Interesting ...

[Arfa Daily]

"Rod Speed" <rod.speed.aaa@gmail.com> wrote in message
news:cgubooFnch2U1@mid.individual.net...

Some gutless fuckwit desperately cowering behind
Arfa Daily <arfa.daily@ntlworld.com> wrote just the
puerile shit that always pours from the back of it when its got done like
a fucking dinner, as it always is by everyone.

Everybody who matters knows exactly who I am. You are just not one who
*does* matter Rod. The email address is valid. I'm sure if you were clever
enough to be able to look it up, you could get me right down to a street
address. As for me writing puerile shit, the words pot, kettle and black
come to mind. Most of what you write is *total* shit that no one wants to
hear, and frequently tell you so. But you are so full of yourself and your
opinionated crap, that it all goes over your head. Much like certain other
of your countrymen, as soon as anyone dares to call you out on your mindless
pontifications, you just revert to type, and start screaming bucket-mouthed
abuse. Why don't you just do everyone a big favour, and piss off for another
six months like you often do. And where are you when you do disappear ? In
jail, with any luck ...

Arfa

- or Geoff, if you prefer

 

[Phil Allison]

John Robertson wrote:

As usual, heat is the enemy. Reading the technical specs for caps is
enlightening. They are rated usually at something like 2,000 to 5,000
hours at their rated temperature.

** Usually that number include operation at rated ripple current too.

So an 80C cap will die after something
like 2000 hrs at 80C

** I constantly see large can electros rated at 85C running operating in a 95C ambient that are 30 years old and still fine. Brand is LCR made in England, used in Marshall valve amplifiers and placed right next to the E34 output valves.

or 4000 hours at 50C and 10000 hours at 40C (not
looking it up!), whereas a 105C cap will last 10000 hours at 85C, etc.
So, the better the grade of cap the longer it will last in warm to hot
environments.

** 105C electros are pretty much industry standard these days.

Some of them last a long time and some do not.

It has more to do with ripple current and quality of manufacture than anything else.

And there is the equivalent resistance and inductance to
consider as well.

** Low ESR caps have proved to be the most unreliable of the lot - cos so many Asian makers got the chemistry wrong.

Inductance is however a non issue, electros of similar physical size and lead arrangement have the same inductance - usually not more than 25nH.


..... Phil

 

[Phil Allison]

Tim Watts wrote:

Just out of interest, do any mains LEDs use simple reactive droppers, eg
capacitor or inductor, then bridge rectifier and smoothing capacitor?

** Only possible with low power lamps - a few watts at most - beyond which the power factor gets very poor and switch-on surges unacceptable.

And do 12V LEDs have driver circuits which are less stressed than their
mains equivalents? ie are 12V formats more likely to last longer?

** Almost certainly.


..... Phil

 

[F Murtz]

Jeff Liebermann wrote:

On 3 Jan 2015 06:50:55 GMT, Bob Eager <news0005@eager.cx> wrote:

On Fri, 02 Jan 2015 17:32:41 -0800, Jeff Liebermann wrote:

All this begs the question "Why did the author write the article"? Scott
That also begs the question "Why did Arfa Daily post the article"? My
This also begs the question "Why did I write this long rant when I

http://afterdeadline.blogs.nytimes.com/2008/09/25/begging-the-question-again/?_r=0

Please put carrets around URL's so that the Usenet server doesn't
reformat it by wrapping the lines.

Please post definition of "carrets" as entering it in many ways in
google fails to find answer.

If your one-line comment is about my use of "begs the question",
you're correct that mine was not the correct usage. It should have
been "raises the question" as described in:
http://begthequestion.info
My appologies. I'll instruct my proof reader to check for such
grammatical errors.

 

[F Murtz]

Jeff Liebermann wrote:

On 3 Jan 2015 06:50:55 GMT, Bob Eager <news0005@eager.cx> wrote:

On Fri, 02 Jan 2015 17:32:41 -0800, Jeff Liebermann wrote:

All this begs the question "Why did the author write the article"? Scott
That also begs the question "Why did Arfa Daily post the article"? My
This also begs the question "Why did I write this long rant when I

http://afterdeadline.blogs.nytimes.com/2008/09/25/begging-the-question-again/?_r=0

Please put carrets around URL's so that the Usenet server doesn't
reformat it by wrapping the lines.

