On Thu, 2 Mar 2017 15:04:00 -0800 (PST), wrote:

On Thursday, 2 March 2017 22:46:07 UTC, Scott wrote:
On Thu, 2 Mar 2017 16:47:19 +0000, Andy Burns
wrote:

I was querying why you thought a non qualified person could remove one
type of ballast, but not the other?

If I implied that, it was wholly unintentional as I don't really know
the difference between the two.

They're very different animals. It's easy to make LEDs run on an iron ballast, but not so easy to make LEDs run on either type.

Philips seem to have achieved this?
http://www.lighting.philips.co.uk/pr...-instantfit-hf

On 03/03/2017 07:11, The Natural Philosopher wrote:

http://cdn.wellnessarticles.net/2016...75db706790.jpg

I hadn't thought about how they worked.

I had thought the starter built up then dropped the current through the
inductor so as to create a voltage spike, like a Ruhmkorff Coil. But it
also allows the filaments to heat up electrically for a short time? How
clever!

On Friday, 3 March 2017 09:08:47 UTC, Scott wrote:
On Thu, 2 Mar 2017 15:04:00 -0800 (PST), tabbypurr wrote:
On Thursday, 2 March 2017 22:46:07 UTC, Scott wrote:
On Thu, 2 Mar 2017 16:47:19 +0000, Andy Burns
wrote:

I was querying why you thought a non qualified person could remove one
type of ballast, but not the other?

If I implied that, it was wholly unintentional as I don't really know
the difference between the two.

They're very different animals. It's easy to make LEDs run on an iron ballast, but not so easy to make LEDs run on either type.

Philips seem to have achieved this?
http://www.lighting.philips.co.uk/pr...-instantfit-hf

A quick look says electronic ballasts only, not both types.
Anyway it is doable, just more complication & expense.


NT

On Fri, 3 Mar 2017 01:36:30 -0800 (PST), wrote:

On Friday, 3 March 2017 09:08:47 UTC, Scott wrote:
On Thu, 2 Mar 2017 15:04:00 -0800 (PST), tabbypurr wrote:
On Thursday, 2 March 2017 22:46:07 UTC, Scott wrote:
On Thu, 2 Mar 2017 16:47:19 +0000, Andy Burns
wrote:

I was querying why you thought a non qualified person could remove one
type of ballast, but not the other?

If I implied that, it was wholly unintentional as I don't really know
the difference between the two.

They're very different animals. It's easy to make LEDs run on an iron ballast, but not so easy to make LEDs run on either type.

Philips seem to have achieved this?
http://www.lighting.philips.co.uk/pr...-instantfit-hf

A quick look says electronic ballasts only, not both types.
Anyway it is doable, just more complication & expense.

That's because I sent the link for the HF version. There is also an
EM version. I accept it appears the same tube cannot run on either
type of ballast but it seems tubes (in the plural) can run on either
type.

'More complication and expense' - compared to what?. I suggest it
would be less complication and cheaper for someone to replace the
tubes themselves rather than employ an electrician to rewire every
lighting unit.

On Friday, 3 March 2017 09:46:44 UTC, Scott wrote:
On Fri, 3 Mar 2017 01:36:30 -0800 (PST), tabbypurr wrote:
On Friday, 3 March 2017 09:08:47 UTC, Scott wrote:
On Thu, 2 Mar 2017 15:04:00 -0800 (PST), tabbypurr wrote:
On Thursday, 2 March 2017 22:46:07 UTC, Scott wrote:
On Thu, 2 Mar 2017 16:47:19 +0000, Andy Burns
wrote:

I was querying why you thought a non qualified person could remove one
type of ballast, but not the other?

If I implied that, it was wholly unintentional as I don't really know
the difference between the two.

They're very different animals. It's easy to make LEDs run on an iron ballast, but not so easy to make LEDs run on either type.

Philips seem to have achieved this?
http://www.lighting.philips.co.uk/pr...-instantfit-hf

A quick look says electronic ballasts only, not both types.
Anyway it is doable, just more complication & expense.

That's because I sent the link for the HF version. There is also an
EM version. I accept it appears the same tube cannot run on either
type of ballast but it seems tubes (in the plural) can run on either
type.

'More complication and expense' - compared to what?. I suggest it
would be less complication and cheaper for someone to replace the
tubes themselves rather than employ an electrician to rewire every
lighting unit.

You're either trolling or complaining about a statement you haven't understood.

Fairly enlightening:

https://www.youtube.com/watch?v=43j4hrGtgGs

Huge wrote in news:eht3lhFiihjU8
@mid.individual.net:

https://www.youtube.com/watch?v=qLaD11LITbQ

Agree - but the video is about low voltage fittings.

