Traditional dimmer and clear glass dimmable LED

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Old 11-02-20, 08:54 PM
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Traditional dimmer and clear glass dimmable LED

My friend have a ceiling fan mounted high up in the ceiling (about 20ft high) with remote control receiver. It has dimmer function as with most ceiling fan remote. Since it is a old fan, the dimmer circuitry is made to work with incandescent bulb only. Replacing the receiver will require scaffolding.
I tested a standard dimmable led bulb (ones with LED driver) and as expected the bulb just flickers. I know using non-compatible dimmer with this type of LED bulb will fry LED driver from my past experience. So, I tried clear glass dimmable LED bulbs, which has COB LED sticks connected in series instead of using LED driver. It worked and dimmer function also worked although it has very limited range of dimming (pretty much same full brightness until almost at the bottom).

Now, the question is will there be any problem down the road other than dimmer function is pretty much useless?
Any one have long term experience?
 
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Old 11-02-20, 11:55 PM
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There is a real good chance leaving the LED's attached to the receiver will cause the dimmer to fail.
I've seen it happen many times.

The LED's present a short to the dimmer circuit and it can cause the triac to fail.
 
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Old 11-03-20, 04:39 AM
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You may think a glass LED bulb is different but they are all basically the same with similar electronics and C.O.B emitters. If your friend is considering an upgrade or remodel of the room this would be a good time to consider a new ceiling fan the accommodates LED bulbs, or you can replace the dimmer control module.
 
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Old 11-03-20, 06:30 AM
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An LED bulb is constructed of hundreds of individual diodes. The individual diode will only emit light when the voltage is the correct polarity. The individual diodes may be connected in series, parallel or a combination of both depending on the LED bulb manufacturer. LED bulb electrical operation is not affected by envelope material. Only use dimmers recommended by LED bulb manufacturer.
 
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Old 11-03-20, 05:11 PM
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You may think a glass LED bulb is different
LED bulb electrical operation is not affected by envelope material.
Well, the difference I know for sure is that these glass LED bulbs do not use LED driver circuit to drive LEDs. I'm sure that makes a huge difference in operation of dimmers.

The LED's present a short to the dimmer circuit and it can cause the triac to fail.
This is the answer I was looking for and was kinda worried about.
With traditional dimmer set to full brightness, will that still cause triac to fail? I'm sure triac is still switching even at the maximum brightness, but I wonder if that would still be enough to cause triac to fail.

Guess when the controller fails, she will have no choice but to replace anyway..
 
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Old 11-03-20, 05:14 PM
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Some of those "old fashion" looking bulbs used series strings of LED's and a possible resistor or two.
I don't know if they will affect the dimmer in the same way.

As you mentioned there is no driver and that's what usually causes the problem.
 
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Old 11-03-20, 05:46 PM
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As you mentioned there is no driver and that's what usually causes the problem.
So, basically using non compatible dimmer on LED bulb with driver fries LED driver, and using LED bulb without driver fries the dimmer.

Home with high ceiling are stupid.. They are nice only until you need to change a bulb or the light fixture.
 
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Old 11-03-20, 05:49 PM
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My point is..... it's the driver in an LED bulb that presents the short to the dimmer.
If there is no driver..... you should be ok.
 
 

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