RE: Lights, cabling, CBus, etc.

["Dean Barrett" <dean@xxxxxxx>]

Dont worry about drilling joists, as long as you dont go silly, i.e.
drilling middle of span, drilling lots of hole close together, you will be
ok.

You dont need to use 2.5, 1.0 or 1.5 will be adequate, you'll struggle to
terminate 2.5's.

Wiring seperately to each downlight is commendable, but i dont imagine
you'll be switching each one individually, remember a C-Bus 4 way dimmer
module is =A3320 trade.

Dont go the mains Halogen route. We were installing around 4000 of these a
year, we have now switched totally to LV. There are two big problems with
mains halogen - 1 - dimming, 2 - lamp life.

1 - I am unsure of Clispals stance on mains halogen dimming, but you will
find a number of manufacturers will no longer warrant dimmers controlling
Mains halogen, i.e. Varilight. The problem seems to be that for every 50w
o=
f
halogen you have to allow 100w of load for dimming. This can be a major
problem with standard dimmers of 250 & 400
2. Manufacturers will not warrant the life of a mains lamp, they recommend
2000 hrs, but unlike LV they do not guarantee it. At one point we were
suffering an failure rate of around 30% on branded lamps, i.e. GE, Osram,
Philips etc.

LV is much better now, 5year warrantied transformers, self diagnosising,
overheat protection. Lamps with guaranteed 5000hr life.

Yep, Clispal are developing RF, did people know they also offer Scene
Maste=
r
retrofit, that fits straight over an existing switch, and offers scene
dimming for upto three channels.

Enjoy your refit, I should be at the show with my C-Bus demo board, so come
have a play



Dean.
-----Original Message-----
From: davidsussmanuk [mailto:lists@xxxxxxx]
Sent: 07 April 2003 11:02
To: ukha_d@xxxxxxx
Subject: [ukha_d] Lights, cabling, CBus, etc.


After a long, long delay I'm finally ready to start cabling for the
new lighting. Knowing diddly squat about this (although I have been
on the cbus course), I wanted to ask a few questions. Background
first though. It's a retrofit CBus install, in the house I'm living
in so I can't just strip out the old lighting circuits and replace
them with cbus ones - I need to gradually change over, on a room by
room basis. Walls are all brick (all the way up to the roof), ground
floor is concrete, and 1st floor boarded.

I have two choices for the downstairs lights - chase the upstairs
walls and run the mains up and around to the N0 point in the loft,
or run them along under the boards to a central point and then up to
the loft. Neither option is great - 1 more mess & replastering (but
I'll be doing some of this anyway), and 2 mens flooring and drilling
joists. Given that I'm switching from 2 dangling lights in the
lounge to 6 halogen downlights (I'm not one for dangling lampshades,
plus you get better light) I'm worried about drilling too many holes
through joists. I want to run a single cable for each halogen, even
though I intend for this to be one circuit to start with. A cable
for each gives me the flexibility to split it into multiple circuits
at a later date. 6 cables through multiple joists is a bit worrying.

And leading on from that, what cabling should I use for the lights.
Is 2.5mm T&E suitable? Also, for the cat5, I know Clipsal recommend
their own, but are there other sources of lsoh/coloured cable to the
same spec?

For the halogens, I wanted to use mains powered, to avoid the buzz
that LV ones generate when dimmed. I presume there's no problem
about dimmming the mains ones? I'm thinking of something like the
standard halogens, such as those on p70 of the Screwfix catalog
(vol70), although I'd gladly accept advice on better ones.

As an aside, did you know that Clipsal are developing a retrofit
switch for CBus systems? RF switches and an RF control unit. Tail
end of the year if they get it working. They also have a UK alarm
system planned for the summer. Anyone know anything about this?

Thanks (and apologies for the long rambling post).

Dave