Tube or ballast on its way out?
 

Hi

I fitted a flourescent light fitting just over a year ago in the kitchen,
which worked fine, but has recently begun to start off fairly dim, before
brightening up over the course of a few minutes, although to nowhere near as
bright as it used to be.

It's got a circular 60w tube (360w equivalent apparently - it was very
bright when I fitted it) which costs about 12GBP to replace. Before I get a
new one, can anyone tell me whether these symptoms sound like it's the tube
or the electronic ballast that's dying?

Cheers

Jason

Tube or ballast on its way out?
 

In article ,
"JR" writes:
Hi

I fitted a flourescent light fitting just over a year ago in the kitchen,
which worked fine, but has recently begun to start off fairly dim, before
brightening up over the course of a few minutes, although to nowhere near as
bright as it used to be.

It's got a circular 60w tube (360w equivalent apparently - it was very
bright when I fitted it) which costs about 12GBP to replace. Before I get a
new one, can anyone tell me whether these symptoms sound like it's the tube
or the electronic ballast that's dying?

That's a difficult call -- both can fail with the symptoms
you describe. I wouldn't expect the tube to fail in a year
unless it's been on all the time or switched on and off quite
frequently. It might have been a poor tube in the first
place though. If the tube is going pink together with going
dim, then that is failure of the tube (didn't have enough
mercury in it). If either tube end has gone black, then
that would sway things slightly more towards tube failure
too, but not 100%.

You might as well try a replacement tube. A replacement
electronic ballast for a T9 tube will be significantly
harder to find (probably cheaper to buy a new fitting).
How much did the fitting cost? If it's only a bit more
than a new tube, you might as well buy a whole new fitting.
You can then swap parts to see which part is dead, if
you are interested in reusing any parts.

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

Tube or ballast on its way out?
 

In message , JR
writes
I fitted a flourescent light fitting just over a year ago in the
kitchen, which worked fine, but has recently begun to start off fairly
dim, before brightening up over the course of a few minutes, although
to nowhere near as bright as it used to be.

It's got a circular 60w tube (360w equivalent apparently - it was very
bright when I fitted it) which costs about 12GBP to replace. Before I
get a new one, can anyone tell me whether these symptoms sound like
it's the tube or the electronic ballast that's dying?

Sounds like the mercury vapour has been depleted, perhaps by being
absorbed into the phosphor or into the amalgam that may have been used
to dose the tube in the first place. Does the tube light up a dull pink
when initially turned on? If it does then it's probably the lamp.

The slow brightening is down to the mercury vapour gradually releasing
back into the lamp as it warms up.

--
Clive Mitchell
http://www.bigclive.com

Tube or ballast on its way out?
 

On 29 Apr, 20:23, "JR" wrote:

Hi

I fitted a flourescent light fitting just over a year ago in the kitchen,
which worked fine, but has recently begun to start off fairly dim, before
brightening up over the course of a few minutes, although to nowhere near as
bright as it used to be.

It's got a circular 60w tube (360w equivalent apparently - it was very
bright when I fitted it) which costs about 12GBP to replace. Before I get a
new one, can anyone tell me whether these symptoms sound like it's the tube
or the electronic ballast that's dying?

Cheers

Jason

More likely to be the tube. Trying a new tube is the only way to
know.


NT

Tube or ballast on its way out? - THANKS!
 

Just a note to say thank you to everyone who answered my question.

A new tube it is then!

Cheers

Jason