CFL ballast design, and using dead lamps for repair

On Tue, 22 Jan 2013 16:44:06 -0000, "Ian Field"
<gangprobing.alien@ntlworld.com> wrote:

"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:am6fp5Ffc35U1@mid.individual.net...

dagmargoodboat@yahoo.com

FWIW, of the modest pile of CFLs I autopsied from my own house, 100%
of the failures were from failed heaters.

** Most CFLs have PTC thermistors that increase current flow to the heater
for the first few seconds - makes the lamp start quickly, particularly in
cool weather conditions.

It also burns out the heater in a few hundred or so cycles.

Claims for life spans of 6 or 8 thousand hours are based on continuous use
in a cool environment - plus lotsa good luck.


This may be atypical. I get good service from CFLs running them
without enclosures; the enclosed, base-up fail modes may be different.


** Recently, a neighbour had an 18W CFL explode and bits go all over the
kitchen - it was base up in a non ventilated fitting.

Must've been a pretty big explosion for bits to go everywhere from a
non-ventilated fitting!

Can lights aren't ventilated. In fact, many are insulated (IC rated).
They're hell on CFLs.

 

[Phil Allison]

"Ian Field" <

"Phil Allison"
dagmargoodboat@yahoo.com

FWIW, of the modest pile of CFLs I autopsied from my own house, 100%
of the failures were from failed heaters.

** Most CFLs have PTC thermistors that increase current flow to the
heater for the first few seconds - makes the lamp start quickly,
particularly in cool weather conditions.

It also burns out the heater in a few hundred or so cycles.

Claims for life spans of 6 or 8 thousand hours are based on continuous
use in a cool environment - plus lotsa good luck.


This may be atypical. I get good service from CFLs running them
without enclosures; the enclosed, base-up fail modes may be different.


** Recently, a neighbour had an 18W CFL explode and bits go all over the
kitchen - it was base up in a non ventilated fitting.

Must've been a pretty big explosion for bits to go everywhere from a
non-ventilated fitting!

** See the second half of this page for pics of the actual CFL and fitting.

http://sound.westhost.com/articles/il-cfl-6.htm

The are no ventilation a holes at the back of the fitting and all the spiral
CFLs were a neat fit.



.... Phil

 

[legg]

On Mon, 21 Jan 2013 04:04:24 -0500, "P E Schoen" <paul@peschoen.com>
wrote:

I have a desk lamp, with a magnifier and a 12W T4 circline fluorescent bulb,
that I use constantly for working on PCBs and electronics projects in
general. I bought it several years ago and recently it started flickering
and then died. I replaced the bulb, but still no joy, and after replacing
the blown fuse and two damaged transistors, I found that the little
transformer had an open winding.

So, I thought, a 60W equivalent CFL is actually about 11-13 watts, and the
little circuit in them should work. I had a couple of broken or dead bulbs
ready for recycling, so I opened the bases, cut the leads, and extracted the
PCBs. After a few unsuccessful tries, I was able to get it to work and now
my lamp is once again operational.

I found some schematics of the CFL driver boards here:
http://www.pavouk.org/hw/lamp/en_index.html

Some of those circuits matched what I had almost exactly. It was a little
difficult to follow the explanation of how they operate, but what was
confusing is the four pins shown on the lamp itself, which is also how the
bulbs are made. I assume they are the heaters that are usually activated
with a starter, but I did not find any continuity on those pins. The desk
lamp only had one wire to each of two pins on the circline bulb, but in the
CFLs all four wires were connected to different points on the PCB. It would
only work when I shorted the connections that would have gone to the
heaters, and it seems to work very well. It starts to light at 50 VAC and
reaches full brightness at 100-120V, at which it draws about 100mA. That's
close enough to 12 watts for me!

One other thing you can learn from this exercise - low cost part
types.

Typical gapped core sizes commonly used in this application can be
designed in elsewhere for $0.02. Similar price ranges for bobbins,
semiconductors, film caps, fuses and electrolytics.

Lots of other things you can do with this stuff, knowing you won't be
beat on material cost.

RL

 

[Ian Field]

"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:am976iF3phoU1@mid.individual.net...

