Both tubes in a flourescent are flickering and won't light. Reading up
on the symptoms suggests the ballast at fault but there's two of them so
unlikely they've both failed?

As the only thing in there that there's only one of is a capacitor, is
it likely to be that at fault?

R D S wrote:
Both tubes in a flourescent are flickering and won't light. Reading up
on the symptoms suggests the ballast at fault but there's two of them
so unlikely they've both failed?

As the only thing in there that there's only one of is a capacitor, is
it likely to be that at fault?

Is there a starter? - 35p each, I'd try this first

On 20/05/17 16:44, Phil L wrote:

Is there a starter? - 35p each, I'd try this first


Thought the same, done that.

If you have any other tubes of the same type change one and see what
happens. I'm assuming these are the standard starter type old school
fittings, like the old Thorne ones for example.
I thought the capacitor was all to do with power factors and all that?
Brian

--
----- -
This newsgroup posting comes to you directly from...
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Blind user, so no pictures please!
"R D S" wrote in message
news
Both tubes in a flourescent are flickering and won't light. Reading up on
the symptoms suggests the ballast at fault but there's two of them so
unlikely they've both failed?

As the only thing in there that there's only one of is a capacitor, is it
likely to be that at fault?

Did you get the right ones though.
Are the ends of the tubes going black? You might just be unlucky and have a
couple of failed heaters or two that are just past their best.
Brian

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This newsgroup posting comes to you directly from...
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"R D S" wrote in message
news
On 20/05/17 16:44, Phil L wrote:

Is there a starter? - 35p each, I'd try this first


Thought the same, done that.

As an aside I can remember many years ago somebody fitting a double tube
fitting in a cold store room instead of the grotty old filament bulbs that
were there.
No they never did work, flickered all the time as they were too cold!

Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!
"R D S" wrote in message
news
On 20/05/17 16:44, Phil L wrote:

Is there a starter? - 35p each, I'd try this first


Thought the same, done that.

On Sat, 20 May 2017 16:07:33 +0100, R D S wrote:

Both tubes in a flourescent are flickering and won't light. Reading up
on the symptoms suggests the ballast at fault but there's two of them so
unlikely they've both failed?

As the only thing in there that there's only one of is a capacitor, is
it likely to be that at fault?

I had a twin fluorescent unit that flickered a bit for all of its
life. I recently fitted LED retrofit replacement tubes and I am
delighted with the result. You do need to know whether the ballast is
magnetic or electronic as there are different versions.

I seem to recall my posting creating a surprising level of controversy
in this group.for some obscure reason.

On Saturday, 20 May 2017 16:07:36 UTC+1, R D S wrote:
Both tubes in a flourescent are flickering and won't light. Reading up
on the symptoms suggests the ballast at fault but there's two of them so
unlikely they've both failed?

As the only thing in there that there's only one of is a capacitor, is
it likely to be that at fault?

Some systems have the tubes in series.

On 20/05/2017 16:07, R D S wrote:
Both tubes in a flourescent are flickering and won't light. Reading up
on the symptoms suggests the ballast at fault but there's two of them so
unlikely they've both failed?

As the only thing in there that there's only one of is a capacitor, is
it likely to be that at fault?


Remove the cap and see. It does sweet FA regarding the lights actually
ability to work. A duff one could cause problems. It's only there for
power factor corrections.

Or swap the lamps for LEDS ones and bypass the ballast and the capacitor.



--
Adam

R D S wrote

Both tubes in a flourescent are flickering and won't light. Reading up on
the symptoms suggests the ballast at fault but there's two of them so
unlikely they've both failed?

As the only thing in there that there's only one of is a capacitor, is it
likely to be that at fault?

Yes, it certainly can be. Like with everything else, they dont all last
forever.

"Brian Gaff" wrote in message
news
If you have any other tubes of the same type change one and see what
happens. I'm assuming these are the standard starter type old school
fittings, like the old Thorne ones for example.

I thought the capacitor was all to do with power factors and all that?