If your one-line comment is about my use of "begs the question",
you're correct that mine was not the correct usage. It should have
been "raises the question" as described in:
http://begthequestion.info
My appologies. I'll instruct my proof reader to check for such
grammatical errors.

Are those sideways less than more than symbols Carets? I thought that ^
is a carete and would such a caret before and after the URL work?

 

[Tim Watts]

On 06/01/15 06:10, John Robertson wrote:

As usual, heat is the enemy. Reading the technical specs for caps is
enlightening. They are rated usually at something like 2,000 to 5,000
hours at their rated temperature. So an 80C cap will die after something
like 2000 hrs at 80C or 4000 hours at 50C and 10000 hours at 40C (not
looking it up!), whereas a 105C cap will last 10000 hours at 85C, etc.
So, the better the grade of cap the longer it will last in warm to hot
environments. And there is the equivalent resistance and inductance to
consider as well. Some caps are much more tolerant of 50/60hz and others
are better at 20,000hz. Selecting those takes time and the cost
accountants slip in at some point...

That's very interesting.

Based on this random driver circuit:

http://www.ecnmag.com/sites/ecnmag.com/files/legacyimages/ECN/Articles/2010/12/Fig%206-web(1).jpg

and looking at RS for 680uF around 50V electrolytics:

the 105C are around 50-70 pence
125C are around 130 pence
150C are 252 pence

There seems to be 1 big cap in that circuit - I don't have time now to
cost all of the electrolytics but this looks like a case of adding maybe
3 pounds would make the difference between a short life and a very long
life.

I suspect Philips use the good components - their LED bulbs seem to last
a long time (my tests are still pending) but they cost rather more than
3 pounds over the cheaper LEDs.

 

[Tim Watts]

On 06/01/15 06:10, John Robertson wrote:

As usual, heat is the enemy. Reading the technical specs for caps is
enlightening. They are rated usually at something like 2,000 to 5,000
hours at their rated temperature. So an 80C cap will die after something
like 2000 hrs at 80C or 4000 hours at 50C and 10000 hours at 40C (not
looking it up!), whereas a 105C cap will last 10000 hours at 85C, etc.
So, the better the grade of cap the longer it will last in warm to hot
environments. And there is the equivalent resistance and inductance to
consider as well. Some caps are much more tolerant of 50/60hz and others
are better at 20,000hz. Selecting those takes time and the cost
accountants slip in at some point...

Just out of interest, do any mains LEDs use simple reactive droppers, eg
capacitor or inductor, then bridge rectifier and smoothing capacitor?

And do 12V LEDs have driver circuits which are less stressed than their
mains equivalents? ie are 12V formats more likely to last longer?

 

[The Natural Philosopher]

On 06/01/15 08:07, Tim Watts wrote:

On 06/01/15 06:10, John Robertson wrote:

As usual, heat is the enemy. Reading the technical specs for caps is
enlightening. They are rated usually at something like 2,000 to 5,000
hours at their rated temperature. So an 80C cap will die after something
like 2000 hrs at 80C or 4000 hours at 50C and 10000 hours at 40C (not
looking it up!), whereas a 105C cap will last 10000 hours at 85C, etc.
So, the better the grade of cap the longer it will last in warm to hot
environments. And there is the equivalent resistance and inductance to
consider as well. Some caps are much more tolerant of 50/60hz and others
are better at 20,000hz. Selecting those takes time and the cost
accountants slip in at some point...

Just out of interest, do any mains LEDs use simple reactive droppers, eg
capacitor or inductor, then bridge rectifier and smoothing capacitor?

I suspect not at this point in time.

The problem is that an inductor is large and expensive at 50hz.

Consider 25W of LED. that represents 100mA of current, or an inductor
impedance of around 2.4k ohms 7.6 henries.

That is a fairly large beast. Too large for a light bulb - and indeed
its pretty similar to what's inside a fluorescent ballast of similar
wattage.

Ergo these days we rectify, smooth and chop and transform at much higher
freqs than 50hz to get power at different voltages or to achieve current
limiting. And that gets rid of 100hz flicker too..or should,

And it gets rid of big iron cored chokes. smaller cheaper ferrites with
less copper involved are far far cheaper.

BUT you have the switching transistors and the rectification and
smoothing components operating at high power and mains voltage - bad
reliability especially when HOT.

Actually what is needed is the electronics independent of the bulb.
Maybe built into the light fitting, as it is with fluorescent. And
independently replaceable.

