Alternative Power sources - Designing Whole house LED night lights.

Author

Designing Whole house LED night lights.

Bughunter

2005-12-16, 10:21 am

The recent discussion about LED lighting included a couple comments on the
appropriateness of LEDS for night lights. I thought it was an idea worthy of
it's own thread.

My off grid home is in the stage of construction where the interior walls
are still open accessible to add wiring runs. So, now is an opportune time
for me to add wiring to the whole house. So far, I have not installed any
low voltage wiring runs, just the 115vac wring typical of a standard US
home.

I have been casually thinking about adding a dedicated low voltage DC
circuit to support some LED night lights as a simple aid to night
navigation. I have a few ideas, but have not made any decisions yet. Maybe I
can get some ideas here to influence me in one direction or another.

I'm interested in ideas on how I might set up LED night lights throughout
the house.
Right now, I use a few glass enclosed tea candles for night lights which is
romantic, but a little too 19th century. I want something that looks
professional, and not homemade.

My inverter runs in sleep mode at night, so I'd prefer a solution that does
not require 115vac except perhaps for periodic (and hopefully infrequent)
manual battery recharging.

I wonder if it would make sense to power the LED night lights from my main
48v battery bank, or to use a separate dedicated bank, and maybe at a
different voltage?

My main bank runs at 48v. I suppose it would be easy enough to run a
dedicated, fused, 48v wiring run..With a 48v run, I would not have as much
voltage drop across the wire and could use smaller gauge wire. But, would I
be just burning it off in resistors required to drop the voltage to that
required by the LEDs?

Alternatively, I could setup a separate 6v (or 12v) deep cycle golf cart
battery. This would require periodic recharging, probably with an
inexpensive automotive charger plugged into my 110vac. I'd almost prefer not
to go this route, because it adds one more thing separate subsystem to have
to monitor and maintain. On the other hand, if it were 12v, then I might
find it useful for other non-nightlight applications such as recharging my
cell phone where 12v is the more common voltage. DC to DC converters are
somewhat pricey, but I suppose for one or two low draw outlets it is a
possibility.

I am thinking that a single switch per floor would be adequate for my place.
I wonder if I could just use a normal 110vac light switch for 48VDC, or I
would need a DC rated switch?

It would be nice if I could use some small gauge wire, like Cat5, or door
bell wire. Each wire run might be in the range of 100 feet per floor.

My place is 2200 square feet, on two floors. I think 6 to 8 night-lights
fixtures per floor would provide adequate night lighting.

Is a single led per fixture adequate? Color?

Are there any off the shelf low voltage DC fixtures that might be
applicable. I don't want to reinvent the wheel if an off the shelf solution
exists, as long as it is no too expensive.

I wonder what kind of fixture could be made that would be simple to
construct, yet
not look homemade. One thought is to use a single outlet type mounting box,
and use a blank switch plate mount a led. Maybe more than one led per plate?

Ideas? Experiences? Links? Calculations?

George Ghio

2005-12-16, 11:21 am

Bughunter wrote:
> The recent discussion about LED lighting included a couple comments on the
> appropriateness of LEDS for night lights. I thought it was an idea worthy of
> it's own thread.
>
> My off grid home is in the stage of construction where the interior walls
> are still open accessible to add wiring runs. So, now is an opportune time
> for me to add wiring to the whole house. So far, I have not installed any
> low voltage wiring runs, just the 115vac wring typical of a standard US
> home.
>
> I have been casually thinking about adding a dedicated low voltage DC
> circuit to support some LED night lights as a simple aid to night
> navigation. I have a few ideas, but have not made any decisions yet. Maybe I
> can get some ideas here to influence me in one direction or another.
>
> I'm interested in ideas on how I might set up LED night lights throughout
> the house.
> Right now, I use a few glass enclosed tea candles for night lights which is
> romantic, but a little too 19th century. I want something that looks
> professional, and not homemade.
>
> My inverter runs in sleep mode at night, so I'd prefer a solution that does
> not require 115vac except perhaps for periodic (and hopefully infrequent)
> manual battery recharging.
>
> I wonder if it would make sense to power the LED night lights from my main
> 48v battery bank, or to use a separate dedicated bank, and maybe at a
> different voltage?
>
> My main bank runs at 48v. I suppose it would be easy enough to run a
> dedicated, fused, 48v wiring run..With a 48v run, I would not have as much
> voltage drop across the wire and could use smaller gauge wire. But, would I
> be just burning it off in resistors required to drop the voltage to that
> required by the LEDs?

Well if we say each LED needs 3V then 16 leds in series would use 48V.
No resistors.
>
> Alternatively, I could setup a separate 6v (or 12v) deep cycle golf cart
> battery. This would require periodic recharging, probably with an
> inexpensive automotive charger plugged into my 110vac. I'd almost prefer not
> to go this route, because it adds one more thing separate subsystem to have
> to monitor and maintain. On the other hand, if it were 12v, then I might
> find it useful for other non-nightlight applications such as recharging my
> cell phone where 12v is the more common voltage. DC to DC converters are
> somewhat pricey, but I suppose for one or two low draw outlets it is a
> possibility.
>
> I am thinking that a single switch per floor would be adequate for my place.
> I wonder if I could just use a normal 110vac light switch for 48VDC, or I
> would need a DC rated switch?

Switches depend on the load. I use standard 10A ac switches for most
lights. Hell,a 10 amp ac switch running less than an amp dc is not a
problem.
>
> It would be nice if I could use some small gauge wire, like Cat5, or door
> bell wire. Each wire run might be in the range of 100 feet per floor.
>
> My place is 2200 square feet, on two floors. I think 6 to 8 night-lights
> fixtures per floor would provide adequate night lighting.
>
> Is a single led per fixture adequate? Color?

