I have a bunch of Eglo Giron light fittings.
These use a 22W circular T5c fluorescent lamps.

For complicated reasons I now have 6 units with no ballasts.

All the other units, with the original electronic ballast, light instantly on switch-on (but don't like the cold, below 17c they can be reluctant to light).

I've tried replacement electronic ballasts (manufacturer's spec includes T5C) from Tridonic and b,a,g - and get the same behaviour from both - they will always light regardless of temperature, but after a second or so's pause from switch-on.

Of course I want the best of both worlds - instant-on regardless of temperature.

Is there an underlying issue here with how ballasts work? Is this something to do with preheat/no-preheat?

To answer my own question (after a bit of googling):

http://en.wikipedia.org/wiki/Electro..._lamp_ballasts

http://en.wikipedia.org/wiki/Fluorescent_lamp#Starting

I think it has to be preheat issues as I had a normal tube, well a double
tube like this some years ago, it was very lightweight so obviously had a
solid state ballast and it would not light in my shed in winter, it flashed
a bit and then gave up and sulked.
Brian

--
From the Bed of Brian Gaff.
The email is valid as
Blind user.
wrote in message
...
I have a bunch of Eglo Giron light fittings.
These use a 22W circular T5c fluorescent lamps.

For complicated reasons I now have 6 units with no ballasts.

All the other units, with the original electronic ballast, light instantly
on switch-on (but don't like the cold, below 17c they can be reluctant to
light).

I've tried replacement electronic ballasts (manufacturer's spec includes
T5C) from Tridonic and b,a,g - and get the same behaviour from both - they
will always light regardless of temperature, but after a second or so's
pause from switch-on.

Of course I want the best of both worlds - instant-on regardless of
temperature.

Is there an underlying issue here with how ballasts work? Is this
something to do with preheat/no-preheat?

On Thursday, November 22, 2012 2:59:30 PM UTC, wrote:

I have a bunch of Eglo Giron light fittings.
These use a 22W circular T5c fluorescent lamps.
For complicated reasons I now have 6 units with no ballasts.
All the other units, with the original electronic ballast, light instantly on switch-on (but don't like the cold, below 17c they can be reluctant to light).
I've tried replacement electronic ballasts (manufacturer's spec includes T5C) from Tridonic and b,a,g - and get the same behaviour from both - they will always light regardless of temperature, but after a second or so's pause from switch-on.
Of course I want the best of both worlds - instant-on regardless of temperature.
Is there an underlying issue here with how ballasts work? Is this something to do with preheat/no-preheat?

Instant-on is very hard on tubes, and is best avoided

20w CFL ballasts may do the job.


NT

In article ,
" writes:
I have a bunch of Eglo Giron light fittings.
These use a 22W circular T5c fluorescent lamps.

For complicated reasons I now have 6 units with no ballasts.

All the other units, with the original electronic ballast, light instantly on switch-on (but don't like the cold, below 17c they can be reluctant to light).

I've tried replacement electronic ballasts (manufacturer's spec includes T5C) from Tridonic and b,a,g - and get the same behaviour from both - they will always light regardless of temperature, but after a second or so's pause from switch-on.

Of course I want the best of both worlds - instant-on regardless of temperature.

Is there an underlying issue here with how ballasts work? Is this something to do with preheat/no-preheat?

It has become impossible to find instant start electronic ballasts over
the last few years. The nearest you will find is the Philips Matchbox
Blue series - blue 124 LH model should be right for that tube.
RS parts 397-0277 and 397-0261 (they're just different shapes of the
same thing). They can also be found on ebay sometimes (and there are
also versions of the above two available without any case - just the PCB).

When the Blue series originally came out, it was truely instant start.
Now it has a very short pre-heat. (The red series is the proper preheat
version.)

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

In article , Andrew Gabriel
writes

It has become impossible to find instant start electronic ballasts over
the last few years. The nearest you will find is the Philips Matchbox
Blue series - blue 124 LH model should be right for that tube.
RS parts 397-0277 and 397-0261 (they're just different shapes of the
same thing). They can also be found on ebay sometimes (and there are
also versions of the above two available without any case - just the PCB).

They're showing discontinued at RS I'm afraid, don't know about
elsewhere, they look good and reasonably priced. The suggested
replacements appear to be from BCC and there's no mention of ignition
time in their data (0.1s on the ones you mentioned).

When the Blue series originally came out, it was truely instant start.
Now it has a very short pre-heat. (The red series is the proper preheat
version.)

--
fred
it's a ba-na-na . . . .

Thanks for everyone's feedback here.

I think it's best, in my application, to go for programmed-start rather than instant-start ballasts.

I bought a b,a,g, electronic ballast for £6 to evaluate, and that seems to be the better choice for tube life and cold starting.
Instant-start looks nice, but isn't handling colder conditions, and I had another early tube failure last night.
So I've approached the supplier for a price on 25 of these b,a,g, prog-start ballast units.

Incidentally, I've also looked at dimmable ballasts. Too expensive right now, but on future projects I would look at making provision in the wiring for them.