"Ian Field"
"Phil Allison"
dagmargoodboat@yahoo.com

FWIW, of the modest pile of CFLs I autopsied from my own house, 100%
of the failures were from failed heaters.

** Most CFLs have PTC thermistors that increase current flow to the
heater for the first few seconds - makes the lamp start quickly,
particularly in cool weather conditions.

It also burns out the heater in a few hundred or so cycles.

Claims for life spans of 6 or 8 thousand hours are based on continuous
use in a cool environment - plus lotsa good luck.


This may be atypical. I get good service from CFLs running them
without enclosures; the enclosed, base-up fail modes may be different.


** Recently, a neighbour had an 18W CFL explode and bits go all over the
kitchen - it was base up in a non ventilated fitting.

Must've been a pretty big explosion for bits to go everywhere from a
non-ventilated fitting!

** See the second half of this page for pics of the actual CFL and
fitting.

http://sound.westhost.com/articles/il-cfl-6.htm

The are no ventilation a holes at the back of the fitting and all the
spiral CFLs were a neat fit.

Even stupid people should know better than put CFLs in a fitting like that!

 

[Spehro Pefhany]

On Wed, 23 Jan 2013 16:41:16 -0000, "Ian Field"
<gangprobing.alien@ntlworld.com> wrote:

"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:am976iF3phoU1@mid.individual.net...

"Ian Field"
"Phil Allison"
dagmargoodboat@yahoo.com

FWIW, of the modest pile of CFLs I autopsied from my own house, 100%
of the failures were from failed heaters.

** Most CFLs have PTC thermistors that increase current flow to the
heater for the first few seconds - makes the lamp start quickly,
particularly in cool weather conditions.

It also burns out the heater in a few hundred or so cycles.

Claims for life spans of 6 or 8 thousand hours are based on continuous
use in a cool environment - plus lotsa good luck.


This may be atypical. I get good service from CFLs running them
without enclosures; the enclosed, base-up fail modes may be different.


** Recently, a neighbour had an 18W CFL explode and bits go all over the
kitchen - it was base up in a non ventilated fitting.

Must've been a pretty big explosion for bits to go everywhere from a
non-ventilated fitting!

** See the second half of this page for pics of the actual CFL and
fitting.

http://sound.westhost.com/articles/il-cfl-6.htm

The are no ventilation a holes at the back of the fitting and all the
spiral CFLs were a neat fit.


Even stupid people should know better than put CFLs in a fitting like that!

I must be stupid then. I've got a CFL in a totally sealed (shower)
fixture and it's been working fine for years. (I even conformally
coated the lamp before sealing it in the fixture).

I only buy name brand (eg. Philips) products though, and probably
they're made a bit better than the ones that come 8 to a card. Never
seen any perforation of the housings on failure.

 

[David Eather]

On Thu, 24 Jan 2013 03:04:10 +1000, Spehro Pefhany
<speffSNIP@interlogdotyou.knowwhat> wrote:

On Wed, 23 Jan 2013 16:41:16 -0000, "Ian Field"
gangprobing.alien@ntlworld.com> wrote:



"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:am976iF3phoU1@mid.individual.net...

"Ian Field"
"Phil Allison"
dagmargoodboat@yahoo.com

FWIW, of the modest pile of CFLs I autopsied from my own house, 100%
of the failures were from failed heaters.

** Most CFLs have PTC thermistors that increase current flow to the
heater for the first few seconds - makes the lamp start quickly,
particularly in cool weather conditions.

It also burns out the heater in a few hundred or so cycles.

Claims for life spans of 6 or 8 thousand hours are based on
continuous
use in a cool environment - plus lotsa good luck.


This may be atypical. I get good service from CFLs running them
without enclosures; the enclosed, base-up fail modes may be
different.


** Recently, a neighbour had an 18W CFL explode and bits go all over
the
kitchen - it was base up in a non ventilated fitting.

Must've been a pretty big explosion for bits to go everywhere from a
non-ventilated fitting!

** See the second half of this page for pics of the actual CFL and
fitting.

http://sound.westhost.com/articles/il-cfl-6.htm

The are no ventilation a holes at the back of the fitting and all the
spiral CFLs were a neat fit.


Even stupid people should know better than put CFLs in a fitting like
that!

