Re: Bathroom project - Cbus style lighting system....1 room only though!!

["Tim Hawes" <timsyahoo@xxxxxxxxxxxxxx>]

Noel,

I'm sure a CBus solution would give great flexibility but you're
paying a lot of "overhead" if you only do one room.
I reckon you can do DIY the "dim night light on a sensor" thing
for
around =A3100 =96 it won't be based on any fancy automation though. It
also assumes that the lamps/transformers you already have are suitable
for dimming.
(it's based on a scheme I've been thinking about for my bathroom, but
I don't want the PIR bit)

You'd run two parallel circuits from the existing ceiling rose to the
light(s) you want to come on dimmed. One circuit is as now =96 just the
switch. The second circuit contains a time-clock (get an electronic
one so it doesn't drift in power cuts), a PIR (some "nice"
ceiling-mount ones around =A330-=A340) and a conventional dimmer switch
(conventional as in one you'd fit to a wall box but suitable for
dimming the type of lights you have).

Your existing switch works at all times so if you get up early to
catch a plane etc you can still put the lights on full with the cord.
The second circuit only works between the on/off times you set (e.g.
midnight to 5am). When the time clock is off the PIR output doesn't go
anywhere, when the time-clock is on the PIR switches on the lights
through the dimmer switch which you've manually set to get the right
light level.

The only potential problem is that I've found PIRs always come on when
power is first applied, then go off. So having it after the time-clock
means the light would always come on at midnight (or whatever) when
the clock circuit is activated. I couldn't see how keeping it powered
24/7 would only activate the light between set times.

The time-clock and dimmer could go in the loft, or perhaps in the
airing cupboard to make adjustments that bit simpler. You'd probably
want to fit a master isolation switch in front of all the smarts too =96
just to make sure the auto side of the circuit doesn't unexpectedly
become live if the clock gets out of sync. Fixed wiring time-clocks
are also available so you don't have to wire-in a separate 13A socket
for a plug-in jobby.

I think that all makes sense, I don't *think* I missed anything
obvious, but you never know :-)

If you're feeling *really* adventurous you could drop the ceiling by
6", run rope light around the edge and have the rope light come on via
the timer/sensor during the night. Or rope light under the sink and/or
bath.
Or perhaps just connect one of the 6 downlighters to the auto/timer
circuit and do away with the dimmer altogether.

I shall now don my flameproof suit and ignore the cries of heretic!!

HTH,

Tim.


On Sun, Sep 28, 2008 at 12:23 PM, noel_pilot <HA@xxxxxxx> wrote:
> Hi all,
>
> I remember reading way back about someone who had a lighting setup
> whereby they have occupancy detection so lights come on automatically
> but with intelligence, i.e. if its 0200 only turn the landing/bathroom
> lights on to 15% or so so as not to blind you in your sleepy state!!
>
> I love this idea and would love to be able to replicate it for this
> project.

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