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LED Christmas lights

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Oliver Hardy

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Nov 19, 2009, 7:22:37 PM11/19/09
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I have hooked up a string of LED Christmas lights to an x10 appliance
module as a test. They turn on fine but when they turn on they are
still on, but very dim. Any reason why this should happen? I thought
Appliance modules mechanically cut the source power.

Robert Green

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Nov 19, 2009, 7:56:25 PM11/19/09
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"Oliver Hardy" <oli...@hardy.com> wrote in message
news:q4obg5tpt6nu0vq3k...@4ax.com...

Nope - appliance AND lamp modules trickle current through the string for
"local sensing" (which allows the modules to turn on by jiggling a lamp's
built-in switch) and that makes the phantom glow. It's also the culprit
behind the flashing (and relighting) of CFL bulbs that are run on appliance
modules.

There are various circuit mods (usually involving cutting a trace or a
component lead in the module) you can try that are pretty simple but of
varying effectiveness, or you can add a small tungsten string or nightlight
bulb to the load. This very often stops the phantom glow.

IIRC, Smarthome made a module that allowed you to programmatically disable
"current sense switching" that would also eliminate the problem. I've also
had some luck piggybacking modules so that it would take two commands to
light the string. Plug a module set to A2 into a module set to A1 and then
it would take A1 ON, A2 ON to light the string. IIRC, it's not a guarantee.

I just got a new string of LED lights, so I'll give it a try and let you
know.

--
Bobby G.


Mike Barnes

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Nov 20, 2009, 4:00:05 AM11/20/09
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Robert Green <robert_g...@yah00.com>:

>"Oliver Hardy" <oli...@hardy.com> wrote in message
>news:q4obg5tpt6nu0vq3k...@4ax.com...
>> I have hooked up a string of LED Christmas lights to an x10 appliance
>> module as a test. They turn on fine but when they turn on they are
>> still on, but very dim. Any reason why this should happen? I thought
>> Appliance modules mechanically cut the source power.
>
>Nope - appliance AND lamp modules trickle current through the string for
>"local sensing" (which allows the modules to turn on by jiggling a lamp's
>built-in switch) and that makes the phantom glow. It's also the culprit
>behind the flashing (and relighting) of CFL bulbs that are run on appliance
>modules.
>
>There are various circuit mods (usually involving cutting a trace or a
>component lead in the module) you can try that are pretty simple but of
>varying effectiveness, or you can add a small tungsten string or nightlight
>bulb to the load. This very often stops the phantom glow.

Or you can just live with it. There's no danger, and negligible cost,
involved.

--
Mike Barnes

John Perry

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Nov 20, 2009, 6:36:25 PM11/20/09
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We have some of our home lights wired up with two on/off switches, so
the lights are off when either both switches are off or both on.

If we leave the switches both on, the lights should be off, but they
is sufficient induced voltage in the wiring to leave the LED lights
very very slightly on! These are LED GU10 lights normally running at
230V AC.

LEDS are so efficient, they need very very little current to produce a
little light.
--
John Perry

http://www.redoak.co.uk

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