I must be stupid then. I've got a CFL in a totally sealed (shower)
fixture and it's been working fine for years. (I even conformally
coated the lamp before sealing it in the fixture).

I only buy name brand (eg. Philips) products though, and probably
they're made a bit better than the ones that come 8 to a card. Never
seen any perforation of the housings on failure.

Nope. I lost three Philips to one power surge and on pulling them apart I
can confirm they use the same caps or worse - mine were marked as 350V DC.
Considering the mains was 240v AC thats not a lot of a safety margin. I
now use whatever is cheapest seeing as it makes no difference to the
quality.

 

[Ian Field]

"David Eather" <eather@tpg.com.au> wrote in message
newsp.wrdk0ae1wei6gd@phenom-pc...

On Thu, 24 Jan 2013 03:04:10 +1000, Spehro Pefhany
speffSNIP@interlogdotyou.knowwhat> wrote:

On Wed, 23 Jan 2013 16:41:16 -0000, "Ian Field"
gangprobing.alien@ntlworld.com> wrote:



"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:am976iF3phoU1@mid.individual.net...

"Ian Field"
"Phil Allison"
dagmargoodboat@yahoo.com

FWIW, of the modest pile of CFLs I autopsied from my own house, 100%
of the failures were from failed heaters.

** Most CFLs have PTC thermistors that increase current flow to the
heater for the first few seconds - makes the lamp start quickly,
particularly in cool weather conditions.

It also burns out the heater in a few hundred or so cycles.

Claims for life spans of 6 or 8 thousand hours are based on
continuous
use in a cool environment - plus lotsa good luck.


This may be atypical. I get good service from CFLs running them
without enclosures; the enclosed, base-up fail modes may be
different.


** Recently, a neighbour had an 18W CFL explode and bits go all over
the
kitchen - it was base up in a non ventilated fitting.

Must've been a pretty big explosion for bits to go everywhere from a
non-ventilated fitting!

** See the second half of this page for pics of the actual CFL and
fitting.

http://sound.westhost.com/articles/il-cfl-6.htm

The are no ventilation a holes at the back of the fitting and all the
spiral CFLs were a neat fit.


Even stupid people should know better than put CFLs in a fitting like
that!

I must be stupid then. I've got a CFL in a totally sealed (shower)
fixture and it's been working fine for years. (I even conformally
coated the lamp before sealing it in the fixture).

I only buy name brand (eg. Philips) products though, and probably
they're made a bit better than the ones that come 8 to a card. Never
seen any perforation of the housings on failure.


Nope. I lost three Philips to one power surge and on pulling them apart I
can confirm they use the same caps or worse - mine were marked as 350V DC.
Considering the mains was 240v AC thats not a lot of a safety margin.

In a TV or monitor you'd find 385V minimum, more likely 400V. Although
nowadays with PFC front ends, there's no rectifier-reservoir electrolytic,
the PFC unit is essentially a boost converter, so the main electrolytic
would be about 450V.

 

[Spehro Pefhany]

On Thu, 24 Jan 2013 03:46:48 +1000, "David Eather" <eather@tpg.com.au>
wrote:

Nope. I lost three Philips to one power surge and on pulling them apart I
can confirm they use the same caps or worse - mine were marked as 350V DC.
Considering the mains was 240v AC thats not a lot of a safety margin. I
now use whatever is cheapest seeing as it makes no difference to the
quality.

Parts that are marked the same are not necessarily the same. The $1.00
bulbs may contain gold-colored caps marked as 630VDC/125°C.

http://www.discovercircuits.com/dc-mag/Issue_4/Photos/FakeCapacitor1.jpg

Not sure if the 240V input makes much difference.. they are likely
using a doubler circuit in our (120V) lamps.

I have heard enough stories of people who bought the cheap ones and
had initial failures, exciting failures, and such like to avoid the
low end stuff.

It would be nice if LED lamps got anywhere close to the brightness of
CFL, halogen or incandescent bulbs at a reasonable price, but they are
not very close yet. Maybe in a few years. I bought a couple MR11
"brightest on the market" bulbs to unload the halogen xfmr and allow
me to put a bigger halogen in the centre bulb of a 3-light string, and
they're not even comparable. I'll have to take some quantitative
measurements at some point.

