I've got 4 kitchen lights which i would like to fit energy seving
lightbulbs to. A 2D lightbulb would probably be best but do they need
a seperate ballast?

Also does anyone know what size they are? I've gos a space 18cm square
max.

http://www.screwfix.com/prods/15094/...p-2-Pin-2D-16W

Is the type I mean

And any ideas where I would get a fitting for it

In article ,
405 TD Estate writes:
http://www.screwfix.com/prods/15094/...p-2-Pin-2D-16W

Is the type I mean

Yes, it does need a ballast.

There are two types of 2D lamp -- 2-pin and 4-pin.
The 2-pin ones have a built-in fluorescent lamp
starter and can only run from a series ballast.
The 4-pin ones have no starter and can run from
either electronic control gear (most commonly)
or you can run with same ballast as for 2-pin
types with the addition of a separate starter.

There are also 21W ones which are same physical
size as 16W, but a bit harder to find.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

In article ,
405 TD Estate writes:
And any ideas where I would get a fitting for it

Do you mean a lampholder? I buy them from RS.
170-991 is the 4-pin one I use for 10W, 16W, and 21W 2D lamps.
You have to mount it in a special shaped hole cut into a sheet
of metal (or on one occasion, I cut the mounting hole in the
casing of the electronic ballast). RS also do the 21W 2D lamps.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Which solution would be more compact? i think I will struggle to fit
the balast in.

Could one ballast be used for 4 lights? Or is the output voltage too
high so would be dangerous? Maybe then I could hide the ballast
somewhere not in the lights.

I am trying to fit the light in a box 18cm x 18 x 4 cm

I guess the 2 pin fluorescent compact lightbulbs require a ballast as
well?

On Fri, 25 Jan 2008 12:53:36 -0800 (PST) someone who may be 405 TD
Estate wrote this:-

I am trying to fit the light in a box 18cm x 18 x 4 cm

The first result from
http://www.google.co.uk/search?hl=en&q=2d+lamp+dimensions&btnG=Search&meta =cr%3DcountryUK%7CcountryGB
rapidly led me to
http://www.lamptech.co.uk/Compact%20Fluorescent.htm which has the
dimensions.

Retrofit kits used to be sold which had a bayonet fitting at one end
of a ballast box and a 2D connector at the other. One then fitted
the lamp to the ballast.

I am not clear what you are trying to fit the new lamp into and how
much space there may be above the box. However you might want to
consider something like
http://www.screwfix.com/prods/18627/Lighting/Internal-Lighting/Decorative-Wall-Ceiling/Flush-Ceiling-2D-Light-White


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

In article ,
writes:
On 26 Jan,
David Hansen wrote:

Retrofit kits used to be sold which had a bayonet fitting at one end
of a ballast box and a 2D connector at the other. One then fitted
the lamp to the ballast.

I haven't seen those for years, but the ones (sample of 3) I had proved to be
unreliable, being outlasted by the lamps.

They were supposed to have a life of about 4 lamps.
IME, it was nearer 2 lamps, but I didn't measure if it
was the lamps lasting longer or the adaptors running
shorter. The last one I had died about a year ago.
AFAIK, they were only produced during the 1980's by
Thorn Lighting (inventors of the 2D lamps) under the
Mazda label which they owned at the time (except in
the US). The combination of that adaptor and the 2D
lamp was Thorn's compact fluorescent invention (much
like Philips invented the SL18).

I have a couple of 2Ds in the
kitchen with conventional ballasts which have been reliable.

I've got one 2D in kitchen and 2 in bathroom, all in
luminares which I've built or adapted to take 2D lamps.
They're about 6 years old and all still on the first lamp,
and electronic control gear (Philips matchbox ballasts,
blue instant start versions).
I subsequently discovered I mounted the bathroom 2D tubes
in the one mounting orientation which isn't permitted
(U loops downwards), but it hasn't caused a problem yet.

I picked the 2D lamps as they had a higher initial cold
light output (as a proportion of the warmed up output)
than other compact fluorescents I measured.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Sat, 26 Jan 2008 10:58:46 GMT someone who may be
wrote this:-

Retrofit kits used to be sold which had a bayonet fitting at one end
of a ballast box and a 2D connector at the other. One then fitted
the lamp to the ballast.

I haven't seen those for years, but the ones (sample of 3) I had proved to be
unreliable, being outlasted by the lamps.

My sample of 1 has not suffered the same fate. A few lamps have
failed, but the adapter continues to work.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54