Yes and white works fine or colour of your choice
>
> Are there any off the shelf low voltage DC fixtures that might be
> applicable. I don't want to reinvent the wheel if an off the shelf solution
> exists, as long as it is no too expensive.

All my lighting is ELV @ 12V. I rework standard light fittings to run;

LED lights, single LEDs or 18 LED lamps depending on use.

QH globes.

Dichroic Lamps.

Standard fluros with dedicated inverters.

All run with off the shelf fittings used in new ways.
>
> I wonder what kind of fixture could be made that would be simple to
> construct, yet
> not look homemade. One thought is to use a single outlet type mounting box,
> and use a blank switch plate mount a led. Maybe more than one led per plate?
>
> Ideas? Experiences? Links? Calculations?

I have used:

Rubber grommets as led bezels.

Here we have a fitting which allows you to drop a lamp from a ceiling
fitting. Magic, I just fit resistor and led into this and screw it into
the fixture.

PVC pipe to make lamps.

The tops of spray paint cans as reflectors for QH bulbs. Use flat white
paint for your reflectors, better than gloss white or silver.

You should get a fittings catalogue from electrical wholesale supplier
to the trade.

While you have the framing exposed is the best time to do your lighting.

I put up all my lighting at that stage. Some I moved 2 or 3 times to get
them in the right spot. I used a lot of lights. I have 15 in the kitchen
/dining alone. A mixture of QH, Dichroic and LED. They are placed for
best effect over work spaces.

The standard is a 60 or 100 watt lamp in the middle of a room. Dead loss.

Non of my lamps exceeds 20(Fluros) watts and most are either 5W(QH) or
10W(QH and Dichroic) And three, 18 LED lamps over the breakfast bar.

Bughunter

2005-12-16, 12:21 pm

"George Ghio" <AKA@nomailhere.com> wrote in message
news:43a2cfbd_3@news.chariot.net.au...
>
>
> Bughunter wrote:
>
> Well if we say each LED needs 3V then 16 leds in series would use 48V. No
> resistors.

But, I don't think I'd need 16 LEDs for a single night-light. I'm thinking
that 1-3 might be
enough (light-wise) for each fixture. I don't think that I want to run
series strings in the walls although it would be possible. It feels a little
like those series strings of xmas lights, where you had to search for the
bad bulb to fix a string. With the long life of LEDs, it would much less of
a problem. Maybe it does make more sense to just use 16 leds and get more
light rather than just disipating the power in resistors as heat.
[color=darkred]
>
> Switches depend on the load. I use standard 10A ac switches for most
> lights. Hell,a 10 amp ac switch running less than an amp dc is not a
> problem.

I was also thinking that a standard 10A ac switch would do the job.
I doubt that arcing would be a problem.
[color=darkred]
>
> Yes and white works fine or colour of your choice
>
> All my lighting is ELV @ 12V. I rework standard light fittings to run;
>
> LED lights, single LEDs or 18 LED lamps depending on use.
>
> QH globes.
>
> Dichroic Lamps.
>
> Standard fluros with dedicated inverters.
>
> All run with off the shelf fittings used in new ways.
>
> I have used:
>
> Rubber grommets as led bezels.

Not a bad idea. I'd consider it.

>
> Here we have a fitting which allows you to drop a lamp from a ceiling
> fitting. Magic, I just fit resistor and led into this and screw it into
> the fixture.
>
> PVC pipe to make lamps.
>
> The tops of spray paint cans as reflectors for QH bulbs. Use flat white
> paint for your reflectors, better than gloss white or silver.
>
> You should get a fittings catalogue from electrical wholesale supplier to
> the trade.
>
> While you have the framing exposed is the best time to do your lighting.
>
> I put up all my lighting at that stage. Some I moved 2 or 3 times to get
> them in the right spot. I used a lot of lights. I have 15 in the kitchen
> /dining alone. A mixture of QH, Dichroic and LED. They are placed for best
> effect over work spaces.
>

I am mainly focused here on night lights, meaning a few low intensity lights
spaced to aid in
navigtation. For my more general lighting needs, I use 115v compact
flourecents, and standard 115vac fixtures.

> The standard is a 60 or 100 watt lamp in the middle of a room. Dead loss.
>

Agreed. I use no incandecents at all. Typically, I will have no more than 3
CFL's on at a time.

> Non of my lamps exceeds 20(Fluros) watts and most are either 5W(QH) or
> 10W(QH and Dichroic) And three, 18 LED lamps over the breakfast bar.
>
>

I am planning on a breakfast bar. Several nice looking recessed fixtures
would be cool. That might be a good candidate for some multiple white led
lights instead of CFL's.

wmbjk

2005-12-16, 12:21 pm

On Fri, 16 Dec 2005 13:23:14 GMT, "Bughunter" <nobody@home.net> wrote:

>The recent discussion about LED lighting included a couple comments on the
>appropriateness of LEDS for night lights.

We don't have any night lights and have never felt the need for any.
If the route to the bathroom is perilous, you could add switches near
the bed to turn on a distant light sufficient to show the way. Or put
a small flashlight on a table next to the bed. As for the occasional
roam around the house at night without waking others, I find that the
twinkle of LEDs on miscellaneous appliances provides orientation. ;-)

Wayne

Ecnerwal

2005-12-16, 12:21 pm

The "right" way to run LEDs off a high voltage supply (right being
efficient) is to set up a constant current supply, since that is
"really" what LEDs need, not any specific voltage, so much. The number
of LEDs that can be in a single string is then limited by the voltage.
ie, one constant current supply run from 12 V can run X LEDs (often 8-10
of the usual sort of LEDs), and a similar one run from 48V can run 4X
LEDs, more or less. They will use exactly the same amount of energy to
run 1 LED, or as many LEDs as they can run, so maximizing LEDs per
supply is the most efficient approach.