And do 12V LEDs have driver circuits which are less stressed than their
mains equivalents? ie are 12V formats more likely to last longer?

Probably. switching at 12V is not such a hard task for most electronics

The problems of LED bulbs are nothing to do with LEDS and a lot to do
with miniaturisation and cost.

Personally I think that we should be looking at LED lights that are
neither ES nor bayonet, but in fact sit on the end of a piece of wire,
and are large enough and expensive enough to be considered fittings, not
consumables, and simply get wired in when the house is built.

And last at least 15 years.

E.g. you replace a ceiling rose assembly with something remote from the
'bulb' that drives the 'bulb' over a piece of wire at LV. Or you have
integrated lumieres that replace conventional ones.

And indeed in-wall power supplies for designer lighting etc.


--
Everything you read in newspapers is absolutely true, except for the
rare story of which you happen to have first-hand knowledge. – Erwin Knoll

 

[john james]

"Tim Watts" <tw_usenet@dionic.net> wrote in message
news:lmhsnb-4d8.ln1@squidward.dionic.net...

On 06/01/15 06:10, John Robertson wrote:

As usual, heat is the enemy. Reading the technical specs for caps is
enlightening. They are rated usually at something like 2,000 to 5,000
hours at their rated temperature. So an 80C cap will die after something
like 2000 hrs at 80C or 4000 hours at 50C and 10000 hours at 40C (not
looking it up!), whereas a 105C cap will last 10000 hours at 85C, etc.
So, the better the grade of cap the longer it will last in warm to hot
environments. And there is the equivalent resistance and inductance to
consider as well. Some caps are much more tolerant of 50/60hz and others
are better at 20,000hz. Selecting those takes time and the cost
accountants slip in at some point...

Just out of interest, do any mains LEDs use simple reactive droppers, eg
capacitor or inductor, then bridge rectifier and smoothing capacitor?

And do 12V LEDs have driver circuits which are less stressed than their
mains equivalents? ie are 12V formats more likely to last longer?

Yes, you don’t need to use caps at all with some configurations of
those, most obviously with series leds.

 

[Tim Watts]

On 06/01/15 10:47, john james wrote:

"Tim Watts" <tw_usenet@dionic.net> wrote in message
news:lmhsnb-4d8.ln1@squidward.dionic.net...
On 06/01/15 06:10, John Robertson wrote:

And do 12V LEDs have driver circuits which are less stressed than
their mains equivalents? ie are 12V formats more likely to last longer?

Yes, you don’t need to use caps at all with some configurations of
those, most obviously with series leds.

So one thing is clear - if I decide to deploy high power LEDs I might be
better offering a SELV supply to them and choosing fittings that can
take 12V lamps.

As it happens, I will be using LEDs in a number of relatively open
fittings (GU10s ion the end of stalks, plenty of air), 3 very low power
GU10s in downlighters (2-3W range) as night lighting in the hall.

Other candidates are some 12V G4s in the bathroom, enclosed and some
GX53s (open fitting). So on the whole I should be doing OK with LED
retro fit as the price comes down.

 

[Adrian Tuddenham]

The Natural Philosopher <tnp@invalid.invalid> wrote:

[...]

Ergo these days we rectify, smooth and chop and transform at much higher
freqs than 50hz to get power at different voltages or to achieve current
limiting. And that gets rid of 100hz flicker too..or should,

The flicker will only disappear if you use a large capacitor as a
storage element; usually this is found on the HV side of the inverter.
This brings back the reliability problem: it is asking a lot of a big
capacitor to survive for many years when it is potentially exposed to
occasional mains glitches from one side and continuously exposed to the
switching current waveform on the other.

For a given energy storage capacity, capacitors are smaller, lighter and
cheaper than metal-cored chokes, but it is a lot more difficult to make
them as reliable in the long term.


--
~ Adrian Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk

 

[Bob Eager]

On Mon, 05 Jan 2015 21:31:00 -0500, Phil Hobbs wrote:

Brr. Ledu is a crappy knockoff of Luxo. I got one by mistake, and it
rapidly went into the trash. Trust me, the $200 a real Luxo costs is a
bargain in the long run.

Indeed. I got a secondhand Luxo in 1974, and it finally packed up a
couple of years ago. It was of course replaced by...a Luxo. We also have
a couple of ten year old ones on our office desks at home, one right next
to me here.

