Re: Need help with PLC noise problems in a Manhattan (New York City) apartment

[nobody@xxxxxxxxxxxx (Dave Houston)]

I still think you need one PZZ01 _assuming_ that you can put that one
upstream of the 2B-2C split. Are there separate feeds from the basement to
the 2B & 2C panels?

I'm also a bit puzzled by how the 6825 works. It would really help to see a
schematic. The effects of a signal sink are somewhat localized because of
the impedance of the wiring itself but I don't quite understand how a 6825
can attenuate alien signals without also attenuating legitimate signals
trying to go from 2B to 2C.

My earlier recommendation of two HCA02-10Es was based on...

http://www.worthingtonsolutions.com/activekb/index.php?ToDo=view&questId=25&catId=5

Two ACT CR234s are probably a better choice because of the SCC feature.

With X-10, one other thing might help. The LM14A lamp modules and (I
suspect) the Leviton switches that respond to extended codes do a better job
in the presence of low level 120kHz noise than do LM465 lamp modules and
X-10 made switches. However, we still don't know the amplitude of the 120kHz
noise you are seeing.

The repeating couplers do not repeat all 120kHz and they don't really
amplify (at least those made by ACT don't) but merely repeat the X-10 signal
during the time frame for the second copy of the X-10 command.

I still think this might be a situation where Insteon would work far better
than X-10. It might be unaffected by the 120kHz noise. You only need RF
communication between the RF links which act to bridge the phases. You
should be able to locate these near each other, perhaps even putting them
inside a Faraday cage to prevent external RF from jamming them. You may need
four RF links.

"AlanTinNYC" <AlanTinNYC@xxxxxxx> wrote:

>No, I'm not confused, but I just got very busy with my day job and came
>down with a minor illness, so I couldn't follow up for a while.
>
>After considering everything, and after both my electrician and I tried
>to discuss this with Leviton on the phone (their expert was a bit
>rude), I think the next step is to write to Leviton (I have a
>friendlier tech's e-mail address) including some of the detail I wrote
>to this group and ask for a better explanation or description of their
>product.
>
>Our lights are no longer going "crazy." They do occasionally shut down,
>about once an evening, not three times an hour, and they no longer
>spontaneously switch on.  But they are not yet steadily controlled by
>the CM15A, probably because we do have the attenuators installed
>(improperly, I fear) and don't yet have the HCA02-10E's installed.
>Much of the time, the controller works fine, but when I'm metering
>sustained, stray 120kHz activity it doesn't work.
>
>
>Considering everything so far...
>
>1)  Yes, I do want/need a "firewall" so to speak, although I understand
>such a device would not digitally block all unwanted stuff  (as a
>computer network firewall would) but attenuate it by absorbing it (as
>does the 6825) or phase-cancel it (as does the 6824 or PZZ01) down to
>tolerable levels.
>
>
>2)  Acknowledging that "X-10 is decades old.  The designers just
>couldn't foretell how much things would change in 20+ years...," then
>unless the incoming noise levels are EXTREMELY high (greater than the
>30:1 attenuation provided by the Leviton filters), wouldn't the proper
>application of hard-wired filters on my panels combined with plug-in
>filters on my own noisy appliances protect the network against this,
>without a need to "generate your own power and disconnect from the
>grid"?
>
>
>3)  I'm just too wary of RF solutions in the Big City.  And what is
>likely to happen to any RF network's integrity in a few years?  Didn't
>we all love our 2.4GHz cordless phones until wireless home network
>routers came out?  I don't use the RF function in the CM15A; I just use
>it as a whole house Sabbath timer (well, technically, half a house,
>since I'm isolating my two service panels and will ultimately use two
>controllers).  I have the RF function on my CM15A shut off except
>during testing.
>
>Or should I trash my PLC system, go with RF and plan on trashing *any*
>home control network every 10 years or so because we "just can't
>foretell how much things will change"?
>
>I propose to this group that "new" isn't necessarily better, "old"
>isn't necessarily archaic or obsolete so long as we have the network
>integrity protected.  That could mean building an effective PLC
>firewall, or it could mean encasing my home in concrete and lead to
>shield it against anything stray flying through the air.  I prefer to
>filter just the wires.
>
>
>4)  I just don't "get" how the 6285 attenuator is supposed to work.  If
>it is supposed to knock down everything flowing through my house at
>around 120kHz, then why does my unamplified controller work during
>non-noisy times?  And if it installs on two 15 Amp branch breakers (as
>per the written instructions), then how does it block my neighbor's
>noise from flowing from the main feeds onto the other branches in my
>panel?  (Please see my earlier illustration.)  Is it an effective
>"signal sucker," sucking everything at the panel?  If not, what
>protects my WS12A dimmers on the other branches the 6285 isn't wired
>to?  If it is an effective signal sucker, why wouldn't it take care of
>my noisy PC monitor or other devices (every "laptop, UPS, shaver,
>battery charger, CFL, dimmer, etc.") as well?
>
>But I'm speaking hypothetically now.  I'm not getting the 6285 to
>perform consistently, so I think it's not properly -- or effectively --
>installed.
>
>When speaking with Leviton last week, the first tech said we should
>connect the 6285 "as close to the incoming feed as possible." That
>meant connecting it to two separate 15 amp breakers, each breaker the
>first in line on its phase, and suggesting that this could block
>incoming noise from trickling to other branch circuits.  But then the
>"specialist" who took over the call practically barked, "No, I don't
>want this on two separate breakers.  I want this on a single,
>double-pole breaker!"  So much for placing the filter as close to the
>incoming feed as possible... Time to write to Leviton.
>
>
>5)  Before I sink in an additional $85 for each of two HCA02-10Es (and
>possibly knock holes in my plaster & lath walls for the boxes to house
>them), I want to know that they will be effective.  Does it boost all
>120kHz activity?  Won't that put me back where I started?  Does it
>"recognize" clean X10 code separate from noise?  How?  What happens
>when a clean X10 packet collides with noise?  We already know that X10
>won't work when two good packets collide.  While I can get around
>some packet collisions by programming the CM15A to repeat commands,
>what do I do to get around 3 - 4 hours of sustained noise?
>
>Can't one just amplify the output of a controller before it plugs
>into the powerline?  That would introduce X10 signal at several volts
>onto a powerline network where all 120kHz activity is then attenuated
>by a whole house filter.  Does anyone make such a feed-thru amplifier?
>
>
>
>
>That's where things stand.  Given my workload and the upcoming
>holidays, I don't think I'll be getting to this until 2006.
>
>
>Merry/Happy whatever-you-celebrate, everybody!
>
>
>-- Alan