Burn Down Your House With LED's!

[DougC]

--or MY house, perhaps.....
I have an outdoor light fixture that seems to destroy regular light
bulbs on a fairly regular basis--about two weeks is the longest that any
lights seem to last, no matter what type I buy. SO what I am wondering
is if I can make a LED-bulb: I am thinking a full-wave rectifier, then 8
or 10 LED's in series with a dropping resistor. Of course I'd use 40-50+
or so LED's, but no more than 8 or 10 [in series] on a single dropping
resistor. I am in the US, with 120V/60 htz wall current. I would likely
use trim pots and start with the resistors high and lower them until the
LED's are looking about right, then check the current to make sure I'm
not risking incineration, but what do white LED's draw, 20 ma?.... I
have seen the ones for sale online and they are very expensive, but I
don't know what's inside them. And I am willing to accept that the LED
light I make myself may not be quite as bright as a regular bulb or a
high-priced replacement LED fixture, but if the led's are left standing,
they could be bent down towards the ground somewhat. And a smaller
amount of dependable light is better than no light at all, which is what
I get after a couple weeks anyway. After spending $30 or so in three
months on failing light bulbs, coughing up $40 or so for some LED's that
will last ten years sounds like a pretty good deal.
------
Is there anything drastically wrong with this idea?

 

[Myron Samila]

"DougC" <dcimperg@norcom2000.com> wrote in message
news:103mjvulhqcaa10@corp.supernews.com...

--or MY house, perhaps.....
I have an outdoor light fixture that seems to destroy regular light
bulbs on a fairly regular basis--about two weeks is the longest that any
lights seem to last, no matter what type I buy. SO what I am wondering
is if I can make a LED-bulb: I am thinking a full-wave rectifier, then 8
or 10 LED's in series with a dropping resistor. Of course I'd use 40-50+
or so LED's, but no more than 8 or 10 [in series] on a single dropping

resistor. I am in the US, with 120V/60 htz wall current. I would likely
use trim pots and start with the resistors high and lower them until the
LED's are looking about right, then check the current to make sure I'm
not risking incineration, but what do white LED's draw, 20 ma?.... I
have seen the ones for sale online and they are very expensive, but I
don't know what's inside them. And I am willing to accept that the LED
light I make myself may not be quite as bright as a regular bulb or a
high-priced replacement LED fixture, but if the led's are left standing,
they could be bent down towards the ground somewhat. And a smaller
amount of dependable light is better than no light at all, which is what
I get after a couple weeks anyway. After spending $30 or so in three
months on failing light bulbs, coughing up $40 or so for some LED's that > will last ten
years sounds like a pretty good deal.
------
Is there anything drastically wrong with this idea?

White LEDs are quite expensive at the moment, and they don't last as long as regular LEDs
in the "white" colour spectrum. They are made with blue LEDs and a yellow phosphor. They
are also not as efficient at the moment as fluorescent lamps as far as output goes (lm/W).

I also have an outdoor light fixture, and I chose a "warm" white colour spectrum
fluorescent lamp (screw base) and it works great. I installed it about 4 years ago, and
it is on almost every night for about 4-5 hours. It takes a while to warm up when it is
cold outside, but otherwise, it is great. I used tungsten lamps before, and they
constantly were burning out.

I'd try the UL approved approach first, and actually, you can already buy screw base LED
illuminated lamps at a decent price.


--
Myron Samila
Toronto, ON Canada
Samila Racing
http://204.101.251.229/myronx19

 

[Dave]

"Myron Samila" <myronx19@no.spam.sympatico.ca> wrote in message
news:VEM_b.4381$ee3.283532@news20.bellglobal.com...

"DougC" <dcimperg@norcom2000.com> wrote in message
news:103mjvulhqcaa10@corp.supernews.com...
--or MY house, perhaps.....
I have an outdoor light fixture that seems to destroy regular light
bulbs on a fairly regular basis--about two weeks is the longest that any
lights seem to last, no matter what type I buy. SO what I am wondering
is if I can make a LED-bulb: I am thinking a full-wave rectifier, then 8
or 10 LED's in series with a dropping resistor. Of course I'd use 40-50+
or so LED's, but no more than 8 or 10 [in series] on a single dropping

resistor. I am in the US, with 120V/60 htz wall current. I would likely
use trim pots and start with the resistors high and lower them until the
LED's are looking about right, then check the current to make sure I'm
not risking incineration, but what do white LED's draw, 20 ma?.... I
have seen the ones for sale online and they are very expensive, but I
don't know what's inside them. And I am willing to accept that the LED
light I make myself may not be quite as bright as a regular bulb or a
high-priced replacement LED fixture, but if the led's are left standing,
they could be bent down towards the ground somewhat. And a smaller
amount of dependable light is better than no light at all, which is what
I get after a couple weeks anyway. After spending $30 or so in three
months on failing light bulbs, coughing up $40 or so for some LED's that
will last ten
years sounds like a pretty good deal.
------
Is there anything drastically wrong with this idea?



