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

["Robert Green" <ROBERT_GREEN1963@xxxxxxxxx>]

"AlanTinNYC" <AlanTinNYC@xxxxxxx> wrote in message


<stuff snipped>

> 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.

My experience with Leviton's tech support was SO awful I would buy *any*
competitor's product first.  I got the impression that they would tell
customers anything just to get them off the line.  As for answering tech
emails - well, it never happened.  One of their employees appeared briefly
here a while back and confirmed a certain uniformity in their hiring
process.  Rude certainly fits like a glove. Maybe you'll have better luck,
Bubee.

In your case, the situation is so complex that diagrams and explanations are
required.  That's probably not going to happen with a Leviton phone tech.  I
was never able to get an answer to my emails so I can't comment on their
online support other than to notice its total lack thereof.

> 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 you really don't know whether you have solved the problem or whether the
mystery noise source has shut down for some reason, correct?  This is why I
think going with a repeater so soon is a bad idea.  If there's noise so bad
that it makes X-10 devices respond unbidden, then it's likely the noise is
going to affect the repeater adversely, too.  Besides, responding to a
second copy of a command is never as good as responding to the first one.
First off, it introduces a time delay - slight but noticeably.  Secondly, it
defeats the idea of sending two copies for redundancy.

If you can possibly do it, clean up your own wiring of any signal suckers,
surge protectors, UPSs, switching power supplies for laptops, printers,
etc., or anything else likely to "soak up" or otherwise impede X-10 signals.
It means a lot of time at the breaker panel and running back and forth to
outlets, but the only way to find these problem devices is to switch off all
the breakers except the test transmitter and the meter and then turn the
breakers back on one by one and watching the meter.

> 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.

I'd been SO wary of adding more shmatteh to the system before I understood
the underlying issues.  KISS.  It works SO well.

> Much of the time, the controller works fine, but when I'm metering
> sustained, stray 120kHz activity it doesn't work.

You don't need two repeaters - at least not yet (especially hinky
HCA02-10E's), until your are SURE you have blocked your apartment wiring
from the rest of the world.  Until you take that step, your powerlines are
at the mercy of whatever your neighbors are plugging in.  No solution that
leaves your home "powerline grid" vulnerable to outside PLC signals is going
to keep the noise and perhaps other tenants X-10 signals from getting in.
That's about as plain as it gets.

 > 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.

Yep.

> 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"?

It should, but that advice is mostly for single family homes.  I still don't
know what your wiring looks like, and were it my apartment I would be
crawling all over it with an ESM-1, a Monterey PSLA and a fox and hound wire
tracer set to understand where EVERY outlet goes to and what the signal
attenuation looks like.

To do this I set up a TM751 in an outlet next to the  circuit panel and then
send it continuous signals from a transmitter with a purposefully jammed
button.  Then I go all over the house looking at the signal strength at
various outlets.  From their, I get a pretty good idea of what branches are
problematic.  Also, from there, I can shut off one leg of the house wiring
after another to find circuits that contain suckers or other X-10 signal
traps. A very long extension cord helps.  You can plug the meter into almost
any outlet in the house with it and still read it back at the panel(s).
You'll probably be as surprised as I was to see how little voltage is lost
on a run of 100' of extension cord.  It was a good reminder that the problem
is usually a few devices scattered throughout the home that are either
generating noise or otherwise interfering with X-10 signals.

> 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.

Ever consider that God knows you're cheating by using an electronic shabbos
goy?  Maybe that's why you are having so much tsores getting rid of your
electronic dybbuks!   www.shabot6000.com


> 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.

Dave's Insteon suggestion sounded very good.  You can phase couple via RF
inside Faraday cages, if necessary.

There's no certainty that you can eliminate the noise.  Like Dave, I've had
periods where the ESM-1 shows high noise levels for days, and then nothing.
The only hope to straighten your mess out is to KISS and solve one problem
at a time.

Adding amplifiers and repeaters into a noisy environment isn't the right
solution from the start.  If you are dedicated to using X-10, you'll have to
understand your apartment wiring completely.  Are you near any radio or TV
broadcast towers.  I recall reading about someone with a similar problem in
the archives.  Apparently a nearby transmitter can put serious noise on the
line via induction.

> 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.

That's only if you want your conflicting advice in writing.  :-)

> 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?

You either have to filter it or find some other control topology.

> 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?

Dan and Dave have explained why that's not feasible.
>
>
> That's where things stand.  Given my workload and the upcoming
> holidays, I don't think I'll be getting to this until 2006.

Optimist.  Very few X-10 installations are *ever* finished.  There's always
some bug or intermittent operation or failure to contend with.  But it's the
cheapest thing on the market AND the most universal.  We'll see if that
continues.

Good luck!

--
Bobby G.