Sure, but if its failed, can still be the problem.

"R D S" wrote in message
news
Both tubes in a flourescent are flickering and won't light. Reading up on
the symptoms suggests the ballast at fault but there's two of them so
unlikely they've both failed?

As the only thing in there that there's only one of is a capacitor, is it
likely to be that at fault?

In article ,
"Brian Gaff" writes:
As an aside I can remember many years ago somebody fitting a double tube
fitting in a cold store room instead of the grotty old filament bulbs that
were there.
No they never did work, flickered all the time as they were too cold!

They could be made to work in freezers, but there were two problems:
they need a higher starting voltage when cold, and they will run at
wrong mercury vapour pressure and hence dim if tubes couldn't warm up
to 40C glass wall temperature.

For old magnetic ballasts, you generally needed SRS (Semi-resonant
start) ballasts as they apply twice mains voltage to start the lamp.
SRS only worked with 4', 5' and 6' tubes - 4' or 5' best for low temp.
Also, tubes were manufactured which were designed to operate at
lower temperatures, although they were difficult to find. It was more
common to fit insulating sleeves to get tubes up to temperature,
although they had a longer run-up time to full light output than
using proper low temperature tubes.

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

In article ,
harry writes:
On Saturday, 20 May 2017 16:07:36 UTC+1, R D S wrote:
Both tubes in a flourescent are flickering and won't light. Reading up
on the symptoms suggests the ballast at fault but there's two of them so
unlikely they've both failed?

As the only thing in there that there's only one of is a capacitor, is
it likely to be that at fault?

Some systems have the tubes in series.

That's quite common in dual 2' fittings, although not all work that way.
The two tubes in series type require different rated starters too.
When one tube dies, the other will stop working too.

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

On Sat, 20 May 2017 20:16:42 -0000 (UTC),
(Andrew Gabriel) wrote:

In article ,
harry writes:
On Saturday, 20 May 2017 16:07:36 UTC+1, R D S wrote:
Both tubes in a flourescent are flickering and won't light. Reading up
on the symptoms suggests the ballast at fault but there's two of them so
unlikely they've both failed?

As the only thing in there that there's only one of is a capacitor, is
it likely to be that at fault?

Some systems have the tubes in series.

That's quite common in dual 2' fittings, although not all work that way.
The two tubes in series type require different rated starters too.
When one tube dies, the other will stop working too.

Quite - this is the concept of series :-)

On Saturday, 20 May 2017 16:54:53 UTC+1, R D S wrote:
On 20/05/17 16:44, Phil L wrote:

Is there a starter? - 35p each, I'd try this first


Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters, bad tubes or bad contacts. The capacitor can't cause this. Swapping over to LED won't gain a lot. If it's a series fitting, one fault somewhere will cause both to misbehave. 2' is likely to be series, 5' isn't. Series fittings require 110 starters. For any fitting the starter must cover the wattage of the lamp, so no use using a 80-105W starter on a 20W lamp.


NT

wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

Swapping over to LED won't gain a lot. If it's a series fitting, one fault
somewhere will cause both to misbehave. 2' is likely to be series, 5'
isn't.
Series fittings require 110 starters. For any fitting the starter must
cover the
wattage of the lamp, so no use using a 80-105W starter on a 20W lamp.

On 20/05/2017 22:56, Rod Speed wrote:
wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

The capacitor will be across mains in.

Can you explain, assuming the supply impedance is in the order of a
fraction of an ohm, why a capacitor can cause the perturbations in
voltage supply to cause a substantial flicker?

On Saturday, 20 May 2017 23:05:18 UTC+1, Fredxxx wrote:
On 20/05/2017 22:56, Rod Speed wrote:
tabbypurr wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

The capacitor will be across mains in.

Can you explain, assuming the supply impedance is in the order of a
fraction of an ohm, why a capacitor can cause the perturbations in
voltage supply to cause a substantial flicker?

why bother asking, it's Rod.


