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

[nobody@xxxxxxxxxxxx (Dave Houston)]

I have no idea what the 6285 actually does and was unable to find any
detailed description. SmartHome's and Leviton's descriptions imply that it
blocks signals from passing but the connection scheme doesn't appear to
support that. If it merely attenuates 120kHz there is no way it can
distinguish between your valid signals and external "noise" (i.e. a rose is
a rose is a rose).

http://www.leviton.com/pdfs/dhctechman.pdf

Insteon only uses RF to couple the two phases. That might cause problems in
your environment (especially since they use a fixed frequency) but if it
does not, it's other features would likely be highly beneficial in your
situation. It will ignore signals from devices which you have not "enrolled"
so external Insteon signals would not be a problem. It has good noise
immunity. It will not resend forever but only for a fixed number of tries.
The signal packet duration is brief. If you have time, read the Insteon
whitepaper on the Insteon site.

http://www.insteon.net

If you haven't already invested heavily in X-10 it would be an ideal time to
investigate Insteon. (more below)

You are misinterpreting the TesterLinc output. It does not measure the
amplitude (i.e. level) of a signal but merely counts cycles within an
unspecified window just after zero crossing (ZC). X-10 says the receive
window extends from ZC+250µS-ZC+900µS and that 48 cycles in that window
constitutes a logical Manchester 1. For transmitters they recommend the
120kHz burst begin as soon as possible after ZC but no later than ZC+100µS
and continue to ZC+1ms. That means there should be anywhere from 108-120
cycles in the 1ms following ZC with up to 78 cycles within the 650µS receive
window. SmartHome does not specify where the TesterLinc window starts/ends.
Nor do they specify the sensitivity (i.e. minimum amplitude). I don't think
there is anyway to correctly interpret its output without knowing those
details.

I would suggest you get a loaner ESM1 from Martin Custer at AutomatedOutlet.
It will tell you the amplitude of the signals and noise. While its bandwidth
is not quite as wide as older X-10 receivers it is much wider than that of
the TesterLinc.

http://www.automatedoutlet.com/product.php?productid=463&cat=0&page=1

I also suggest that you email or phone Martin and ask if you can return an
Insteon starter kit if it turns out that it will not work in your
environment. If Insteon can make it there...

"AlanTinNYC" <AlanTinNYC@xxxxxxx> wrote:

