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
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.
In article ,
405 TD Estate writes:
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.
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
On Fri, 25 Jan 2008 12:53:36 -0800 (PST) someone who may be 405 TD
Estate wrote this:-
The first result from
rapidly led me to
which has the
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
On 26 Jan,
I haven't seen those for years, but the ones (sample of 3) I had proved to be
unreliable, being outlasted by the lamps. I have a couple of 2Ds in the
kitchen with conventional ballasts which have been reliable.
In article ,
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'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.