The various LEDs run from one supply need not be in the same place, they
can be connected by wire and be in different locations. One supply might
run your entire nightlight setup throughout the house. The switch used
does need to be DC rated, and the circuit needs to be fused or have a
circuit breaker.

I'd go with red, as highly efficient red LEDs are available, and red
does not destroy your night vision, if you are getting up to view the
stars, or peer out to see if there's a burglar, or that sort of thing.

48V bank is too high for the usual part I use for making a constant
current supply (LM317 variable voltage regulator, set up as a constant
current supply per the application data). You could either use a DC-DC
down-converter, or (better) a different part or parts to achieve the
same result without the complexity, expense, and potential failure point
of the converter.

Specific current will depend on the LEDs, generally 10-30 mA (lower will
just be dimmer, too high will fry them). One mounting I've considered,
but not built yet, is in the underside of the stair handrail, routing a
groove to have a set pointing down to light the stairs. Invisible, and
thus does not "look" homemade or otherwise. A similar thing could be
done in rooms/hallways with moulding, our you could adapt various types
of light fixtures, but most seem overly large for the purpose. If
mounting into a switchplate, mount pointing down, I'd think. Some panel
lights (in the control or audio industry) or old style dashboard lights
(or even new-style license-plate lights) provide a nice-looking
partly-sheilded enclosure. But you might think of those as looking like
car parts in your house, and therefore "not nice" or "home-made".

--
Cats, coffee, chocolate...vices to live by

Kent Hoult

2005-12-16, 12:21 pm

If you use a string of LEDs to get the sum of the forward drop up to a few
volts below
the lowest battery voltage, then you can use one of many linear current
sources to drop
the voltage to run that string.

The Supertex CL2 is about the simplist possible. You leave at least a 5V
drop, put this
2 pin device in series with the LEDs, and you get a constant 20 mA through
them.
Whether you use 1 to ~11 white LEDs it will draw the same power (~1W). Put
a
switch in the circuit for On/Off control.

If you want fewer LEDs in a string, and are want lower power drain, then a
switching
LED driver is the way to go. With these it will use about 10% more than what
it actually
takes to run the LEDs, but waste a lot less in the regulator itself. The
Supertex HV9921
is a 3 pin switching controller that could run 1 to ~10 white LEDs. You will
need to add
a few extra parts to make this run (inductor, diode, cap).

Note: If you use other LED colors, you probably can have more in a string
since the forward
drop is lower.

Both of these parts easily handle the voltages from the battery pack since
they were designed
to hook to fullwave rectified 120VAC.

-Kent-

"Bughunter" <nobody@home.net> wrote in message
news:6dzof.4999$tR6.4796@trndny09...
> The recent discussion about LED lighting included a couple comments on the
> appropriateness of LEDS for night lights. I thought it was an idea worthy
> of it's own thread.
>
> My off grid home is in the stage of construction where the interior walls
> are still open accessible to add wiring runs. So, now is an opportune time
> for me to add wiring to the whole house. So far, I have not installed any
> low voltage wiring runs, just the 115vac wring typical of a standard US
> home.
>
> I have been casually thinking about adding a dedicated low voltage DC
> circuit to support some LED night lights as a simple aid to night
> navigation. I have a few ideas, but have not made any decisions yet. Maybe
> I can get some ideas here to influence me in one direction or another.
>
> I'm interested in ideas on how I might set up LED night lights throughout
> the house.
> Right now, I use a few glass enclosed tea candles for night lights which
> is romantic, but a little too 19th century. I want something that looks
> professional, and not homemade.
>
> My inverter runs in sleep mode at night, so I'd prefer a solution that
> does not require 115vac except perhaps for periodic (and hopefully
> infrequent) manual battery recharging.
>
> I wonder if it would make sense to power the LED night lights from my main
> 48v battery bank, or to use a separate dedicated bank, and maybe at a
> different voltage?
>
> My main bank runs at 48v. I suppose it would be easy enough to run a
> dedicated, fused, 48v wiring run..With a 48v run, I would not have as much
> voltage drop across the wire and could use smaller gauge wire. But, would
> I be just burning it off in resistors required to drop the voltage to that
> required by the LEDs?
>
> Alternatively, I could setup a separate 6v (or 12v) deep cycle golf cart
> battery. This would require periodic recharging, probably with an
> inexpensive automotive charger plugged into my 110vac. I'd almost prefer
> not to go this route, because it adds one more thing separate subsystem to
> have to monitor and maintain. On the other hand, if it were 12v, then I
> might find it useful for other non-nightlight applications such as
> recharging my cell phone where 12v is the more common voltage. DC to DC
> converters are somewhat pricey, but I suppose for one or two low draw
> outlets it is a possibility.
>
> I am thinking that a single switch per floor would be adequate for my
> place. I wonder if I could just use a normal 110vac light switch for
> 48VDC, or I would need a DC rated switch?
>
> It would be nice if I could use some small gauge wire, like Cat5, or door
> bell wire. Each wire run might be in the range of 100 feet per floor.
>
> My place is 2200 square feet, on two floors. I think 6 to 8 night-lights
> fixtures per floor would provide adequate night lighting.
>
> Is a single led per fixture adequate? Color?
>
> Are there any off the shelf low voltage DC fixtures that might be
> applicable. I don't want to reinvent the wheel if an off the shelf
> solution exists, as long as it is no too expensive.
>
> I wonder what kind of fixture could be made that would be simple to
> construct, yet
> not look homemade. One thought is to use a single outlet type mounting
> box, and use a blank switch plate mount a led. Maybe more than one led per
> plate?
>
> Ideas? Experiences? Links? Calculations?
>
>
>