White LEDs are quite expensive at the moment, and they don't last as long
as regular LEDs
in the "white" colour spectrum. They are made with blue LEDs and a yellow
phosphor. They
are also not as efficient at the moment as fluorescent lamps as far as
output goes (lm/W).

I also have an outdoor light fixture, and I chose a "warm" white colour
spectrum
fluorescent lamp (screw base) and it works great. I installed it about 4
years ago, and
it is on almost every night for about 4-5 hours. It takes a while to warm
up when it is
cold outside, but otherwise, it is great. I used tungsten lamps before,
and they
constantly were burning out.

I'd try the UL approved approach first, and actually, you can already buy
screw base LED
illuminated lamps at a decent price.


--
Myron Samila
Toronto, ON Canada
Samila Racing
http://204.101.251.229/myronx19

Yeah, flourescents last a long time, but if you live anywhere along the Gulf
Coast like I do they attract termites like crazy when they swarm in the
spring.

Dave
db5151@hotmail.com

 

[Don Bruder]

In article <c1g7kn$f3p@library2.airnews.net>,
"Dave" <dbeane@genie.idt.net> wrote:

Yeah, flourescents last a long time, but if you live anywhere along the Gulf
Coast like I do they attract termites like crazy when they swarm in the
spring.

And lotsa luck getting them to "fire up" below about 40 degrees if
you're anywhere it gets that cold.

--
Don Bruder - dakidd@sonic.net - New Email policy in effect as of Feb. 21, 2004.
For info on this, see <http://www.sonic.net/~dakidd/main/contact.html> Short
form: I'm trashing EVERYTHING that doesn't contain a specific, rotating phrase
in the subject line. Sorry, but spammers have forced me to take this action.

 

[Don Klipstein]

In article <JKQ_b.3548$_3.56485@typhoon.sonic.net>, Don Bruder wrote:

In article <c1g7kn$f3p@library2.airnews.net>,
"Dave" <dbeane@genie.idt.net> wrote:


Yeah, flourescents last a long time, but if you live anywhere along the Gulf
Coast like I do they attract termites like crazy when they swarm in the
spring.

And lotsa luck getting them to "fire up" below about 40 degrees if
you're anywhere it gets that cold.

Plenty of electronic-ballasted compact fluorescents fire up at zero or
colder, and "outdoor" types (and most other with outer bulbs over the
tubing) work down to about zero, give or take somewhat depending on wind
(they take cold better in enclosed fixtures). They may need several
minutes to warm up.
My favorite so far is the Philips 18 watt "Outdoor". In severe enough
cold it starts off-color (pinkish red, apparently from neon or a
neon-argon mixture, fair chance not requiring presence of mercury vapor to
start) but warms up amazingly after several minutes.

- Don Klipstein (don@misty.com, http://www.misty.com/~don/cfx.html)

 

[CWatters]

Does the bulb fail when it's switched on or after it's been on for a while?

If the latter then perhaps it'overheating? That could also be a problem for
60+ LEDs.

My vote would be to try a flourescent as they run cooler.




"DougC" <dcimperg@norcom2000.com> wrote in message
news:103mjvulhqcaa10@corp.supernews.com...

--or MY house, perhaps.....
I have an outdoor light fixture that seems to destroy regular light
bulbs on a fairly regular basis--about two weeks is the longest that any
lights seem to last, no matter what type I buy. SO what I am wondering
is if I can make a LED-bulb: I am thinking a full-wave rectifier, then 8
or 10 LED's in series with a dropping resistor. Of course I'd use 40-50+
or so LED's, but no more than 8 or 10 [in series] on a single dropping
resistor. I am in the US, with 120V/60 htz wall current. I would likely
use trim pots and start with the resistors high and lower them until the
LED's are looking about right, then check the current to make sure I'm
not risking incineration, but what do white LED's draw, 20 ma?.... I
have seen the ones for sale online and they are very expensive, but I
don't know what's inside them. And I am willing to accept that the LED
light I make myself may not be quite as bright as a regular bulb or a
high-priced replacement LED fixture, but if the led's are left standing,
they could be bent down towards the ground somewhat. And a smaller
amount of dependable light is better than no light at all, which is what
I get after a couple weeks anyway. After spending $30 or so in three
months on failing light bulbs, coughing up $40 or so for some LED's that
will last ten years sounds like a pretty good deal.
------
Is there anything drastically wrong with this idea?