NT

Fredxxx wrote
Rod Speed wrote
wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

And is in fact by far the most likely problem when the tubes
arent connected in series after the things he has tried already.

The capacitor will be across mains in.

Yes.

Can you explain, assuming the supply impedance is in the
order of a fraction of an ohm, why a capacitor can cause the
perturbations in voltage supply to cause a substantial flicker?

You havent established that it is causing perturbations
in the voltage supply. And it can obviously do that by
not being a viable cap anymore anyway.

wrote in message
...
On Saturday, 20 May 2017 23:05:18 UTC+1, Fredxxx wrote:
On 20/05/2017 22:56, Rod Speed wrote:
tabbypurr wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

The capacitor will be across mains in.

Can you explain, assuming the supply impedance is in the order of a
fraction of an ohm, why a capacitor can cause the perturbations in
voltage supply to cause a substantial flicker?

why bother asking, it's Rod.

You never could bull**** your way out of a wet paper bag.

On Saturday, 20 May 2017 23:14:13 UTC+1, Rod Speed wrote:
Fredxxx wrote
Rod Speed wrote
tabbypurr wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

And is in fact by far the most likely problem when the tubes
arent connected in series after the things he has tried already.

The capacitor will be across mains in.

Yes.

Can you explain, assuming the supply impedance is in the
order of a fraction of an ohm, why a capacitor can cause the
perturbations in voltage supply to cause a substantial flicker?

You havent established that it is causing perturbations
in the voltage supply. And it can obviously do that by
not being a viable cap anymore anyway.

Give the man a verbal diarrhoea pill.

On 20/05/2017 23:17, Rod Speed wrote:


wrote in message
...
On Saturday, 20 May 2017 23:05:18 UTC+1, Fredxxx wrote:
On 20/05/2017 22:56, Rod Speed wrote:
tabbypurr wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

The capacitor will be across mains in.

Can you explain, assuming the supply impedance is in the order of a
fraction of an ohm, why a capacitor can cause the perturbations in
voltage supply to cause a substantial flicker?

why bother asking, it's Rod.

You never could bull**** your way out of a wet paper bag.

You normally resort to this form of abuse when proved wrong.

On 20/05/2017 23:14, Rod Speed wrote:
Fredxxx wrote
Rod Speed wrote
wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

And is in fact by far the most likely problem when the tubes
arent connected in series after the things he has tried already.
The capacitor will be across mains in.

Yes.

Good, we have got that far.

Can you explain, assuming the supply impedance is in the order of a
fraction of an ohm, why a capacitor can cause the perturbations in
voltage supply to cause a substantial flicker?

You havent established that it is causing perturbations in the voltage
supply. And it can obviously do that by not being a viable cap anymore
anyway.

Is that an admission that its not the capacitor?

Or are you thinking of some other capacitor characteristic that might
cause this flicker, if so do tell.

wrote in message
...
On Saturday, 20 May 2017 23:14:13 UTC+1, Rod Speed wrote:
Fredxxx wrote
Rod Speed wrote
tabbypurr wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

And is in fact by far the most likely problem when the tubes
arent connected in series after the things he has tried already.

The capacitor will be across mains in.

Yes.

Can you explain, assuming the supply impedance is in the
order of a fraction of an ohm, why a capacitor can cause the
perturbations in voltage supply to cause a substantial flicker?

You havent established that it is causing perturbations
in the voltage supply. And it can obviously do that by
not being a viable cap anymore anyway.

Give the man a verbal diarrhoea pill.

You never could bull**** your way out of a wet paper bag.

"Fredxxx" wrote in message
news
On 20/05/2017 23:17, Rod Speed wrote:


wrote in message
...
On Saturday, 20 May 2017 23:05:18 UTC+1, Fredxxx wrote:
On 20/05/2017 22:56, Rod Speed wrote:
tabbypurr wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

The capacitor will be across mains in.

Can you explain, assuming the supply impedance is in the order of a
fraction of an ohm, why a capacitor can cause the perturbations in
voltage supply to cause a substantial flicker?

why bother asking, it's Rod.