Steve Spence

2005-12-16, 12:21 pm

wmbjk wrote:
> On Fri, 16 Dec 2005 13:23:14 GMT, "Bughunter" <nobody@home.net> wrote:
>
>
>
>
> We don't have any night lights and have never felt the need for any.
> If the route to the bathroom is perilous, you could add switches near
> the bed to turn on a distant light sufficient to show the way. Or put
> a small flashlight on a table next to the bed. As for the occasional
> roam around the house at night without waking others, I find that the
> twinkle of LEDs on miscellaneous appliances provides orientation. ;-)
>
> Wayne

Our LED lit appliances are shut off at night, so a few LED nightlights
keep the kids from falling down the stairs or tripping over the dog at
night.

$2 for the nightlight, and my KAW can't even measure the kWh used in a
24 hour period.

--
Steve Spence
Dir., Green Trust, http://www.green-trust.org
Contributing Editor, http://www.off-grid.net
http://www.rebelwolf.com/essn.html

GeekBoy

2005-12-16, 1:21 pm

You do not need low voltage wiring.

Your local WalMart sells LED night lights that plug into regular outlets.

They also sell those even more effecient lights that use the same Timex
Indiglow technology. The package says uses only pennies a year in
electricity.

"Bughunter" <nobody@home.net> wrote in message
news:6dzof.4999$tR6.4796@trndny09...
> The recent discussion about LED lighting included a couple comments on the
> appropriateness of LEDS for night lights. I thought it was an idea worthy
> of it's own thread.
>
> My off grid home is in the stage of construction where the interior walls
> are still open accessible to add wiring runs. So, now is an opportune time
> for me to add wiring to the whole house. So far, I have not installed any
> low voltage wiring runs, just the 115vac wring typical of a standard US
> home.
>
> I have been casually thinking about adding a dedicated low voltage DC
> circuit to support some LED night lights as a simple aid to night
> navigation. I have a few ideas, but have not made any decisions yet. Maybe
> I can get some ideas here to influence me in one direction or another.
>
> I'm interested in ideas on how I might set up LED night lights throughout
> the house.
> Right now, I use a few glass enclosed tea candles for night lights which
> is romantic, but a little too 19th century. I want something that looks
> professional, and not homemade.
>
> My inverter runs in sleep mode at night, so I'd prefer a solution that
> does not require 115vac except perhaps for periodic (and hopefully
> infrequent) manual battery recharging.
>
> I wonder if it would make sense to power the LED night lights from my main
> 48v battery bank, or to use a separate dedicated bank, and maybe at a
> different voltage?
>
> My main bank runs at 48v. I suppose it would be easy enough to run a
> dedicated, fused, 48v wiring run..With a 48v run, I would not have as much
> voltage drop across the wire and could use smaller gauge wire. But, would
> I be just burning it off in resistors required to drop the voltage to that
> required by the LEDs?
>
> Alternatively, I could setup a separate 6v (or 12v) deep cycle golf cart
> battery. This would require periodic recharging, probably with an
> inexpensive automotive charger plugged into my 110vac. I'd almost prefer
> not to go this route, because it adds one more thing separate subsystem to
> have to monitor and maintain. On the other hand, if it were 12v, then I
> might find it useful for other non-nightlight applications such as
> recharging my cell phone where 12v is the more common voltage. DC to DC
> converters are somewhat pricey, but I suppose for one or two low draw
> outlets it is a possibility.
>
> I am thinking that a single switch per floor would be adequate for my
> place. I wonder if I could just use a normal 110vac light switch for
> 48VDC, or I would need a DC rated switch?
>
> It would be nice if I could use some small gauge wire, like Cat5, or door
> bell wire. Each wire run might be in the range of 100 feet per floor.
>
> My place is 2200 square feet, on two floors. I think 6 to 8 night-lights
> fixtures per floor would provide adequate night lighting.
>
> Is a single led per fixture adequate? Color?
>
> Are there any off the shelf low voltage DC fixtures that might be
> applicable. I don't want to reinvent the wheel if an off the shelf
> solution exists, as long as it is no too expensive.
>
> I wonder what kind of fixture could be made that would be simple to
> construct, yet
> not look homemade. One thought is to use a single outlet type mounting
> box, and use a blank switch plate mount a led. Maybe more than one led per
> plate?
>
> Ideas? Experiences? Links? Calculations?
>
>
>

Steve Spence

2005-12-16, 1:21 pm

GeekBoy wrote:[color=darkred]
> You do not need low voltage wiring.
>
> Your local WalMart sells LED night lights that plug into regular outlets.
>
> They also sell those even more effecient lights that use the same Timex
> Indiglow technology. The package says uses only pennies a year in
> electricity.
>
>
> "Bughunter" <nobody@home.net> wrote in message
> news:6dzof.4999$tR6.4796@trndny09...
>

You missed the part not wanting to wake up the inverter .....

--
Steve Spence
Dir., Green Trust, http://www.green-trust.org
Contributing Editor, http://www.off-grid.net
http://www.rebelwolf.com/essn.html

Dale Farmer

2005-12-16, 1:21 pm

GeekBoy

2005-12-16, 1:21 pm

"Steve Spence" <sspence@green-trust.org> wrote in message
news:43a2f07b_5@newsfeed.slurp.net...
> GeekBoy wrote:
>
> You missed the part not wanting to wake up the inverter .....

Battery night lights?

