Non-dimmable LED + dimmer = Bizarre Behavior


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Old 02-28-18, 03:55 PM
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Non-dimmable LED + dimmer = Bizarre Behavior

One of my tenants replaced an incandescent bulb with a non-dimmable LED in a 5 bulb fixture connected to a dimmer. When the dimmer was all the way off the LED stayed on. When the dimmer was turned on, the LED flashed. The tenants don't speak English well so I'm not entirely sure what the incandescents were doing, and when I got there the only working bulb was the LED. They also claimed that some of the bulbs exploded.

I replaced the non-dimmable LED with a dimmable one and found a couple of working incandescents, so everything is OK for now, but clearly there is more to it. For the LED to shine at all when the dimmer was off must mean that the dimmer is leaking some amount of juice even in the full off position. But what about the exploding bulbs? What might be the explanation for that?
 
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Old 02-28-18, 04:32 PM
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For the LED to shine at all when the dimmer was off must mean that the dimmer is leaking some amount of juice even in the full off position.
Yes.... that is very possible. Sometimes the LED's stay on dim just from the way the circuit is run. Using a dimmer rated for LED's would be a step in the right direction.

As far as exploding LED bulbs.... I have no idea. I've never had any explode on me.... even using the incorrect dimmer.
 
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Old 03-01-18, 05:40 AM
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In my rental houses light bulbs "explode" when children are left unattended at home. I'm not saying they were playing ball in the house but I have never had a bulb ever explode in my house, parents house, my business warehouses, factory or anywhere for that matter...
 
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Old 03-01-18, 09:08 AM
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Sometimes the LED's stay on dim just from the way the circuit is run.
Some electronic dimmers (especially remote controlled) will use a small "leakage" current to keep the controls active. It is not enough to light an incandescent bulb, but it will light an LED. Having an incandescent bulb on the same switch eliminates the problem.
 
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Old 03-01-18, 09:11 AM
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Originally Posted by PJmax
Yes.... that is very possible. Sometimes the LED's stay on dim just from the way the circuit is run. Using a dimmer rated for LED's would be a step in the right direction.

As far as exploding LED bulbs.... I have no idea. I've never had any explode on me.... even using the incorrect dimmer.
PJmax, when you say, " Sometimes the LED's stay on dim just from the way the circuit is run," what do you mean by that? I would think that any light switch or dimmer should stop ALL power to the fixture. Where would the LED be getting its power from?

I suspect the "exploding bulb" thing is a translation error.
 
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Old 03-01-18, 10:33 AM
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I think 2john02458 answered my question, and I suspect my dimmer is leaking current. I noticed when I pulled it out that there was a lot of roach poop. Maybe that's what is letting the current get through.
 
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Old 03-01-18, 11:33 AM
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It doesn't have to be a leaky dimmer. You could pull it out and still have the LED's lit dimly. LED's need very little power to operate. They can light dimly just by having the wiring that runs to the light.... next to an always live cable. The voltage is induced onto the dead cable from the live cable with no physical connection.
 
 

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