LED bulb bleeding

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Old 11-15-11, 05:48 AM
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LED bulb bleeding

My hallway light fixture uses 3 of the smaller screw-in bulbs. I just installed 3x2 Watt LED bulbs. Even with the switch "off" the bulbs glow at a very, very low intensity (you can barely see the diodes). If I unscrew the bulb then the light goes out completely indicating there is some power leaking to the bulb when it is screwed in. A) Is this normal? B) Should I / Can I stop it? C) Should I check all electrical connections for some type of leakage?
-Thanks as always!
 
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Old 11-15-11, 06:18 AM
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A lighted switch or timer switch that uses no neutral will do this. Do you have either of that type of switch?
 
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Old 11-15-11, 06:26 AM
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No lighting or timer in the switch. It would be a totally basic light switch except that it is at the top of the stairs so there is one light switch at the bottom and one switch at the top of the stairs that controls this fixture. Any other thoughts?
 
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Old 11-15-11, 07:29 AM
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LED lamps can glow with VERY little current, much less than rated current. What this means is that even the wiring itself can capacitively couple enough energy into the "OFF" circuit to give some lumen output. The easiest way to fix this is to put in one incandescent bulb in that circuit, even a very low power one, like a night light type bulb. Other, more difficult options are using a double pole switch at the wall, the other much harder way is to route the wiring away from other circuits.
With the 3-way switches that you have, the energized "traveler" is coupling that energy to the wire that connects to the bulb, through a long-ish run of 14-3 wiring, more than likely. The only reasonable solution is to replace one LED with an incandescent.
 
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Old 11-15-11, 07:51 AM
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So would I change both wall switches to double pole or just one of them?
 
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Old 11-15-11, 08:13 AM
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Originally Posted by knothandy View Post
So would I change both wall switches to double pole or just one of them?
That would be problematic, with the stairway situation. I don't know of a 3-way, double pole switch, maybe someone else here has used one. You would need to break the neutral conductor as well as doing the normal 3-way switch option. The switch boxes might not even contain the lamp neutral. THat's why I'm saying in your case, using a single incandescent bulb and continuing to use the remaining 2 led, might make sense.
 
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Old 11-15-11, 08:23 AM
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A double pole switch might be a code violation because you are interrupting the neutral. Really don't know for sure.
 
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Old 11-15-11, 09:19 AM
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The neutral cannot be switched.
 
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Old 11-15-11, 10:11 AM
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Originally Posted by pcboss View Post
The neutral cannot be switched.
Yes, this is correct. 404.2 says 3 and 4 way switches can only work on the hot side. It further reads that you can switch the grounded conductor only if you also switch the hot side, presumably not a 3 or 4 way switch. So, that could work in a single switch situation, which the OP does not have.
 
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Old 11-15-11, 10:49 AM
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I exchanged one of the 2W LEDs for a 4W CFL and that stopped it from glowing. I checked with a little incandecent night light and that worked too. Still wish there was a way to fix it at the electrical connections but I guess it's just a physics thing.
 
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Old 11-15-11, 11:13 AM
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Originally Posted by knothandy View Post
I exchanged one of the 2W LEDs for a 4W CFL and that stopped it from glowing. I checked with a little incandecent night light and that worked too. Still wish there was a way to fix it at the electrical connections but I guess it's just a physics thing.
Yeah, I hear ya. Let's just say that when 3-way circuits were "invented", 2 milliamp leakage currents lighting up lamps were not even dreamed of! There are ways to add a small parallel load inside the fixture, but I can't recommend that to a homeowner to experiment with. I do believe that led dedicated fixtures will need to address the issue at some point.
 
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Old 11-15-11, 11:15 AM
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knothandy and telecom guy,
Is this apparently in the same category as the phantom voltages people see on their digital meters, where the voltage is really there but it is simple an extremely low level of inductive energy? Apparently these new LEDs seem to be able to run ever so slightly on that energy. As knothandy said, shame we have to waste a bit of energy to be able to use these new energy efficient lights.

Telcom, I'm interested in what steps we could take with new construction to be sure this problem doesn't affect various new lighting options to come. Any thoughts?

Bud

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Old 11-15-11, 12:18 PM
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Originally Posted by Bud9051 View Post
Is this apparently in the same category as the phantom voltages people see on their digital meters, where the voltage is really there but it is simple an extremely low level of inductive energy?
Yep, exactly the same effect.

Apparently these new LEDs seem to be able to run ever so slightly on that energy. As knothandy said, shame we have to waste a bit of energy to be able to use these new energy efficient lights.
The energy is wasted with traditional bulbs too, they just don't glow enough to be visible.

I'm interested in what steps we could take with new construction to be sure this problem doesn't affect various new lighting options to come. Any thoughts?
One obvious thought is that current lighting circuits are vastly overbuilt for LED using 15A line-voltage circuits. LED-only circuits could be installed using low-voltage digital signalling instead of line-voltage switching. With this approach it would only be necessary to wire switches using some type of communication cable instead of romex. Another option in some cases is to eliminate n-way switches altogether and use occupancy sensors, timers, remote controls, and similar devices. The problem with many alternative approaches is that you still have circuit requirements to satisfy code.
 
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Old 11-15-11, 01:51 PM
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Originally Posted by Bud9051 View Post

Telcom, I'm interested in what steps we could take with new construction to be sure this problem doesn't affect various new lighting options to come. Any thoughts?

Bud

Slow typing
Lutron has a product called HomeWorks. I saw an install a couple of months ago, that integrated LED/CFL lighting products with "mood" control, timers, occupancy sensors, and ventilation. The flush-wall control box was at least the size of my 42 slot load center. I saw lots of Cat5 cable run, but I'd have to read more to see if it was all Cat 2 low voltage wiring. I suspect a lot of the fixture wires were low voltage. Once a control standard becomes viable, I think the builders will start to embrace such a system.
 
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Old 11-15-11, 08:36 PM
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Until we start switching over to a digital signalling type system, I wouldn't worry about the slight glow. The power that it's using is incredibly small, even when compared with 'vampire' power used by electronics when they are off. I'm sure someone could do the math, but I'd think it would be in the order of pennies per year, if that much.
 
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