You never could bull**** your way out of a wet paper bag.

You normally resort to this form of abuse when proved wrong.

Havent been proven wrong, ****wit.

"Fredxxx" wrote in message
news
On 20/05/2017 23:14, Rod Speed wrote:
Fredxxx wrote
Rod Speed wrote
wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

And is in fact by far the most likely problem when the tubes
arent connected in series after the things he has tried already.
The capacitor will be across mains in.

Yes.

Good, we have got that far.

Can you explain, assuming the supply impedance is in the order of a
fraction of an ohm, why a capacitor can cause the perturbations in
voltage supply to cause a substantial flicker?

You havent established that it is causing perturbations in the voltage
supply. And it can obviously do that by not being a viable cap anymore
anyway.

Is that an admission that its not the capacitor?

Nope. If the tubes arent in series, that is by far
the most likely cause of the problem given
what he has tried that has made no difference.

Or are you thinking of some other capacitor characteristic that might
cause this flicker,

Failure mode of electros, yep.

if so do tell.

Most obviously if its got a significant partial short
now, as electros sometimes do when they have failed.
That could easily see the tubes no longer getting full
mains voltage anymore, and so flicker now.

On 21/05/2017 00:07, Rod Speed wrote:


"Fredxxx" wrote in message
news
On 20/05/2017 23:14, Rod Speed wrote:
Fredxxx wrote
Rod Speed wrote
wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

And is in fact by far the most likely problem when the tubes
arent connected in series after the things he has tried already.
The capacitor will be across mains in.

Yes.

Good, we have got that far.

Can you explain, assuming the supply impedance is in the order of a
fraction of an ohm, why a capacitor can cause the perturbations in
voltage supply to cause a substantial flicker?

You havent established that it is causing perturbations in the voltage
supply. And it can obviously do that by not being a viable cap anymore
anyway.

Is that an admission that its not the capacitor?

Nope. If the tubes arent in series, that is by far
the most likely cause of the problem given
what he has tried that has made no difference.

Or are you thinking of some other capacitor characteristic that might
cause this flicker,

Failure mode of electros, yep.

Electros? Is this a new component technology?

Certainly electrolytic capacitors are rarely used across AC mains, so it
must be some other capacitor technology.

if so do tell.

Most obviously if its got a significant partial short
now, as electros sometimes do when they have failed.
That could easily see the tubes no longer getting full
mains voltage anymore, and so flicker now.

Are you now suggesting this partial short will be causing perturbations
on mains voltage? Previously you said we haven't established that such a
"partial short" would cause "perturbations in the voltage supply". You
really ought to make your mind up.

Fredxxx wrote
Rod Speed wrote
Fredxxx wrote
Rod Speed wrote
Fredxxx wrote
Rod Speed wrote
wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

And is in fact by far the most likely problem when the tubes
arent connected in series after the things he has tried already.
The capacitor will be across mains in.

Yes.

Good, we have got that far.

Can you explain, assuming the supply impedance is in the order of a
fraction of an ohm, why a capacitor can cause the perturbations in
voltage supply to cause a substantial flicker?

You havent established that it is causing perturbations in the voltage
supply. And it can obviously do that by not being a viable cap anymore
anyway.

Is that an admission that its not the capacitor?

Nope. If the tubes arent in series, that is by far
the most likely cause of the problem given
what he has tried that has made no difference.

Or are you thinking of some other capacitor characteristic that might
cause this flicker,

Failure mode of electros, yep.

Electros? Is this a new component technology?

Certainly electrolytic capacitors are rarely used across AC mains, so it
must be some other capacitor technology.

if so do tell.

Most obviously if its got a significant partial short
now, as electros sometimes do when they have failed.
That could easily see the tubes no longer getting full
mains voltage anymore, and so flicker now.

Are you now suggesting this partial short will be causing perturbations on
mains voltage?

Nope, reduced mains voltage across the tubes.

And I didnt say WILL BE, I said IF.