On Fri, 3 Mar 2017 02:19:48 -0800 (PST), wrote:

On Friday, 3 March 2017 09:46:44 UTC, Scott wrote:
On Fri, 3 Mar 2017 01:36:30 -0800 (PST), tabbypurr wrote:
On Friday, 3 March 2017 09:08:47 UTC, Scott wrote:
On Thu, 2 Mar 2017 15:04:00 -0800 (PST), tabbypurr wrote:
On Thursday, 2 March 2017 22:46:07 UTC, Scott wrote:
On Thu, 2 Mar 2017 16:47:19 +0000, Andy Burns
wrote:

I was querying why you thought a non qualified person could remove one
type of ballast, but not the other?

If I implied that, it was wholly unintentional as I don't really know
the difference between the two.

They're very different animals. It's easy to make LEDs run on an iron ballast, but not so easy to make LEDs run on either type.

Philips seem to have achieved this?
http://www.lighting.philips.co.uk/pr...-instantfit-hf

A quick look says electronic ballasts only, not both types.
Anyway it is doable, just more complication & expense.

That's because I sent the link for the HF version. There is also an
EM version. I accept it appears the same tube cannot run on either
type of ballast but it seems tubes (in the plural) can run on either
type.

'More complication and expense' - compared to what?. I suggest it
would be less complication and cheaper for someone to replace the
tubes themselves rather than employ an electrician to rewire every
lighting unit.

You're either trolling or complaining about a statement you haven't understood.

Neither actually - just responding to your attempt to drive discussion
down a pedantic route.

My point was - and is - that 'retrofit' tubes are available for those
who want to swap over without rewiring the internals. It is also
possible to bypass the ballast for those who wish to do so. I thought
this information would be of practical assistance.

Your point seems to be which type of ballast is easier to remove and
the levels of technical skill needed. Probably of interest to
somebody but not to me. Remember the original question was about
replacing fluorescent lights with LED panel lights

On Friday, 3 March 2017 13:36:09 UTC, Scott wrote:
On Fri, 3 Mar 2017 02:19:48 -0800 (PST), tabbypurr wrote:
On Friday, 3 March 2017 09:46:44 UTC, Scott wrote:
On Fri, 3 Mar 2017 01:36:30 -0800 (PST), tabbypurr wrote:
On Friday, 3 March 2017 09:08:47 UTC, Scott wrote:
On Thu, 2 Mar 2017 15:04:00 -0800 (PST), tabbypurr wrote:
On Thursday, 2 March 2017 22:46:07 UTC, Scott wrote:
On Thu, 2 Mar 2017 16:47:19 +0000, Andy Burns
wrote:

I was querying why you thought a non qualified person could remove one
type of ballast, but not the other?

If I implied that, it was wholly unintentional as I don't really know
the difference between the two.

They're very different animals. It's easy to make LEDs run on an iron ballast, but not so easy to make LEDs run on either type.

Philips seem to have achieved this?
http://www.lighting.philips.co.uk/pr...-instantfit-hf

A quick look says electronic ballasts only, not both types.
Anyway it is doable, just more complication & expense.

That's because I sent the link for the HF version. There is also an
EM version. I accept it appears the same tube cannot run on either
type of ballast but it seems tubes (in the plural) can run on either
type.

'More complication and expense' - compared to what?. I suggest it
would be less complication and cheaper for someone to replace the
tubes themselves rather than employ an electrician to rewire every
lighting unit.

You're either trolling or complaining about a statement you haven't understood.

Neither actually - just responding to your attempt to drive discussion
down a pedantic route.

My point was - and is - that 'retrofit' tubes are available for those
who want to swap over without rewiring the internals. It is also
possible to bypass the ballast for those who wish to do so. I thought
this information would be of practical assistance.

Your point seems to be which type of ballast is easier to remove and
the levels of technical skill needed. Probably of interest to
somebody but not to me. Remember the original question was about
replacing fluorescent lights with LED panel lights

My point had nothing to do with that whatsoever. I won't be continuing this discussion.


NT

On Fri, 3 Mar 2017 16:21:01 -0800 (PST), wrote:

On Friday, 3 March 2017 13:36:09 UTC, Scott wrote:
On Fri, 3 Mar 2017 02:19:48 -0800 (PST), tabbypurr wrote:
On Friday, 3 March 2017 09:46:44 UTC, Scott wrote:
On Fri, 3 Mar 2017 01:36:30 -0800 (PST), tabbypurr wrote:
On Friday, 3 March 2017 09:08:47 UTC, Scott wrote:
On Thu, 2 Mar 2017 15:04:00 -0800 (PST), tabbypurr wrote:
On Thursday, 2 March 2017 22:46:07 UTC, Scott wrote:
On Thu, 2 Mar 2017 16:47:19 +0000, Andy Burns
wrote:

I was querying why you thought a non qualified person could remove one
type of ballast, but not the other?

If I implied that, it was wholly unintentional as I don't really know
the difference between the two.

They're very different animals. It's easy to make LEDs run on an iron ballast, but not so easy to make LEDs run on either type.

Philips seem to have achieved this?
http://www.lighting.philips.co.uk/pr...-instantfit-hf

A quick look says electronic ballasts only, not both types.
Anyway it is doable, just more complication & expense.

