Re: UPB

[nobody@xxxxxxxxxxxx (Dave Houston)]

"Mark Thomas" <mrt@xxxxxxxxxxxxxx> wrote:

>I also wonder how they perform in a noisy environment (though I have
>the same question about wireless technologies). I'm not sure how to
>test that--how can I generate the right kind of noise on the line?

I'm not sure but motors, triacs and fluorescent ballasts (when turned off)
tend to put the same type of short duration, high voltage pulses on the
line. I've posted an o-scope screenshot showing triac pulses at
www.mbx-usa.com/noise.htm (scroll to the bottom of the page).

Equipment sold in Europe has to withstand these types of transients and
surges so there are standard procedures and equipment for testing. Search on
IEC 61000-4-4 and IEC 61000-4-5.

I have a fluorescent fixture in one bathroom that would, when turned off,
frequently cause an X-10 screw-in lamp module (the older, dimmable model) to
turn off. I put that lamp on an LM14A which isn't bothered by the
fluorescent but will frequently turn off when I turn an older, cheapo box
fan off (a four position rotary switch that rotates from low to medium to
high to off). The fan is on the same outlet. When it was used in another
room, it did not bother the LM14A. My Melita coffee grinder frequently tries
to start when the refrigerator compressor turns off. It did start and
complete a grind cycle when lightning hit the neighbor's tree last summer.

Here's a link to an inexpensive DIY "capacitor discharge firing box".

     http://users.dslextreme.com/~wolfstone/Pyro/cdfba_FiringBoxA.html

which might be useful to test the UPB devices.

I can understand the appeal of UPB to installers. The margins are higher and
there's a promise that there will be far fewer problems to deal with. My
concern is that there may be problems that are very difficult to diagnose
and fix.

I would not worry much about noise problems with wireless as that's fairly
easily dealt with at the design level. I think the key to its success will
be range. If you need a rather dense population of devices to insure
coverage, the total cost increases geometrically with the size of the area
that you need to cover.

I'm of the opinion that costs for doing this using something like HomePlug
and IP multicasting are rapidly falling and that it won't be long before
someone marries a triac to a BPL modem. BPL modems for ethernet over the
powerlines are now retailing for $20 or so. I thought the Control4 "Ethernet
Dimmer" might be the first one but it turns out it needs CAT5 for its
network connection.