>
>
> --
> Steve Spence
> Dir., Green Trust, http://www.green-trust.org
> Contributing Editor, http://www.off-grid.net
> http://www.rebelwolf.com/essn.html

SQLit

2005-12-16, 2:21 pm

"Bughunter" <nobody@home.net> wrote in message
news:6dzof.4999$tR6.4796@trndny09...
> The recent discussion about LED lighting included a couple comments on the
> appropriateness of LEDS for night lights. I thought it was an idea worthy
of
> it's own thread.
>
> My off grid home is in the stage of construction where the interior walls
> are still open accessible to add wiring runs. So, now is an opportune time
> for me to add wiring to the whole house. So far, I have not installed any
> low voltage wiring runs, just the 115vac wring typical of a standard US
> home.
>
> I have been casually thinking about adding a dedicated low voltage DC
> circuit to support some LED night lights as a simple aid to night
> navigation. I have a few ideas, but have not made any decisions yet. Maybe
I
> can get some ideas here to influence me in one direction or another.
>
> I'm interested in ideas on how I might set up LED night lights throughout
> the house.
> Right now, I use a few glass enclosed tea candles for night lights which
is
> romantic, but a little too 19th century. I want something that looks
> professional, and not homemade.
>
> My inverter runs in sleep mode at night, so I'd prefer a solution that
does
> not require 115vac except perhaps for periodic (and hopefully infrequent)
> manual battery recharging.
>
> I wonder if it would make sense to power the LED night lights from my main
> 48v battery bank, or to use a separate dedicated bank, and maybe at a
> different voltage?
>
> My main bank runs at 48v. I suppose it would be easy enough to run a
> dedicated, fused, 48v wiring run..With a 48v run, I would not have as much
> voltage drop across the wire and could use smaller gauge wire. But, would
I
> be just burning it off in resistors required to drop the voltage to that
> required by the LEDs?
>
> Alternatively, I could setup a separate 6v (or 12v) deep cycle golf cart
> battery. This would require periodic recharging, probably with an
> inexpensive automotive charger plugged into my 110vac. I'd almost prefer
not
> to go this route, because it adds one more thing separate subsystem to
have
> to monitor and maintain. On the other hand, if it were 12v, then I might
> find it useful for other non-nightlight applications such as recharging my
> cell phone where 12v is the more common voltage. DC to DC converters are
> somewhat pricey, but I suppose for one or two low draw outlets it is a
> possibility.
>
> I am thinking that a single switch per floor would be adequate for my
place.
> I wonder if I could just use a normal 110vac light switch for 48VDC, or I
> would need a DC rated switch?
>
> It would be nice if I could use some small gauge wire, like Cat5, or door
> bell wire. Each wire run might be in the range of 100 feet per floor.
>
> My place is 2200 square feet, on two floors. I think 6 to 8 night-lights
> fixtures per floor would provide adequate night lighting.
>
> Is a single led per fixture adequate? Color?
>
> Are there any off the shelf low voltage DC fixtures that might be
> applicable. I don't want to reinvent the wheel if an off the shelf
solution
> exists, as long as it is no too expensive.
>
> I wonder what kind of fixture could be made that would be simple to
> construct, yet
> not look homemade. One thought is to use a single outlet type mounting
box,
> and use a blank switch plate mount a led. Maybe more than one led per
plate?
>
> Ideas? Experiences? Links? Calculations?

I did a medical clinic in CA once that required a set of exit signs 12
inches off the floor. I am not advocating the exit signs but the location
close to the doors was actually a good plan. In complete darkness, em
fixtures off, the inspector walked the building from 30-40 feet away the
exit was clear.

I would try to keep it simple, standard voltage, standard parts, etc. Walk
way light cans might be an idea.You know with the lovered covers. I used
them around a guys pool once. Nice soft light I used 25 watt bulbs, CF's
were a long way off then. Mounted the fixtures at 12" to bottom. I had a
bunch of dimmers in a closet and put the switches for the walk lights in
there. I connected them to a photocell circuit so that they turned on
automatically. Since your not using 120v like I was the photo control might
be a little harder.

I would use larger than smaller wire if the choice was given, at least #12,
stranded would be better for 12v. I am not aware of stranded wire that is
available in a romex type cable. Not sure if the lv outside cable can be
installed in a wall, by code. Better check the listing on that one.

http://www.sonriselighting.com/docs...rstepindex.html
similar to these only not brass.
http://www.gidesigns.net/bfocus.html

Bughunter

2005-12-16, 2:21 pm

"Ecnerwal" <LawrenceSMITH@SOuthernVERmont.NyET> wrote in message
news:LawrenceSMITH-A1099D.10514616122005@news.verizon.net...
> The "right" way to run LEDs off a high voltage supply (right being
> efficient) is to set up a constant current supply, since that is
> "really" what LEDs need, not any specific voltage, so much. The number
> of LEDs that can be in a single string is then limited by the voltage.
> ie, one constant current supply run from 12 V can run X LEDs (often 8-10
> of the usual sort of LEDs), and a similar one run from 48V can run 4X
> LEDs, more or less. They will use exactly the same amount of energy to
> run 1 LED, or as many LEDs as they can run, so maximizing LEDs per
> supply is the most efficient approach.
>
> The various LEDs run from one supply need not be in the same place, they
> can be connected by wire and be in different locations. One supply might
> run your entire nightlight setup throughout the house. The switch used
> does need to be DC rated, and the circuit needs to be fused or have a
> circuit breaker.
>
> I'd go with red, as highly efficient red LEDs are available, and red
> does not destroy your night vision, if you are getting up to view the
> stars, or peer out to see if there's a burglar, or that sort of thing.
>
> 48V bank is too high for the usual part I use for making a constant
> current supply (LM317 variable voltage regulator, set up as a constant
> current supply per the application data). You could either use a DC-DC
> down-converter, or (better) a different part or parts to achieve the
> same result without the complexity, expense, and potential failure point
> of the converter.
>
> Specific current will depend on the LEDs, generally 10-30 mA (lower will
> just be dimmer, too high will fry them). One mounting I've considered,
> but not built yet, is in the underside of the stair handrail, routing a
> groove to have a set pointing down to light the stairs. Invisible, and
> thus does not "look" homemade or otherwise. A similar thing could be
> done in rooms/hallways with moulding, our you could adapt various types
> of light fixtures, but most seem overly large for the purpose. If
> mounting into a switchplate, mount pointing down, I'd think. Some panel
> lights (in the control or audio industry) or old style dashboard lights
> (or even new-style license-plate lights) provide a nice-looking
> partly-sheilded enclosure. But you might think of those as looking like
> car parts in your house, and therefore "not nice" or "home-made".
>
> --
> Cats, coffee, chocolate...vices to live by

