strange acting ceiling fan light


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Old 10-26-16, 03:18 AM
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strange acting ceiling fan light

Last night when I switched off the the ceiling fan/light I noticed that as the fan blade turned the bulbs would almost light up [momentary yellow glow] I also found out that with the switch off you can manually turn the blade and make the bulbs almost light up. Not a steady light but blink for a second or less.

The fixture receives power at the ceiling box, not at the switch. I haven't opened it up yet. Would it likely be just in the light cover or does the fan need to come down. Any ideas as to what is going on?
 
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Old 10-26-16, 04:57 AM
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What type of lights do you have? Incandescent, fluorescent or LED?

Incandescents take a fraction of a second to cool so you'll briefly see the light dimming rapidly, but I'm sure you used to seeing that. If the room is dark the phosphors in fluorescent lights will continue to glow for a surprisingly long time. LED's usually go right out but I have seen some do some flickering as their power supplies drain.

It's possible the ceiling fan motor is acting like a generator. The inertia of the fan blades keeps it turning for some time and some of that energy gets converted to electricity. I don't think it would be enough to light incandescent lights but it might give an LED or fluorescent some life.
 
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Old 10-26-16, 05:05 AM
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Are they flickering or glowing? Flicking would mean a loose connection in the fan box, does the switch control both the fan and light?do the lights get brighter when the blades are spun faster?
 
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Old 10-26-16, 05:13 AM
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It has incandescent bulbs. There is one switch that controls the fan/light using the pull chains to change fan speed and the light. If you spin the blade [with unit off] the lights will come on - not fully, more of a flicker every few seconds. How fast you spin the blades doesn't seem to affect the brightness. The lights don't fully come on, just kind of a momentary yellow glow. When I first saw it I thought my mind/eye was messing with me but I found I can duplicate by spinning the blade. Never noticed it before last night.

It's a ceiling hugger fan that was installed 12-15 yrs ago.
 
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Old 10-26-16, 06:27 AM
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Ok, now I can't make the lights come on when they are switched off
I guess I'll just keep an eye on it.
 
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Old 10-26-16, 09:28 AM
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If they just dimly or very briefly flicker on I'd look for a loose connection. Does tapping/banging on the fan make the lights flicker?
 
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Old 10-26-16, 09:49 AM
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The lights would come on just for a millisecond as the fan rotates. The bulbs would try to light up every few revolutions of the blade. It's no longer doing it so I can't test any theories.
 
 

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