That's because I sent the link for the HF version. There is also an
EM version. I accept it appears the same tube cannot run on either
type of ballast but it seems tubes (in the plural) can run on either
type.

'More complication and expense' - compared to what?. I suggest it
would be less complication and cheaper for someone to replace the
tubes themselves rather than employ an electrician to rewire every
lighting unit.

You're either trolling or complaining about a statement you haven't understood.

Neither actually - just responding to your attempt to drive discussion
down a pedantic route.

My point was - and is - that 'retrofit' tubes are available for those
who want to swap over without rewiring the internals. It is also
possible to bypass the ballast for those who wish to do so. I thought
this information would be of practical assistance.

Your point seems to be which type of ballast is easier to remove and
the levels of technical skill needed. Probably of interest to
somebody but not to me. Remember the original question was about
replacing fluorescent lights with LED panel lights

My point had nothing to do with that whatsoever. I won't be continuing this discussion.

Good because I have no idea what your point was. You seem to have
something against 'retrofit' tubes that you are having difficulty
articulating. .

On 02/03/2017 01:04, Dave Plowman (News) wrote:
In article ,
ARW wrote:
Another advantage of the LED is that is will stay at full brightness for
it's lifespan.

Interesting. I recently replaced some 5mm white LEDs lighting a panel
meter because they'd gone dim. And they weren't driven hard either, at
about 8mA.


Did they slowly dim or suddenly dim?

--
Adam

On 05/03/17 03:05, ARW wrote:
On 02/03/2017 01:04, Dave Plowman (News) wrote:
In article ,
ARW wrote:
Another advantage of the LED is that is will stay at full brightness for
it's lifespan.

Interesting. I recently replaced some 5mm white LEDs lighting a panel
meter because they'd gone dim. And they weren't driven hard either, at
about 8mA.


Did they slowly dim or suddenly dim?

All semiconductors age. They age faster at high temperatures.

Performance generally changes gradually.

If you are interested this is MOSFET oriented, but still relevant


http://spectrum.ieee.org/semiconduct...ansistor-aging


As for LEDS..

"In conclusion, commercially available blue LEDs have
been subject to accelerated DC ageing process and their
electrical and optical characteristics are measured. It is found
that both characteristics are degraded after each ageing cycle:
the ideality factor and the reverse saturation current in I-V
characteristics increase while the peak wavelength intensity in
the electroluminescence characteristic decreases. We attribute
the degraded characteristics to the formation (or activation) of
mid-gap energy levels which can effectively function as non-
radiative recombination centres in the forward-biased mode,
and generation centres in the reverse-biased mode."

http://www.ecti-thailand.org/assets/...516_pub_25.pdf


In other words, electricity starts to be used to do other stuff than
emit light, over time.



--
"Anyone who believes that the laws of physics are mere social
conventions is invited to try transgressing those conventions from the
windows of my apartment. (I live on the twenty-first floor.) "

Alan Sokal

The Natural Philosopher wrote:

ARW wrote:

Dave Plowman wrote:

I recently replaced some 5mm white LEDs lighting a panel
meter because they'd gone dim.

Did they slowly dim or suddenly dim?

All semiconductors age. They age faster at high temperatures.

[snip]

electricity starts to be used to do other stuff than
emit light, over time.

Add to that the degradation of the phosphor(s).

In article ,
ARW wrote:
On 02/03/2017 01:04, Dave Plowman (News) wrote:
In article ,
ARW wrote:
Another advantage of the LED is that is will stay at full brightness
for it's lifespan.

Interesting. I recently replaced some 5mm white LEDs lighting a panel
meter because they'd gone dim. And they weren't driven hard either, at
about 8mA.


Did they slowly dim or suddenly dim?

Slowly. And over quite a longish period. From more than adequate for the
job to useless. The replacements from the same batch have started to do
the same. They were just generic bought from Ebay - but not the very
cheapest. First time I've seen this happen.

--
*Welcome to **** Creek - sorry, we're out of paddles*

Dave Plowman London SW
To e-mail, change noise into sound.

On 05/03/2017 18:44, Dave Plowman (News) wrote:
In article ,
ARW wrote:
On 02/03/2017 01:04, Dave Plowman (News) wrote:
In article ,
ARW wrote:
Another advantage of the LED is that is will stay at full brightness
for it's lifespan.

Interesting. I recently replaced some 5mm white LEDs lighting a panel
meter because they'd gone dim. And they weren't driven hard either, at
about 8mA.


Did they slowly dim or suddenly dim?

Slowly. And over quite a longish period. From more than adequate for the
job to useless. The replacements from the same batch have started to do
the same. They were just generic bought from Ebay - but not the very
cheapest. First time I've seen this happen.


I suppose time will tell on the ones I have fitted.

An awful lot of them were supplied for us to fit (we quoted a price for
installation only). That's a lot of hospitals and schools.

--
Adam