Excellent feedback. I'll have to research constant current supplies.

At this point haven't decided on color or specs for leds. I presume that
would be one factor I'd have to get nailed down before I tried to make the
decision on what type of supply would work.

It started out seeming like a simple enough project, and then you discover
how many decisions there are to be made, number of fixtures, how many leds,
type of supply, type of mounting, color, esthetics, efficiency....

Steve Spence

2005-12-16, 2:21 pm

Xref: number1.nntp.dca.giganews.com alt.energy.homepower:121791

GeekBoy wrote:
> "Steve Spence" <sspence@green-trust.org> wrote in message
> news:43a2f07b_5@newsfeed.slurp.net...
>
>
>
> Battery night lights?
>
>
>
>
>
>

That would work if it had a light sensor on it to shut it off during the
day. I have an ac nightlight with that function.

--
Steve Spence
Dir., Green Trust, http://www.green-trust.org
Contributing Editor, http://www.off-grid.net
http://www.rebelwolf.com/essn.html

Bughunter

2005-12-16, 3:21 pm

"SQLit" <sqlit@qwest.net> wrote in message
news:oVCof.20$jy3.5062@news.uswest.net...
>
> "Bughunter" <nobody@home.net> wrote in message
> news:6dzof.4999$tR6.4796@trndny09...
> of
> I
> is
> does
> I
> not
> have
> place.
> solution
> box,
> plate?
>
> I did a medical clinic in CA once that required a set of exit signs 12
> inches off the floor. I am not advocating the exit signs but the location
> close to the doors was actually a good plan. In complete darkness, em
> fixtures off, the inspector walked the building from 30-40 feet away the
> exit was clear.
>
> I would try to keep it simple, standard voltage, standard parts, etc. Walk
> way light cans might be an idea.You know with the lovered covers. I used
> them around a guys pool once. Nice soft light I used 25 watt bulbs, CF's
> were a long way off then. Mounted the fixtures at 12" to bottom. I had a
> bunch of dimmers in a closet and put the switches for the walk lights in
> there. I connected them to a photocell circuit so that they turned on
> automatically. Since your not using 120v like I was the photo control
> might
> be a little harder.
>
> I would use larger than smaller wire if the choice was given, at least
> #12,
> stranded would be better for 12v. I am not aware of stranded wire that is
> available in a romex type cable. Not sure if the lv outside cable can be
> installed in a wall, by code. Better check the listing on that one.
>
>
> http://www.sonriselighting.com/docs...rstepindex.html
> similar to these only not brass.
> http://www.gidesigns.net/bfocus.html
>
>

For my purposes, something low to the floor would work best. We have several
traditional night lights that plug into outlets (~15 inches above the floor)
at my on-grid home. I navigate through the house without ever turning on a
light. It is something you get used to having. I miss it on my off grid
home. I don't want to keep the inverter running just to power a few night
lights.

I do have a current NEC code book. I will consult that before I start
drilling holes and running wire.

I am trying to keep it simple, with mostly off the shelf parts. The search
continues.

fcrumpler@cityofsunrise.org

2005-12-16, 4:21 pm

Someone mentioned those flat plate nitelights that use Timex Indiglo
technology. Does anyone know what voltage the actual device uses? I
know that they plug into a 120V socket, but could it be run from DC?

vaughnsimon@att.net

2005-12-16, 4:21 pm

What you are describing is a (or at least could be) low-energy circuit
that could be incorporated into the same raceways and boxes with your
other low voltage wiring such as CATV, phone, speaker, and network.
With a little clever design, you could incorporate the nightlight right
into the faceplace of terminal boxes that you were going to need
anyhow. With a little punchblock, you could series-connect perhaps 4
lights in a string and feed them with (what?) 50 miliamps? In the case
that one LED went bad, trouble shooting would be simple. You can get
any number of small DC-DC converters cheap at MPJA.com to convert your
48 volts down to something more efficient.

Steve Spence

2005-12-16, 5:21 pm

fcrumpler@cityofsunrise.org wrote:
> Someone mentioned those flat plate nitelights that use Timex Indiglo
> technology. Does anyone know what voltage the actual device uses? I
> know that they plug into a 120V socket, but could it be run from DC?
>

They require 120vac. We lost 4 of them before switching to LED nightlights.

