Lamp module causes noise??

[mike2711@yahoo.com]

I finally got my Elk Meter and realized that I had virtually no signal
in my living room/den circuit, with a substantial amount of noise. I
finally traced it to a brand new Radio Shack branded lamp module. I
replaced it with a Radio Shack branded appliance module, and now the
signal is strong and the noise is gone! Is this normal? Aren't most
modules the same just branded differently?

[Jack Ak]

<mike2711@yahoo.com> wrote in message news:1133288746.310848.133630@f14g2000cwb.googlegr oups.com...
> I finally got my Elk Meter and realized that I had virtually no signal
> in my living room/den circuit, with a substantial amount of noise. I
> finally traced it to a brand new Radio Shack branded lamp module. I
> replaced it with a Radio Shack branded appliance module, and now the
> signal is strong and the noise is gone! Is this normal? Aren't most
> modules the same just branded differently?
>

All X10 Lamp Modules will put noise on the power line. The 60Hz waveform
is "chopped" to enable dimming.

[mike2711@yahoo.com]

Thanks Jack! I figured since it was a "lamp" module that could
dim....that it might be the reason for the noise but should the noise
be at the 120khz PLC level? Plus it nearly absorbed the X10 signals on
the entire circuit when in the "on" position. I mean the Elk couldn't
read a valid X10 signal at all! Thanks!

[Dave Houston]

A lamp module should neither put excessive noise on the line nor eat all
120kHz. What was the load? Some CFLs are known to put noise on the line and
others are known to eat 120kHz.

A lamp module will put a short switching transient on the line. This usually
consists of about 8-10 cycles of ~150kHz that decrease from 10 or more volts
to near zero in about 75-100µS.

You can see an example at...

http://community.webshots.com/photo/506490147/506490147qmqcRj

This will not register on the ESM1.

mike2711@yahoo.com wrote:

>Thanks Jack! I figured since it was a "lamp" module that could
>dim....that it might be the reason for the noise but should the noise
>be at the 120khz PLC level? Plus it nearly absorbed the X10 signals on
>the entire circuit when in the "on" position. I mean the Elk couldn't
>read a valid X10 signal at all! Thanks!

[Dave Houston]

Ooops! The "75-100µS" had a misplaced decimal. It should be 7.5-10µS.

nobody@whocares.com (Dave Houston) wrote:

>A lamp module should neither put excessive noise on the line nor eat all
>120kHz. What was the load? Some CFLs are known to put noise on the line and
>others are known to eat 120kHz.
>
>A lamp module will put a short switching transient on the line. This usually
>consists of about 8-10 cycles of ~150kHz that decrease from 10 or more volts
>to near zero in about 75-100µS.
>
>You can see an example at...
>
>http://community.webshots.com/photo/506490147/506490147qmqcRj
>
>This will not register on the ESM1.
>
>mike2711@yahoo.com wrote:
>
>>Thanks Jack! I figured since it was a "lamp" module that could
>>dim....that it might be the reason for the noise but should the noise
>>be at the 120khz PLC level? Plus it nearly absorbed the X10 signals on
>>the entire circuit when in the "on" position. I mean the Elk couldn't
>>read a valid X10 signal at all! Thanks!

[mike2711@yahoo.com]

Hi Dave! It was controlling 1 string of christmas "mini lights", 100
bulbs. When the christmas lights were plugged in directly, no noise and
no signal loss. When plugged into the lamp module and in the "on"
setting, noise was present as well as very little signal (if any)! They
are now plugged into an appliance module without any problems...

[Dave Houston]

Do you see the noise with nothing plugged into the lamp module?

mike2711@yahoo.com wrote:

>Hi Dave! It was controlling 1 string of christmas "mini lights", 100
>bulbs. When the christmas lights were plugged in directly, no noise and
>no signal loss. When plugged into the lamp module and in the "on"
>setting, noise was present as well as very little signal (if any)! They
>are now plugged into an appliance module without any problems...

[mike2711@yahoo.com]

Yes!

[Dave Houston]

mike2711@yahoo.com wrote:

>Yes!

If the noise goes away when you unplug the module you have a defective lamp
module.

[mike2711@yahoo.com]

Hi Dave! Thanks for all the informative posts over the last few weeks
while trying to get this X10 project under control.... I posted a
question before that went unanswered regarding a keypadlinc that
somehow shuts off a device on it's own! It is a keypadlinc 6 with a
built in dimer. The dimmer is controlling my porch lights, while the 4
middle buttons control other exterior lighting as well as my landscape
transformers that are mounted in my garage. The transformers (plugged
into X10 receptacles) are controlled by a Leviton 6308 photocell
mounted on the outside of my house, but is very flaky (that is another
problem I'll relate below). When it works, it turns on the transformers
at dark, turns on the status indicator on the keypadlinc, then turns
them off at dawn, and the status indicator goes off. BUT about every
other night, the transformers turn off by themselves after a few hours.
Sometimes the keypadlinc status light remains lit, when the
transformers turn off prematurely. I have had the Leviton 6308
controlling the transformers for a couple years, with varying degrees
of success, but they never turned off by themselves until I installed
the keypadlinc. It isn't stray signals from neighbors because I tried
multiple house and unit codes and the behavior is the same! I have
tried it with "boosterlinc" enabled and disabled, no difference.
"Boosterlinc" is currently disabled. *Problem 2* The reason I installed
the keypadlinc in the first place was to have a way of controlling the
transformers easily since the Leviton 6308 wasn't turning on and off
the transformers reliably on a daily basis. I have determined that the
Leviton 6308 is sending a strong signal every time as evidenced by my
Elk meter. The Leviton 6308 and the X10 receptacles that control the
transformers are on the same circuit. They get strong, robust signals
every time. I turned on many appliances, lights, tv's, space heaters,
etc. to try and determine if any noise is generated.....no difference,
a very strong signal! I let my furnace cycle 3 times while watching the
Elk meter, no noise. I continually sent commands with the furnace
cycling, no problem, strong signal! I also duplicated the electrical
state the house is in the morning, no lights, 3 space heaters going and
the furnace cycling, still a strong signal! I'm at a loss and am ready
to buy Intermatic astronomic digital timers to control the transformers
and just simply take the transformers out of the X10 equation... The
Elk meter did show that I have a phase coupling issue, it is a 3000 sq
foot house BUT the Leviton 6308 and the transformers are on the same
circuit!! HELP!!!