 

[Jamie]

if its an order light, maybe you should start watching your neighbors.



DougC wrote:

--or MY house, perhaps.....
I have an outdoor light fixture that seems to destroy regular light
bulbs on a fairly regular basis--about two weeks is the longest that any
lights seem to last, no matter what type I buy. SO what I am wondering
is if I can make a LED-bulb: I am thinking a full-wave rectifier, then 8
or 10 LED's in series with a dropping resistor. Of course I'd use 40-50+
or so LED's, but no more than 8 or 10 [in series] on a single dropping
resistor. I am in the US, with 120V/60 htz wall current. I would likely
use trim pots and start with the resistors high and lower them until the
LED's are looking about right, then check the current to make sure I'm
not risking incineration, but what do white LED's draw, 20 ma?.... I
have seen the ones for sale online and they are very expensive, but I
don't know what's inside them. And I am willing to accept that the LED
light I make myself may not be quite as bright as a regular bulb or a
high-priced replacement LED fixture, but if the led's are left standing,
they could be bent down towards the ground somewhat. And a smaller
amount of dependable light is better than no light at all, which is what
I get after a couple weeks anyway. After spending $30 or so in three
months on failing light bulbs, coughing up $40 or so for some LED's that
will last ten years sounds like a pretty good deal.
------
Is there anything drastically wrong with this idea?

 

[Watson A.Name - \"Watt Su]

"DougC" <dcimperg@norcom2000.com> wrote in message
news:103mjvulhqcaa10@corp.supernews.com...

--or MY house, perhaps.....
I have an outdoor light fixture that seems to destroy regular light
bulbs on a fairly regular basis--about two weeks is the longest that
any
lights seem to last, no matter what type I buy. SO what I am wondering
is if I can make a LED-bulb: I am thinking a full-wave rectifier, then
8
or 10 LED's in series with a dropping resistor. Of course I'd use
40-50+
or so LED's, but no more than 8 or 10 [in series] on a single dropping
resistor. I am in the US, with 120V/60 htz wall current. I would
likely
use trim pots and start with the resistors high and lower them until
the
LED's are looking about right, then check the current to make sure I'm
not risking incineration, but what do white LED's draw, 20 ma?.... I
have seen the ones for sale online and they are very expensive, but I
don't know what's inside them. And I am willing to accept that the LED
light I make myself may not be quite as bright as a regular bulb or a
high-priced replacement LED fixture, but if the led's are left
standing,
they could be bent down towards the ground somewhat. And a smaller
amount of dependable light is better than no light at all, which is
what
I get after a couple weeks anyway. After spending $30 or so in three
months on failing light bulbs, coughing up $40 or so for some LED's
that
will last ten years sounds like a pretty good deal.
------
Is there anything drastically wrong with this idea?

A compact fluorescent light will last many times longer, and will cost
less than ten dollars. And it's a simple matter of screwing it into the
socket.

You can get white LEDs from http://www.whitelightled.com/, and the price
is only a dollar each. I've never had any problems with the more than
100 I've bought from him (just a satisfied customer). I bought a
hundred on ebay, and the 20 LED lamp I made and have had running for a
few months is now so dim that it has become useless. Two of the ten
LEDs have failed completely. They were only a quarter apiece, but I see
now that I got what I paid for, a _whole_lot_less quality.

If you order from the URL above, you can use the 50 degree for a wider
beam, or like you said, spread them out for a wider beam and use the 20
degree LEDs. White LEDs are not any more efficient than incandescent
lights, but last longer. You will need a circuit to limit the current,
and you can use 25 in series for about 85 to 90 volts drop, and connect
two strings anti-parallel so each lights up on each half of the AC
cycle. The dropping circuit can be a 100 ohm resistor, and a .47 uF X2
rated capacitor, both in series with the LEDs.

Also, you must leave space between the LEDs, or they will get too hot
and overheat, and fail soon after. Heat is their enemy!

But believe me, I'm speaking from experience, your best bet is to use a
regular compact fluorescent lamp instead. They're dirt cheap compared
to LEDs.

 

[Watson A.Name - \"Watt Su]

"Dave" <dbeane@genie.idt.net> wrote in message
news:c1g7kn$f3p@library2.airnews.net...
[snip]

Yeah, flourescents last a long time, but if you live anywhere along
the Gulf
Coast like I do they attract termites like crazy when they swarm in
the
spring.

Heh, well, that's _your_ problem. Maybe if you check out these facts,
you'll see why:

"The average number of insects in one square mile is more than all of
the people on earth. The total weight of arthropods in the world is
several times the total weight of all other land animals combined."

http://www.oznet.ksu.edu/entomology/extension/InsectID/introtoi.pdf

Dave
db5151@hotmail.com