--
Steve Spence
Dir., Green Trust, http://www.green-trust.org
Contributing Editor, http://www.off-grid.net
http://www.rebelwolf.com/essn.html

daestrom

2005-12-16, 5:21 pm

"Kent Hoult" <khoult@cisco.com> wrote in message
news:1134749702.576280@sj-nntpcache-3...
> If you use a string of LEDs to get the sum of the forward drop up to a few
> volts below
> the lowest battery voltage, then you can use one of many linear current
> sources to drop
> the voltage to run that string.
>
> The Supertex CL2 is about the simplist possible. You leave at least a 5V
> drop, put this
> 2 pin device in series with the LEDs, and you get a constant 20 mA through
> them.
> Whether you use 1 to ~11 white LEDs it will draw the same power (~1W). Put
> a
> switch in the circuit for On/Off control.
>

The only thing with linear current sources, is the constant current x the
constant voltage drop leads to a lot of energy wasted as heat.

I ran a cross a simple 'switching' circuit somewhere, that feeds the LED's
through a choke, and switches off, letting them 'free-wheel' through a
reverse diode when the current rises to the setpoint. Then turns on again
after a miniscule off-time. If I can find the circuit again, I'll post a
link.

Switching like this, if the extra circuits don't draw too much, can be much
more efficient way of regulating the current.

daestrom

Kent Hoult

2005-12-16, 6:21 pm

Doesn't that really depend on your drop across the linear reg. If you get
the drop to 5 volts on a 50 volt supply, that's 90% efficient. Pretty much
the
same as switching supply.

The real feature of the CL2 is it simplicity. You don't need any caps,
resistors, etc.
You probably don't even need a circuit board. Solder it inline and
heat-shink tube it.

I agree, if you don't want to use enough LEDs to get up to the good
efficiency point, and
you really care about that level of waste (fraction of a watt per string),
then a switcher is the
way to go. The one I mentioned in the preveious post (Supertex HV9921) has
the feature
of being about the simplist possible buck switcher chip since it is
configured to be a 20mA current
source just for running LEDs, and it handles a high voltage input. It sounds
like it is exactly the
circuit you were describing.

-Kent-

"daestrom" <daestrom@NO_SPAM_HEREtwcny.rr.com> wrote in message
news:F7Gof.31596$XJ5.6704@twister.nyroc.rr.com...
>
> "Kent Hoult" <khoult@cisco.com> wrote in message
> news:1134749702.576280@sj-nntpcache-3...
>
> The only thing with linear current sources, is the constant current x the
> constant voltage drop leads to a lot of energy wasted as heat.
>
> I ran a cross a simple 'switching' circuit somewhere, that feeds the LED's
> through a choke, and switches off, letting them 'free-wheel' through a
> reverse diode when the current rises to the setpoint. Then turns on again
> after a miniscule off-time. If I can find the circuit again, I'll post a
> link.
>
> Switching like this, if the extra circuits don't draw too much, can be
> much more efficient way of regulating the current.
>
> daestrom
>
>

Bughunter

2005-12-16, 6:21 pm

<vaughnsimon@att.net> wrote in message
news:1134763694.859756.94610@z14g2000cwz.googlegroups.com...
> What you are describing is a (or at least could be) low-energy circuit
> that could be incorporated into the same raceways and boxes with your
> other low voltage wiring such as CATV, phone, speaker, and network.
> With a little clever design, you could incorporate the nightlight right
> into the faceplace of terminal boxes that you were going to need
> anyhow. With a little punchblock, you could series-connect perhaps 4
> lights in a string and feed them with (what?) 50 miliamps? In the case
> that one LED went bad, trouble shooting would be simple. You can get
> any number of small DC-DC converters cheap at MPJA.com to convert your
> 48 volts down to something more efficient.
>

Thanks for mentioning MPJA.com. I knew I had seen some relatively
inexpensive dc-dc converters some place.
http://mpja.com/productview.asp?product=7724+PS is way overkill and a bit
pricey at $60. They also have one for $25, but it requires +5v to activate
it. I'll bet there is an even lower power rated converter out there for a
lot less. Like you say, we are talking about a load in milliamps even for
an entire string of lights. I think that a cheap low power dc-dc converter
of some type is in order in any case if I am to use my main 48v battery bank
as the source, which is my preference. I might leave these night-lights on
year round, even when I am not there.

I did some very brief research into Ecnerwal's suggestion about a constant
current supply. This does seem to be the way the pros do it in contemporary
product design. I have to admit that my electronics is a bit rusty and I
have few resources to design like a pro. I will need to fins some rather
simple pre-packaged items to cobble together, of the simplest of circuits
with a handful of very easy to obtain parts. It makes me feel foolish to
contact an electronic manufacturer parts salesman, and ask for 6 widgets
when real engineers are ordering tens of thousands at a whack. I'm
comfortable with a low volume surplus supplier like MPJA, but their
selection is limited.

I am not sure how much cat5 I'll run if any at all. I am using wireless for
most of my network at home. I might run some lines for satellite TV. But, I
do think it is within code to run 48V along with communication lines.

Dale Farmer

2005-12-16, 7:21 pm

Steve Spence wrote:

> fcrumpler@cityofsunrise.org wrote:
>
> They require 120vac. We lost 4 of them before switching to LED nightlights.

There are also the cold cathode fluorescent stuff. Widely used for
making your car very flashy and stupid looking. Available in different
colors and forms at Walmart, runs on 12 VDC. I have no idea
how efficient they are.

--Dale

Vaughn

2005-12-16, 8:21 pm

"Bughunter" <nobody@home.net> wrote in message news:QJGof.31$5h2.9@trndny02...
>
>But, I do think it is within code to run 48V along with communication lines.

I can't give you "chaper & verse" on code requirements, but I can tell you
that 48 volts has been a standard telephone talk voltage since the days of Alex
Bell. And don't forget that 105 VAC is still the standard ring voltage!