Highly recommended, if you have a couple of hundred 100W incandescents
stashed in a cupboard like mine.

And mine.

--
My posts are my copyright and if @diy_forums or Home Owners' Hub
wish to copy them they can pay me ÂŁ30a message.
Use the BIG mirror service in the UK: http://www.mirrorservice.org
*lightning surge protection* - a w_tom conductor

 

[Leif Neland]

Rod Speed sendte dette med sin computer:

Leif Neland <leif@neland.dk> wrote

So I hooked up the OBD-2 reader: Engine misfire cylinder 1.
I exchanged two "spark plug caps" which is really the ignition coil and
some electronics, one unit per cylinder.

Very unusual way to do things.

Here is the product page:

http://www.thansen.dk/product.asp?pn=-831477966

Price is USD 160, I got an used one for 24USD.

Alas, now it needs a new back door, because wife didn't see I parked
the Landcruiser outside the garage :-(

Leif

--
Husk křrelys bagpĺ, hvis din bilfabrikant har taget den idiotiske
beslutning at undlade det.

 

[Capitol]

Tim Watts wrote:

On 06/01/15 06:10, John Robertson wrote:

As usual, heat is the enemy. Reading the technical specs for caps is
enlightening. They are rated usually at something like 2,000 to 5,000
hours at their rated temperature. So an 80C cap will die after something
like 2000 hrs at 80C or 4000 hours at 50C and 10000 hours at 40C (not
looking it up!), whereas a 105C cap will last 10000 hours at 85C, etc.
So, the better the grade of cap the longer it will last in warm to hot
environments. And there is the equivalent resistance and inductance to
consider as well. Some caps are much more tolerant of 50/60hz and others
are better at 20,000hz. Selecting those takes time and the cost
accountants slip in at some point...

That's very interesting.

Based on this random driver circuit:

http://www.ecnmag.com/sites/ecnmag.com/files/legacyimages/ECN/Articles/2010/12/Fig%206-web(1).jpg


and looking at RS for 680uF around 50V electrolytics:

the 105C are around 50-70 pence
125C are around 130 pence
150C are 252 pence

There seems to be 1 big cap in that circuit - I don't have time now to
cost all of the electrolytics but this looks like a case of adding maybe
3 pounds would make the difference between a short life and a very long
life.

I suspect Philips use the good components - their LED bulbs seem to last
a long time (my tests are still pending) but they cost rather more than
3 pounds over the cheaper LEDs.

The things that kill electrolytic capacitors are ripple current and
ESR. If you double the capacitor size, the life dramatically increases
as the running temperature decreases. I once had a very nice DOS program
which forecast capacitor life extremely well based predominantly on
ripple current.

I see that Ford have had to add cooling fans to their infinite life LED
headlamps. I've never yet seen a fan with an infinite life!

 

[The Natural Philosopher]

On 06/01/15 11:22, Adrian Tuddenham wrote:

For a given energy storage capacity, capacitors are smaller, lighter and
cheaper than metal-cored chokes, but it is a lot more difficult to make
them as reliable in the long term.

a very cogent and pertinent statement


--
Everything you read in newspapers is absolutely true, except for the
rare story of which you happen to have first-hand knowledge. – Erwin Knoll

 

[tony sayer]

In article <NHHqw.502114$tr6.474642@fx15.am4>, Arfa Daily
<arfa.daily@ntlworld.com> scribeth thus

"Rod Speed" <rod.speed.aaa@gmail.com> wrote in message
news:cgubooFnch2U1@mid.individual.net...
Some gutless fuckwit desperately cowering behind
Arfa Daily <arfa.daily@ntlworld.com> wrote just the
puerile shit that always pours from the back of it when its got done like
a fucking dinner, as it always is by everyone.

Everybody who matters knows exactly who I am. You are just not one who
*does* matter Rod. The email address is valid. I'm sure if you were clever
enough to be able to look it up, you could get me right down to a street
address. As for me writing puerile shit, the words pot, kettle and black
come to mind. Most of what you write is *total* shit that no one wants to
hear, and frequently tell you so. But you are so full of yourself and your
opinionated crap, that it all goes over your head. Much like certain other
of your countrymen, as soon as anyone dares to call you out on your mindless
pontifications, you just revert to type, and start screaming bucket-mouthed
abuse. Why don't you just do everyone a big favour, and piss off for another
six months like you often do. And where are you when you do disappear ? In
jail, with any luck ...