 

[Ian Field]

"Spehro Pefhany" <speffSNIP@interlogDOTyou.knowwhat> wrote in message
news:s6c0g8pgpjgmhg6dck0nrsq5csvpggofq8@4ax.com...

On Thu, 24 Jan 2013 03:46:48 +1000, "David Eather" <eather@tpg.com.au
wrote:


Nope. I lost three Philips to one power surge and on pulling them apart I
can confirm they use the same caps or worse - mine were marked as 350V DC.
Considering the mains was 240v AC thats not a lot of a safety margin. I
now use whatever is cheapest seeing as it makes no difference to the
quality.

Parts that are marked the same are not necessarily the same. The $1.00
bulbs may contain gold-colored caps marked as 630VDC/125°C.

http://www.discovercircuits.com/dc-mag/Issue_4/Photos/FakeCapacitor1.jpg

Not sure if the 240V input makes much difference.. they are likely
using a doubler circuit in our (120V) lamps.

I have heard enough stories of people who bought the cheap ones and
had initial failures, exciting failures, and such like to avoid the
low end stuff.

It would be nice if LED lamps got anywhere close to the brightness of
CFL, halogen or incandescent bulbs at a reasonable price, but they are
not very close yet. Maybe in a few years. I bought a couple MR11
"brightest on the market" bulbs to unload the halogen xfmr and allow
me to put a bigger halogen in the centre bulb of a 3-light string, and
they're not even comparable. I'll have to take some quantitative
measurements at some point.

Last time I saw LED "bulbs" in the supermarket, they were significantly less
lumen/W, several times the price and you'd need at least 3 (at 9W each) to
equal the light output of an 18W CFL.

LED lighting in the style similar to LV halogen type is supposedly up to the
job.

 

[Spehro Pefhany]

On Wed, 23 Jan 2013 19:40:37 -0000, "Ian Field"
<gangprobing.alien@ntlworld.com> wrote:

LED lighting in the style similar to LV halogen type is supposedly up to the
job.

Lumens per watt is probably okay. The problem is that they're using
discrete SMT LEDs and the $ per incremental lumen is far more than for
a CFL.

These are the ones I bought.
http://www.amazon.com/gp/product/B007DA05O6/ref=oh_details_o00_s00_i00

I'd prefer to have 50W or 100W equivalent that burns 5 or 10W.

 

[Spehro Pefhany]

On Wed, 23 Jan 2013 13:00:38 -0800 (PST), George Herold
<gherold@teachspin.com> wrote:

Nice artcile Phil, But don't worry about the legislature's doing
anything. What's needed is some lawayer to get a hold of it and sue
the manufacturers.

(That's the US way :^)

George H.

The offshore manufacturers are probably not easy to get substantial
judgements against- but the stores, especially those who do their own
importing, have deep pockets and can't easily escape.

They do have a good defense though- if it has safety agency approval,
it's presumed to be safe. Maybe report it to the safety agencies- but
I don't see anthing there that would really raise the alarm-
incadescents break and short internally and implode from time to time,
and none of the burn- through incidents shows support of combustion.
Any fixture designed for a normal incandescent ought not to burn the
office or house down. The one that 'exploded' is the closest one- the
mfr may have substituted a cheaper non-fiberglass sleeving on that
diode.

 

[Spehro Pefhany]

On Wed, 23 Jan 2013 16:44:01 -0500, Spehro Pefhany
<speffSNIP@interlogDOTyou.knowwhat> wrote:

On Wed, 23 Jan 2013 13:00:38 -0800 (PST), George Herold
gherold@teachspin.com> wrote:


Nice artcile Phil, But don't worry about the legislature's doing
anything. What's needed is some lawayer to get a hold of it and sue
the manufacturers.

(That's the US way :^)

George H.


The offshore manufacturers are probably not easy to get substantial
judgements against- but the stores, especially those who do their own
importing, have deep pockets and can't easily escape.

They do have a good defense though- if it has safety agency approval,
it's presumed to be safe. Maybe report it to the safety agencies- but
I don't see anthing there that would really raise the alarm-
incadescents break and short internally and implode from time to time,
and none of the burn- through incidents shows support of combustion.
Any fixture designed for a normal incandescent ought not to burn the
office or house down. The one that 'exploded' is the closest one- the
mfr may have substituted a cheaper non-fiberglass sleeving on that
diode.

