Re: Hard-wired HA lighting; was Re: XTB, reliablity, etc.

[Marc_F_Hult <MFHult@xxxxxxxxxxxxxxxxxxxxx>]

On 8 Dec 2006 15:08:26 -0800, craft.brian@xxxxxxxxx wrote in message
<1165613746.198598.192620@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>:

>Marc_F_Hult wrote:
>> On Fri, 8 Dec 2006 09:16:57 -0500, "Robert Green"
<ROBERT_GREEN1963@xxxxxxxxx>
>> wrote in message  <CbKdnWAfvr2a6OTYnZ2dnUVZ_omdnZ2d@xxxxxxx>:
>
>> Four _more_ ? Have you ever calculated what all the X-10 expenditures have
>> cost you over the years. And how much you would have earned had you spent
the
>> time tinkering with it on, say, a paper route or mowing lawns instead? Or
>> better yet, pulling wire?
>
>Pulling wire. Yeah, I've been thinking about that. The ads that suggest
>x10 as a way to "add a light switch anywhere" are clearly nonsense. It
>takes far, far less time and money to pull romex and install a switch
>than it does to make x10 reliable.
>
>But for true automation applications, what wire can be pulled? My
>impression was that hardwired systems are all fantastically expensive
>and available only to dealers/installers.

Depends in part on what you mean by "hardwired systems".

It is useful to distinguish off-the-bat between hard-wired ON-OFF and
hard-wired dimming of lights.

Hard-wired ON-OFF is something that can be controlled easily from (eg) a PC
port,ADICON Ocelot or Elk M1G, or even a hybrid control (such as X-10,
INSTEON, RF _and_ hard-wired) and can be accomplished with simple mechanical
relays or contactors. Updates to the US and Canadian electrical codes in the
past decade have made it somewhat easier to pass muster with the Authority
Having Jurisdiction (AHJ) of the National Electrical Code (NEC in US).

Hard-wired light _dimming_ is a different matter. Compared to ON-OFF, dimming
with any control signal method (PLC, RF, IR, hard-wired) is more challenging
than ON_OFF owing to:

1) the incremental difficulty of meeting code and regulatory requirements
2) the greater complexity of the hardware required
3) larger bandwidth needed for control signals
4) increase in propagated noise both through air and on the powerline.

In addition, hard-wired dimming (compared to, eg X-10) ) has the added
challenges/requirements of:

5) the prevalence of proprietary hard-wired systems (DMX512 is a notable
exception)
6) Generally greater physical/space requirements

But there are several hard-wired dimming lighting systems that are available
to  DIY folks.

... Marc
Marc_F_Hult
www.ECOntrol.org