Previously you said we haven't established that such a "partial short"
would cause "perturbations in the voltage supply".

Everyone can see themselves that I said nothing of the sort previously.

You really ought to make your mind up.

You never could bull**** your way out of a wet paper bag.

And Adam has said that it could be the cap.

You'll have to pardon us who consider that he has
seen a hell of a lot more fluoros with that fault than
you ever have might just have a tad more of a ****ing
clue about whether a cap can do that than you have.

R D S wrote:
Both tubes in a flourescent are flickering and won't light. Reading up
on the symptoms suggests the ballast at fault but there's two of them so
unlikely they've both failed?

As the only thing in there that there's only one of is a capacitor, is
it likely to be that at fault?


Maybe they are making a cake?

On Sunday, 21 May 2017 05:10:50 UTC+1, Rod Speed wrote:
Fredxxx wrote
Rod Speed wrote
Fredxxx wrote
Rod Speed wrote
Fredxxx wrote
Rod Speed wrote
tabbypurr wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

And is in fact by far the most likely problem when the tubes
arent connected in series after the things he has tried already.
The capacitor will be across mains in.

Yes.

Good, we have got that far.

Can you explain, assuming the supply impedance is in the order of a
fraction of an ohm, why a capacitor can cause the perturbations in
voltage supply to cause a substantial flicker?

You havent established that it is causing perturbations in the voltage
supply. And it can obviously do that by not being a viable cap anymore
anyway.

Is that an admission that its not the capacitor?

Nope. If the tubes arent in series, that is by far
the most likely cause of the problem given
what he has tried that has made no difference.

Or are you thinking of some other capacitor characteristic that might
cause this flicker,

Failure mode of electros, yep.

Electros? Is this a new component technology?

Certainly electrolytic capacitors are rarely used across AC mains, so it
must be some other capacitor technology.

if so do tell.

Most obviously if its got a significant partial short
now, as electros sometimes do when they have failed.
That could easily see the tubes no longer getting full
mains voltage anymore, and so flicker now.

Are you now suggesting this partial short will be causing perturbations on
mains voltage?

Nope, reduced mains voltage across the tubes.

And I didnt say WILL BE, I said IF.

Previously you said we haven't established that such a "partial short"
would cause "perturbations in the voltage supply".

Everyone can see themselves that I said nothing of the sort previously.

You really ought to make your mind up.

You never could bull**** your way out of a wet paper bag.

And Adam has said that it could be the cap.

You'll have to pardon us who consider that he has
seen a hell of a lot more fluoros with that fault than
you ever have might just have a tad more of a ****ing
clue about whether a cap can do that than you have.

He's rarely this funny. Why argue with him.

Well fancy that, never knew they did all of that. Might also explain why a
cheap Woolies job that plugged into a bayonet with two 2ft tubes never
worked right when the weather was cold. I hardly think Wollies could be
bothered. Never did figure out how those worked as they were very
lightweight, no big ballast or visible starters, they sort of faded on,
except when it was cold when they faded on, went out then faded on then went
out etc!

Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!
"Andrew Gabriel" wrote in message
news
In article ,
"Brian Gaff" writes:
As an aside I can remember many years ago somebody fitting a double tube
fitting in a cold store room instead of the grotty old filament bulbs
that
were there.
No they never did work, flickered all the time as they were too cold!

They could be made to work in freezers, but there were two problems:
they need a higher starting voltage when cold, and they will run at
wrong mercury vapour pressure and hence dim if tubes couldn't warm up
to 40C glass wall temperature.

For old magnetic ballasts, you generally needed SRS (Semi-resonant
start) ballasts as they apply twice mains voltage to start the lamp.
SRS only worked with 4', 5' and 6' tubes - 4' or 5' best for low temp.
Also, tubes were manufactured which were designed to operate at
lower temperatures, although they were difficult to find. It was more
common to fit insulating sleeves to get tubes up to temperature,
although they had a longer run-up time to full light output than
using proper low temperature tubes.