P.S.

http://www.cpsc.gov/cpscpub/prerel/prhtml11/11001.html

Sold at: Discount stores in New York, New Jersey, Pennsylvania and
Connecticut from January 2008 to December 2008 for between $1 and
$1.50.

Manufactured in: China

 

[George Herold]

On Jan 22, 11:28 pm, "Phil Allison" <phi...@tpg.com.au> wrote:

"Ian Field"





"Phil Allison"
dagmargoodb...@yahoo.com

FWIW, of the modest pile of CFLs I autopsied from my own house, 100%
of the failures were from failed heaters.

** Most CFLs have PTC thermistors that increase current flow to the
heater for the first few seconds -  makes the lamp start quickly,
particularly in cool weather conditions.

It also burns out the heater in a few hundred or so cycles.

Claims for life spans of 6 or 8 thousand hours are based on continuous
use in a cool environment -  plus lotsa good luck.

This may be atypical.  I get good service from CFLs running them
without enclosures; the enclosed, base-up fail modes may be different..

** Recently, a neighbour had an 18W CFL explode and bits go all over the
kitchen - it was base up in a non ventilated fitting.

Must've been a pretty big explosion for bits to go everywhere from a
non-ventilated fitting!

** See the second half of this page for pics of the actual CFL and fitting.

http://sound.westhost.com/articles/il-cfl-6.htm

The are no ventilation a holes at the back of the fitting and all the spiral
CFLs were a neat fit.

Nice artcile Phil, But don't worry about the legislature's doing
anything. What's needed is some lawayer to get a hold of it and sue
the manufacturers.

(That's the US way :^)

George H.

...   Phil- Hide quoted text -

- Show quoted text -

 

[Phil Allison]

"Spehro Pefhany"

"Phil Allison"

** Recently, a neighbour had an 18W CFL explode and bits go all over
the
kitchen - it was base up in a non ventilated fitting.

Must've been a pretty big explosion for bits to go everywhere from a
non-ventilated fitting!

** See the second half of this page for pics of the actual CFL and
fitting.

http://sound.westhost.com/articles/il-cfl-6.htm

The are no ventilation a holes at the back of the fitting and all the
spiral CFLs were a neat fit.


I only buy name brand (eg. Philips) products though, and probably
they're made a bit better than the ones that come 8 to a card. Never
seen any perforation of the housings on failure.

** The plastic bases of most CFLs simply push fit together - so only a
small explosion inside will blow the top part off.

Small bits of glass were strewn from one end of the kitchen to the other (
when I arrived with my camera ) and some bits had landed on the benches -
so it seemed the spiral tube must have exploded in mid air. The filaments
were both intact so the only explanation I have is that the glass spiral
impacted hard against the inside of the lamp fitting before falling in
pieces.


.... Phil

 

[Doug White]

Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> wrote in
news:s6c0g8pgpjgmhg6dck0nrsq5csvpggofq8@4ax.com:

<snip>

It would be nice if LED lamps got anywhere close to the brightness of
CFL, halogen or incandescent bulbs at a reasonable price, but they are
not very close yet. Maybe in a few years. I bought a couple MR11
"brightest on the market" bulbs to unload the halogen xfmr and allow
me to put a bigger halogen in the centre bulb of a 3-light string, and
they're not even comparable. I'll have to take some quantitative
measurements at some point.

If you want relatively unbiased & consitent tests of LED bulbs, check
out:

http://www1.eere.energy.gov/buildings/ssl/caliper.html

You have to promise that you aren't a commercial operation to see the
full reports. The reports tend to lag a bit behind the latest
technology, but the quality is going up & the prices are coming down.

I have a couple of LED bulbs in special applications, and they work very
nicely. I use a couple MR-16 replacements in gooseneck illuminators on
my milling machine because I got tired of toasting myself with the
halogen bulbs. I've also installed these:

http://www.homedepot.com/h_d1/N-5yc1v/R-202240932/h_d2/ProductDisplay?
catalogId=10053&langId=-1#.UQBxHfIT_To

in stairwells where I want instant full brightness. They work great.
They also actually cost a lot less than the dimmable CFL retrofit units I
installed a number of years ago.

