the light fixture attached to the fan. There is no technical reason why someone could not mount the receiver section in a box with a plug and an outlet to control a table fan.
The problem about insurance companies balking at covering fires when a non-standard gadget is hooked up to the house's wiring could apply to a wide range of gadgets we cover in Gadget Freak. Most of the gadgets are electronic and many connect to the house's wiring.
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