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

Those series systems were a load of old rubbish not to be touched by a barge
pole. I had one of those for little tubes in a rostrum camera CCTV magnifier
which had a transistor ballast. In the end had to fit two one for each tube
due to it just not coming on sometimes.
Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!
wrote in message
...
On Saturday, 20 May 2017 16:54:53 UTC+1, R D S wrote:
On 20/05/17 16:44, Phil L wrote:

Is there a starter? - 35p each, I'd try this first


Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters, bad tubes or
bad contacts. The capacitor can't cause this. Swapping over to LED won't
gain a lot. If it's a series fitting, one fault somewhere will cause both to
misbehave. 2' is likely to be series, 5' isn't. Series fittings require 110
starters. For any fitting the starter must cover the wattage of the lamp, so
no use using a 80-105W starter on a 20W lamp.


NT

The capacitor would need to be very leaky to cause this though, and it
normally happens gradually.
Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!
"Rod Speed" wrote in message
...
wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

Swapping over to LED won't gain a lot. If it's a series fitting, one
fault
somewhere will cause both to misbehave. 2' is likely to be series, 5'
isn't.
Series fittings require 110 starters. For any fitting the starter must
cover the
wattage of the lamp, so no use using a 80-105W starter on a 20W lamp.

wrote in message
...
On Sunday, 21 May 2017 05:10:50 UTC+1, Rod Speed wrote:
Fredxxx wrote
Rod Speed wrote
Fredxxx wrote
Rod Speed wrote
Fredxxx wrote
Rod Speed wrote
tabbypurr wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

And is in fact by far the most likely problem when the tubes
arent connected in series after the things he has tried already.
The capacitor will be across mains in.

Yes.

Good, we have got that far.

Can you explain, assuming the supply impedance is in the order of a
fraction of an ohm, why a capacitor can cause the perturbations in
voltage supply to cause a substantial flicker?

You havent established that it is causing perturbations in the
voltage
supply. And it can obviously do that by not being a viable cap
anymore
anyway.

Is that an admission that its not the capacitor?

Nope. If the tubes arent in series, that is by far
the most likely cause of the problem given
what he has tried that has made no difference.

Or are you thinking of some other capacitor characteristic that might
cause this flicker,

Failure mode of electros, yep.

Electros? Is this a new component technology?

Certainly electrolytic capacitors are rarely used across AC mains, so
it
must be some other capacitor technology.

if so do tell.

Most obviously if its got a significant partial short
now, as electros sometimes do when they have failed.
That could easily see the tubes no longer getting full
mains voltage anymore, and so flicker now.

Are you now suggesting this partial short will be causing perturbations
on
mains voltage?

Nope, reduced mains voltage across the tubes.

And I didnt say WILL BE, I said IF.

Previously you said we haven't established that such a "partial short"
would cause "perturbations in the voltage supply".

Everyone can see themselves that I said nothing of the sort previously.

You really ought to make your mind up.

You never could bull**** your way out of a wet paper bag.

And Adam has said that it could be the cap.

You'll have to pardon us who consider that he has
seen a hell of a lot more fluoros with that fault than
you ever have might just have a tad more of a ****ing
clue about whether a cap can do that than you have.

He's rarely this funny. Why argue with him.

You never could bull**** your way out of a wet paper bag.

Brian Gaff wrote

The capacitor would need to be very leaky to cause this though,

Yes, you don’t see that result very often at all, but one
of the reasons for that is that they don’t all have a cap.

Its only for power factor correction and that
is only common with the industrial versions.

and it normally happens gradually.

Not as far as when it gets bad enough to be visible is concerned.

"Rod Speed" wrote in message
...
wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

Swapping over to LED won't gain a lot. If it's a series fitting, one
fault
somewhere will cause both to misbehave. 2' is likely to be series, 5'
isn't.
Series fittings require 110 starters. For any fitting the starter must
cover the
wattage of the lamp, so no use using a 80-105W starter on a 20W lamp.