Doug White

 

[George Herold]

On Jan 23, 4:44 pm, Spehro Pefhany <speffS...@interlogDOTyou.knowwhat>
wrote:

On Wed, 23 Jan 2013 13:00:38 -0800 (PST), George Herold

gher...@teachspin.com> wrote:

Nice artcile Phil,  But don't worry about the legislature's doing
anything.  What's needed is some lawayer to get a hold of it and sue
the manufacturers.

(That's the US way :^)

George H.

The offshore manufacturers are probably not easy to get substantial
judgements against- but the stores, especially those who do their own
importing, have deep pockets and can't easily escape.

Grin sure sue everyone,

They do have a good defense though- if it has safety agency approval,
it's presumed to be safe. Maybe report it to the safety agencies- but
I don't see anthing there that would really raise the alarm-
incadescents break and short internally and implode from time to time,
and none of the burn- through incidents shows support of combustion.
Any fixture designed for a normal incandescent ought not to burn the
office or house down. The one that 'exploded' is the closest one- the
mfr may have substituted a cheaper non-fiberglass sleeving on that
diode.

OK maybe it will be the insurance company lawyers sueing for fire
damage.

I haven't had many problems with cfl's, except for globe units in the
(steamy?) bathroom.

George H.

 

[Spehro Pefhany]

On Thu, 24 Jan 2013 09:45:44 +1100, the renowned "Phil Allison"
<phil_a@tpg.com.au> wrote:

** The plastic bases of most CFLs simply push fit together - so only a
small explosion inside will blow the top part off.

If they come apart easily by pulling and expose the mains potential, I
would not think that would pass muster with the safety agencies. It's
been a while since I've tried to take one part, but I recall whole
rows of snaps that are not easy to disengage.

Does Australia enforce national safety standards on the sale of
mains-powered goods?

Small bits of glass were strewn from one end of the kitchen to the other (
when I arrived with my camera ) and some bits had landed on the benches -
so it seemed the spiral tube must have exploded in mid air. The filaments
were both intact so the only explanation I have is that the glass spiral
impacted hard against the inside of the lamp fitting before falling in
pieces.


... Phil

Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

 

[Ian Field]

"Spehro Pefhany" <speffSNIP@interlogDOTyou.knowwhat> wrote in message
news:77g2g8lhtv08d3k09mhpfnuk1j9h8jol82@4ax.com...

On Thu, 24 Jan 2013 09:45:44 +1100, the renowned "Phil Allison"
phil_a@tpg.com.au> wrote:


** The plastic bases of most CFLs simply push fit together - so only a
small explosion inside will blow the top part off.

If they come apart easily by pulling and expose the mains potential, I
would not think that would pass muster with the safety agencies. It's
been a while since I've tried to take one part, but I recall whole
rows of snaps that are not easy to disengage.

Many of the early types sold in the UK were fairly easy to pry open and
could be clipped together again easily - the most recent Philips one's I
bought are much more secure - you pretty much have to destroy the case to
pry it open.

 

[Phil Allison]

"Spehro Pefhany"

"Phil Allison"

** The plastic bases of most CFLs simply push fit together - so only a
small explosion inside will blow the top part off.

If they come apart easily by pulling and expose the mains potential,

** See the word "explosion " ??

A tool ( ie screwdriver) is needed to open most CFLs and that is adequate
to pass safety rules anywhere.


.... Phil

 

[Spehro Pefhany]

On Fri, 25 Jan 2013 10:20:29 +1100, the renowned "Phil Allison"
<phil_a@tpg.com.au> wrote:

"Spehro Pefhany"
"Phil Allison"

** The plastic bases of most CFLs simply push fit together - so only a
small explosion inside will blow the top part off.

If they come apart easily by pulling and expose the mains potential,


** See the word "explosion " ??

An explosion like "pop rocks" or an explosion like Bikini atoll? Maybe
your mains has more oomph, but I've not seen anything that would blow
apart a proper housing from a residential power line.

A tool ( ie screwdriver) is needed to open most CFLs and that is adequate
to pass safety rules anywhere.


... Phil

Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com