>Thank you all for your guidance.  To answer some questions/comments:
>
>1)  I'm not an electrician or electrical engineer, but
>    I am an audio visual engineer working in Manhattan
>    for 20+ years now.  My gut feeling when I saw
>    Robert Green's RF recommendation is that in this
>    city I don't trust wireless *anything* -- too many
>    glitches in both old, tested technologies (wireless
>    microphones) to new ones (Nextel GPRS) .  We just
>    have too much traffic to keep a local RF system
>    reliable.
>
>    I thank Dave Houston for concurring on that, but
>    he asks about Insteon.  Isn't Insteon half RF-
>    based?  That's why I opted for a more "tried and
>    true" X10 solution; we even tested an X10 dimmer
>    in our old apartment four blocks away in the same
>    neighborhood and had flawless results for two
>    months.  I've since learned the hard way that the
>    two buildings are not analogous.  :-(
>
>    The other point about Insteon, I think, is that
>    it continues sending a command until the receiving
>    device acknowledges it.  That might mean that
>    during a long noisy period we could see the
>    command execute a few hours after it was given.
>    But I'm speculating here; I have no hands-on
>    experience with Insteon.
>
>
>2)  I simplified the description of my apartment's
>    environment in my last post ("That was SIMPLE,
>    Alan???")  It's not just two adjoining apartments
>    with a wall knocked down but in fact underwent a
>    gut renovation.  Every old branch circuit was
>    severed, new lines were run through new walls,
>    with new switches, outlets, etc., and one of the
>    service panels was upgraded.  I think the mains
>    wiring from the basement cutoff breakers may date
>    from 1941 but I doubt it; the feeder cable seems
>    to be PVC insulated.
>
>    So if we are cross-linked with any neighbors, this
>    would happen before service reaches our apartment,
>    as all our branch circuit wiring is new.
>
>    But if we are indeed cross-linked with our
>    neighbors before the service enters our panels,
>    wouldn't a whole-house block or attenuator stop
>    or greatly reduce that?  Otherwise, what purpose
>    do those devices serve???
>
>3)  When I speak of our lights randomly flickering on
>    or off (I chose the wrong word; they don't
>    "flicker" but do switch on or off); I did mean
>    RANDOM:  there is no recognizable time or
>    pattern, i.e., they don't turn off right after
>    going on, or vice versa.  It just happens when it
>    happens; most of the time I can run over to the
>    TesterLinc and see high 120kHz activity but no
>    valid X10 codes (lots of bad blocks, though).
>
>4)  When I wrote of "good isolation" between our two
>    service panels, I used the signal generated by our
>    Active Home Pro (CM15A) and the TesterLinc
>    meter:  without the attenuators now in place,
>    signals generated on one phase of one service
>    panel could be detected by devices on both phases
>    of both service panels.  This was the case even
>    with a PZZ01 installed in each panel.
>
>    But with the 6285 installed, I could not operate
>    devices or meter anything on the other panel from
>    the one the CM15A was plugged into.  We tested
>    both panels that way, and they do appear to be
>    isolated from each other.
>
>5)  My method of measuring noise levels:  using
>    Mode 4 of the TesterLinc ("120kHz Activity"), I
>    can see Quality Counts of around 50, or 80, or 120
>    at various noisy times.  This usually does not
>    change as I switch branch breakers off.  The one
>    time I saw the Quality Count drop when I switched
>    off a branch circuit, I checked everything
>    plugged into the branch.  That's how I found the
>    noisy PC monitor the other night.
>
>    I plug the meter into an outlet with no other
>    resistors (appliances, x10 devices, etc) on that
>    branch.  Of course, when I shut that breaker, the
>    meter goes dead.  But there is nothing else on
>    that branch that would generate any signal or
>    noise.
>
>    As per my electrician's and my understanding of
>    Leviton's written instructions, the filter is
>    installed on a separate pair of 15 amp circuit
>    breakers.  So when I switch the filter "off", the
>    other branches stay on, including the TesterLinc's
>    meter, but the filter's branches (one for each
>    phase) are switched off.  During relatively quiet
>    times, the Quality Count may jump from 000 or 001
>    to the 20s, 30s or higher when I switch the filter
>    off.  That's how it's supposed to work.  But
>    during peak noisy times, switching off the
>    breakers feeding the 6285 cuts the Quality Count
>    from around 120 down to around 60.  That's
>    opposite of how it's supposed to work.
>
>    But based on feedback I'm getting from Robert
>    Green and Dave Houston, I suspect I don't have my
>    6285s installed properly.  (See below, very bottom
>    of this post.)
>
>6)  My only controller device at this time is the
>    CM15A.  When it transmits codes, I see Quality
>    Counts of around 50 - 60.  That's at the low end
>    of the Quality Count during our noisy evenings, as
>    I mentioned above (count can be from the 50s to
>    the 120s).
>
>    All of my dimmers are X10 RSW17 or companion RSW19
>    slave switches.  No other modules at this time,
>    but if this goes well I will add 2 or 3 plug-in
>    dimmers -- all for incandescent lights (no
>    fluorescents, CFLs, halogen low voltage
>    transformers, etc.)
>
>    We are at this time transceiving only House Code
>    L. We switched from House Code G within the first
>    week of our problems, before we bought the tester
>    and started serious troubleshooting.
>
>7)  Regarding using multiple HCA02-10E amplifiers in a
>    single home:  Leviton in fact specifies that if
>    there are sub-panels, an amplifier is required at
>    each one.  So I don't think that separate
>    HCA02-10Es at each of two main panels would be a
>    problem, but I'm not spending anything on them
>    until we deem them necessary.
>
>8)  This whole building has been solely residential
>    since it was built.  Not even doctors' offices
>    on the ground floor or commercial storefronts.
>
>
>
>I think that addresses the comments & questions posed so far.  But both
>Robert Green and Dave Houston mention stuff that bring me to doubt my
>filter installation:
>
>Following Leviton's instructions, the filter is installed on two poles
>of a 15 amp breakers:
>
>  ----------------------------------------------------
>  |                                                  |
>  |         |               |                     |  |
>  |       L1|             L2|                     |N |
>  |         |               |                     |  |
>  |   -------------   -------------               |  |
>  |   |           |   |           |               |  |
>  |   | BREAKER A |   | BREAKER B |               |  |
>  |   |    (1)    |   |    (2)    |               |  |
>  |   -------------   -------------               |  |
>  |   |           |   |           |-----|    |----|  |
>  |   | BREAKER B |   | BREAKER A |    --------   |  |
>  |   |    (3)    |   |    (4)    |    |      |   |  |
>  |   -------------   -------------    | 6285 |   |  |
>  |   |           |   |           |    |      |   |  |
>  |   | BREAKER A |   | BREAKER B |    --------   |  |
>  |   |    (5)    |   |    (6)    |-----|    |----|  |
>  |   -------------   -------------               |  |
>  |   |           |   |           |               |  |
>  |   | BREAKER B |   | BREAKER A |               |  |
>  |   |    (7)    |   |    (8)    |               |  |
>  |   -------------   -------------               |  |
>  |   |   (etc.)  |   |   (etc.)  |               |  |
>  \/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/
>
>This is how mine are installed.  At first I couldn't see how this would
>filter *all* incoming noise, i.e., the branch circuits on breakers 4
>and 6 are filtered, but wouldn't the noise bypass the filter on the
>other branch circuits?  (I mentioned earlier I'm an audio visual
>engineer.  If we apply a bandwidth filter or echo canceler to a channel
>of a mixing board, the other channels remain unfiltered.  To filter the
>whole board we would need to filter its line input or mixed output.)
>
>But I'm assuming the instructions are correct and the 6285 functions as
>a big "signal sucker" in close proximity to the other branches.  In
>addition, the instructions specify that the filter be wired to a 15 amp
>double-pole breaker (or two single pole breakers) to meet NEC spec.
>Doesn't that mean it must be on its own branch circuits?
>
>And wouldn't this mean that if there is noise generated on one of my
>branches internally (like my old PC monitor), the 6285 would suck it
>up?
>
>But Robert points out that if I shut off the filter, "all circuits it
>was filtering should be dead."  And Dave points out that "the 6285 only
>blocks signal or noise from passing in or out of your apartment's
>wiring."
>
>This suggests that the 6285 should be installed prior to the branch
>circuits, not in parallel with them.  But that would require something
>far greater than a 15 amp breaker.
>
>
>Does anyone have experience with this filter and can advise me on its
>correct installation?  Or do I have it installed correctly?  If it's
>installed correctly, why would my "noise level", defined as a Quality
>Count on a TesterLinc, sometimes double when breakers 4 & 6 (in the
>above illustration) are switched off, and at all other times be reduced
>to almost zero when the same breakers are switched off?
>
>
>
>Thanks again, and regards to all.
>
>
>-- Alan T. in NYC