On Sunday, 21 May 2017 11:24:31 UTC+1, Rod Speed wrote:
Brian Gaff wrote

The capacitor would need to be very leaky to cause this though,

Yes, you dont see that result very often at all, but one
of the reasons for that is that they dont all have a cap.

Rodiot can't get anything right today

And Adam has said that it could be the cap.

You'll have to pardon us who consider that he has
seen a hell of a lot more fluoros with that fault than
you ever have might just have a tad more of a ****ing
clue about whether a cap can do that than you have.


Ooh, Please sir, Adam said it could be the cap!

He probably said that just to lure you into a false sense of security.


--

Graham.
%Profound_observation%

wrote in message
...
On Sunday, 21 May 2017 11:24:31 UTC+1, Rod Speed wrote:
Brian Gaff wrote

The capacitor would need to be very leaky to cause this though,

Yes, you dont see that result very often at all, but one
of the reasons for that is that they dont all have a cap.

Rodiot can't get anything right today

You never could bull**** your way out of a wet paper bag.

The cap is for power factor correction. Not all fluoros have one.

"Graham." wrote in message
...


And Adam has said that it could be the cap.

You'll have to pardon us who consider that he has
seen a hell of a lot more fluoros with that fault than
you ever have might just have a tad more of a ****ing
clue about whether a cap can do that than you have.


Ooh, Please sir, Adam said it could be the cap!

Been having those pathetic little fantasys long ?

He probably said that just to lure
you into a false sense of security.

He said it because he has seen it.

And its obvious to anyone with even half a clue
that one of those caps can fail in a way that will
see a lower than normal voltage across the tubes
and that can see them flicker.

And completely trivial to see if the cap is the
problem by disconnecting it, doesn't even cost
any more than a small amount of time to try.

On 21/05/2017 05:05, Rod Speed wrote:
Fredxxx wrote
Rod Speed wrote
Fredxxx wrote
Rod Speed wrote
Fredxxx wrote
Rod Speed wrote
wrote
R D S wrote
Phil L wrote

Is there a starter? - 35p each, I'd try this first

Thought the same, done that.

So you've got switchstart fittings. Then it's wrong starters,
bad tubes or bad contacts. The capacitor can't cause this.

Corse it can.

And is in fact by far the most likely problem when the tubes
arent connected in series after the things he has tried already.
The capacitor will be across mains in.

Yes.

Good, we have got that far.

Can you explain, assuming the supply impedance is in the order of a
fraction of an ohm, why a capacitor can cause the perturbations in
voltage supply to cause a substantial flicker?

You havent established that it is causing perturbations in the voltage
supply. And it can obviously do that by not being a viable cap anymore
anyway.

Is that an admission that its not the capacitor?

Nope. If the tubes arent in series, that is by far
the most likely cause of the problem given
what he has tried that has made no difference.

Or are you thinking of some other capacitor characteristic that might
cause this flicker,

Failure mode of electros, yep.

Electros? Is this a new component technology?

Certainly electrolytic capacitors are rarely used across AC mains, so
it must be some other capacitor technology.

if so do tell.

Most obviously if its got a significant partial short
now, as electros sometimes do when they have failed.
That could easily see the tubes no longer getting full
mains voltage anymore, and so flicker now.

Are you now suggesting this partial short will be causing
perturbations on mains voltage?

Nope, reduced mains voltage across the tubes.

And I didnt say WILL BE, I said IF.

Previously you said we haven't established that such a "partial short"
would cause "perturbations in the voltage supply".

Everyone can see themselves that I said nothing of the sort previously.

You really ought to make your mind up.

You never could bull**** your way out of a wet paper bag.

Is that your answer to a question you have failed to answer?

You said it could be the cap. I have asked how:
"Can you explain, assuming the supply impedance is in the order of a
fraction of an ohm, why a capacitor can cause the perturbations in
voltage supply to cause a substantial flicker?"

You are incapable of providing an answer as to how a faulty capacitor
can cause flicker.

And Adam has said that it could be the cap.

If Adam said "jump of a cliff" would you feel obliged?