RE: Re: Halogens for thickies

["Dean Barrett" <dean@xxxxxxx>]

Marcus


Heat disipation from the lights is important, as is ensuring transformers
are not covered.

If heat builds up around the light, life will be reduced - fittings are
designed to allow flow of air around the lamp.

I would not worry about trying to find an IP65 light - unless you have no
tiles at all on the roof  - IP ratings for downlights are from the other
side - not the top !

65 refers to a high level of ingress protection. If you plan on putting one
in a shower cubicle then go for spashproof LV - no need for steamproof.

In the kitchen ceiling ensure you use single 60va transformers for each
downlight these will go through the same hole as the light and can be
easliy
recovered in the case of a failure.

We use transformers with self diagnosis LED's tell you if they're running
overload, short, or off if not working at all :)

The biggest advantage of using LV over mains halogen will be dimming
utilising traditional dimmers - a standard 250w dimmer will control 250w LV
no problem - if you are using mains halogen all rating have to be doubled,
therefore 250w dimmer will only control 2 x 50w mains halogen as loading on
dimmer is 100w per fitting... dont ask me why :)

In the mid floors of the property, i.e. kitchen or bathrooms in a 3 storey,
it is recommended that you attempt to preserve the integrity of the fire
barrier created by the plasterboard, this can be acheived in a number of
ways.

1. fit intumescent hoods - these have come down in price considerably and
are not feasible to fit through a 65mm cut out.
2. plasterboard the sides of the joists and ends - produces the desired
effect and allow airflow.

You should have no danger of electrocution if you've fitted LV lights
correctly, the important thing is to ensure that the mains side is
correctly
terminated into the transformer - use a 5a junction box if the transformer
is prewired - DO NOT use connectors and tape !!

You may have guessed from the above, i'm in the electrical trade :) - i'm
NICEIC qualifying manager for my company, so spend alot of my time reading
BS7671, especially part 601 onward which refers to special areas such as
bathrooms etc.


Dean.
C-Bus authorised integrator.
www.technologyintegrated.co.uk



-----Original Message-----
From: Marcus Warrington [mailto:marcusw@xxxxxxx]
Sent: 25 February 2003 18:49
To: ukha_d@xxxxxxx
Subject: [ukha_d] Re: Halogens for thickies


OK, so the transformer can go in the void but should not be covered
with insulation ?  What if the ceiling void is already filled with fibre
glass insulation.. ?

Also what about recessed halogens in an attic ceiling. Our ceiling has no
felt so I was going to use JabbaSqueeze blocks to insulate between the
rafters. Can I just cut out holes in this insulation for the lights to
sit in? I'm assuming that I would need to use IP65 rated (bathroom) lights
just in case the roof starts leaking ? I'd also need to mount the
transformer
somewhere accessible.. since I'd effectively have no void to put them in.

Marcus



> > What is the advantage of using low voltage halogens for
> ceiling lights
> > in a bathroom? Is there any danger of electrocution with
> them up there?
> >
> > Are they cheaper to run?
> >
> > Also, if I were looking to fit them i n a kitchen, where would
the
> > transformer need to go? I'm guessing that in the ceiling
> void is not a
> > good idea?