Re: What can I replace this latching relay system with?

[Marc_F_Hult <MFHult@xxxxxxxxxxxxxxxxxxxxx>]

On 26 Jul 2006 13:57:14 -0700, "Steve Wechsler" <swechsler@xxxxxxxxxxx>
wrote in message  <1153947433.681787.299640@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>:

>Just purchased a house built in the early 50s. Almost all the lights
>are controlled by latching relays, with low voltage switches in the
>walls connected to the relays in the ceiling boxes with 3 conductor
>cable (there are also some relay-controlled outlets, and I haven't yet
>figured out where the relays are for those). There is a central
>transformer, connected to each switch by additional two conductor wires
>(no idea if they are daisy chained or home run, but I assume the
>former). There are also a couple of remote multi-function switches,
>which have a knob that allow you to choose one of 10 or so different
>relays to control, along with a switch that turns the remote fixture on
>or off. I assume the remote is wired directly to the remote relays
>using more 3 conductor cable. Most wiring is similar to what we used to
>call rotor cable (for wiring up TV antenna rotors), but some is simply
>three solid conductor wires twisted together.
>
>Anyway, I'd like to replace this sytem with something a bit more
>modern. Although all the relays work (one or two are starting to give
>me a little trouble), I'd like to have the ability to dim lights, and
>even better, set up some automated controls. Is there any system that
>will allow me to use the existing wiring infrastructure? The walls are
>plaster so I don't want to tear them apart.
>
>Please respond in the newsgroup.


Some thoughts:

1) There is a yahoo group dedicated to GE Low Voltage (GELV) which may be
what you have (What you describe matches what I've seen in a GE home in
Cincinnati). I believe that folks in this group track availability of
replacement parts. They may also have some tips on retrofits.
http://groups.yahoo.com/group/gelv/?yguid=61639152

2) Three wires (more or less regardless of insulation, gauge and twisted
or not ) is adequate for local up/down dimmer controls (2 SPST with common
hot). They might also prove adequate for Dallas  1-wire  protocol
http://www.maxim-ic.com/1-Wire.cfm . So the low-voltage part of your
infrastructure can be recycled, although it might involve some home brew.
Low speed, 1-way serial control RS-232/485 is also within reach and 2-way
is possible with the addition of local dc power or a parasitic mode.

3) Presumably you want to modernize from on-off relay switching to
dimmers. I'd check into Centralite www.centralite.com as a good option
that could recycle your AC wiring. www.Homeseer.com has announced that
they will be supporting Centralite in the near future.

I have some stuff on homebrew hard-wired lighting including DMX512 at
www.ECOntrol.org, but that server will be down until the weekend.

HTH ... Marc
Marc_F_Hult
www.ECOntrol.org