Arfa

- or Geoff, if you prefer

Don't know why you bother with him Arfa, just killfile the prat thats
what I did ages ago!...
--
Tony Sayer

 

[Rod Speed]

Adrian Tuddenham <adrian@poppyrecords.invalid.invalid> wrote

The Natural Philosopher <tnp@invalid.invalid> wrote

Ergo these days we rectify, smooth and chop and transform at much
higher freqs than 50hz to get power at different voltages or to achieve
current limiting. And that gets rid of 100hz flicker too..or should,

The flicker will only disappear if you use a large capacitor as
a storage element; usually this is found on the HV side of the
inverter. This brings back the reliability problem: it is asking
a lot of a big capacitor to survive for many years

PC power supplys done like that last fine.

when it is potentially exposed to occasional
mains glitches from one side

It isnt hard to stop those getting to the cap.

and continuously exposed to the
switching current waveform on the other.

That doesn’t happen either with the big cap.

For a given energy storage capacity, capacitors are smaller,
lighter and cheaper than metal-cored chokes, but it is a lot
more difficult to make them as reliable in the long term.

Yes, but in practice its long term enough with PC power supplys.

 

[Rod Speed]

Leif Neland <leif@neland.dk> wrote

Rod Speed wrote
Leif Neland <leif@neland.dk> wrote

So I hooked up the OBD-2 reader: Engine misfire cylinder 1.
I exchanged two "spark plug caps" which is really the
ignition coil and some electronics, one unit per cylinder.

Very unusual way to do things.

Here is the product page:

http://www.thansen.dk/product.asp?pn=-831477966

Price is USD 160, I got an used one for 24USD.

I have considered the Yaris but don't thing I'll ever get one
given that approach. I've got a Hyundai Getz myself but likely
won't be replacing it unless it breaks dramatically. The previous
VW Golf lasted me 35+ years and I only needed to replace that
when I was stupid enough to no do anything about a known
windscreen leak after a windscreen replacement and that
eventually rusted out the floor and I could be arsed fixing that.

Alas, now it needs a new back door, because wife didn't
see I parked the Landcruiser outside the garage :-(

Should be able to get one of those cheap too given that
most of the writeoffs would be at the other end of the car.

 

[Adrian Tuddenham]

Rod Speed <rod.speed.aaa@gmail.com> wrote:

Adrian Tuddenham <adrian@poppyrecords.invalid.invalid> wrote
[...]
For a given energy storage capacity, capacitors are smaller,
lighter and cheaper than metal-cored chokes, but it is a lot
more difficult to make them as reliable in the long term.

Yes, but in practice its long term enough with PC power supplys.

....but not when the PSUs also have to fit into the cap of a light bulb
and under-cut the price of the nearest rival.


--
~ Adrian Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk

 

[Leif Neland]

Rod Speed forklarede den 06-01-2015:

Leif Neland <leif@neland.dk> wrote
Rod Speed wrote
Leif Neland <leif@neland.dk> wrote

So I hooked up the OBD-2 reader: Engine misfire cylinder 1.
I exchanged two "spark plug caps" which is really the ignition coil and
some electronics, one unit per cylinder.

Very unusual way to do things.

Here is the product page:

http://www.thansen.dk/product.asp?pn=-831477966

Price is USD 160, I got an used one for 24USD.

I have considered the Yaris but don't thing I'll ever get one given that
approach.

I find it a good approach, omitting a distributor and 5 cables which
can be attacked by moisture.
Here everything high voltage is sitting nice and dry almost inside the
engine, below a plastic cover.

I've got a Hyundai Getz myself but likely
won't be replacing it unless it breaks dramatically. The previous
VW Golf lasted me 35+ years and I only needed to replace that
when I was stupid enough to no do anything about a known
windscreen leak after a windscreen replacement and that eventually rusted out
the floor and I could be arsed fixing that.

Alas, now it needs a new back door, because wife didn't see I parked the
Landcruiser outside the garage :-(

Should be able to get one of those cheap too given that
most of the writeoffs would be at the other end of the car.

I've sent off enquries to two dealers, including a whole car with front
damage for for 1000USD.

Leif

--
Husk křrelys bagpĺ, hvis din bilfabrikant har taget den idiotiske
beslutning at undlade det.