Vaughn

>
>
>
>
>
>
>
>
>
>

Bughunter

2005-12-16, 8:21 pm

The CL2 seems like a very cool device.It's dead nuts simple. I like the idea
of being able to solder in inline, with no board. I am not really too
worried about attaining maximum efficiency. If this is running at 1w that's
fine as long as I can get a few functional night lights out of it. That is a
whole lot more efficient than keeping my inverter running. My battery bank
would probably not even notice it.

Now I wonder what their salesman will tell me when I ask for 5 of em?

Some links I found in a very quick Google search are...

http://www10.edacafe.com/nbc/articl...rticleid=190475

and the data sheet at
http://www10.edacafe.com/nbc/articl...rticleid=190475

"Kent Hoult" <khoult@cisco.com> wrote in message
news:1134769207.394945@sj-nntpcache-3...
> Doesn't that really depend on your drop across the linear reg. If you get
> the drop to 5 volts on a 50 volt supply, that's 90% efficient. Pretty much
> the
> same as switching supply.
>
> The real feature of the CL2 is it simplicity. You don't need any caps,
> resistors, etc.
> You probably don't even need a circuit board. Solder it inline and
> heat-shink tube it.
>
> I agree, if you don't want to use enough LEDs to get up to the good
> efficiency point, and
> you really care about that level of waste (fraction of a watt per string),
> then a switcher is the
> way to go. The one I mentioned in the preveious post (Supertex HV9921) has
> the feature
> of being about the simplist possible buck switcher chip since it is
> configured to be a 20mA current
> source just for running LEDs, and it handles a high voltage input. It
> sounds like it is exactly the
> circuit you were describing.
>
> -Kent-
>
> "daestrom" <daestrom@NO_SPAM_HEREtwcny.rr.com> wrote in message
> news:F7Gof.31596$XJ5.6704@twister.nyroc.rr.com...
>
>

Bughunter

2005-12-16, 9:21 pm

Yup, 48v seems to be am old telecom standard. An electrician friend gave me
his old copy of the NEC code book. I can always dig into that, but I'm sure
you are correct.

"Vaughn" <vaughnsimonHATESSPAM@att.fake.net> wrote in message
news:n0Iof.162607$qk4.112850@bgtnsc05-news.ops.worldnet.att.net...
>
> "Bughunter" <nobody@home.net> wrote in message
> news:QJGof.31$5h2.9@trndny02...
>
> I can't give you "chaper & verse" on code requirements, but I can tell
> you that 48 volts has been a standard telephone talk voltage since the
> days of Alex Bell. And don't forget that 105 VAC is still the standard
> ring voltage!
>
> Vaughn
>
>
>
>

Duane C. Johnson

2005-12-16, 11:21 pm

Hi Bug;

Bughunter <nobody@home.net> wrote:

> I wonder if it would make sense to power the LED night
> lights from my main 48v battery bank, or to use a
> separate dedicated bank, and maybe at a different voltage?

> My main bank runs at 48v. I suppose it would be easy
> enough to run a dedicated, fused, 48v wiring run..
> With a 48v run, I would not have as much voltage drop
> across the wire and could use smaller gauge wire.

This is technically true.
However, as a practical mater this is irrelevant. The
currents for a 12V system are quite low. The wire size
from the "tables" would be to small to conveniently use.

> But, would I be just burning it off in resistors required
> to drop the voltage to that required by the LEDs?

Not really. You would design it so there were several
LEDs in series. A 12V system would have 1/4th the number
of LEDs in each string as in the 48V string.

The loss in the ballast can be the same in either case.

> Alternatively, I could setup a separate 6v (or 12v)
> deep cycle golf cart battery. This would require periodic
> recharging, probably with an inexpensive automotive
> charger plugged into my 110vac. I'd almost prefer not
> to go this route, because it adds one more thing separate
> subsystem to have to monitor and maintain.

> On the other hand, if it were 12v, then I might find it
> useful for other non-nightlight applications such as
> recharging my cell phone where 12v is the more common
> voltage. DC to DC converters are somewhat pricey, but I
> suppose for one or two low draw outlets it is a
> possibility.

> I am thinking that a single switch per floor would be
> adequate for my place. I wonder if I could just use a
> normal 110vac light switch for 48VDC, or I would need
> a DC rated switch?

It is definitely not cool to use AC wall switches on DC.
The problem is the arcing that can happen when opening
the "AC" switch.

I have done a bunch of experimenting on how to adapt the
"AC" switches for use in DC systems. See:
http://www.redrok.com/misc1.htm#dcswitch

Duane

--
Home of the $35 Solar Tracker Receiver
http://www.redrok.com/led3xassm.htm [*]
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JoeSP

2005-12-16, 11:21 pm

"Bughunter" <nobody@home.net> wrote in message
news:6dzof.4999$tR6.4796@trndny09...
> The recent discussion about LED lighting included a couple comments on the
> appropriateness of LEDS for night lights. I thought it was an idea worthy
> of it's own thread.
>
> My off grid home is in the stage of construction where the interior walls
> are still open accessible to add wiring runs. So, now is an opportune time
> for me to add wiring to the whole house. So far, I have not installed any
> low voltage wiring runs, just the 115vac wring typical of a standard US
> home.
>
> I have been casually thinking about adding a dedicated low voltage DC
> circuit to support some LED night lights as a simple aid to night
> navigation. I have a few ideas, but have not made any decisions yet. Maybe
> I can get some ideas here to influence me in one direction or another.
>
> I'm interested in ideas on how I might set up LED night lights throughout
> the house.
> Right now, I use a few glass enclosed tea candles for night lights which
> is romantic, but a little too 19th century. I want something that looks
> professional, and not homemade.
>
> My inverter runs in sleep mode at night, so I'd prefer a solution that
> does not require 115vac except perhaps for periodic (and hopefully
> infrequent) manual battery recharging.
>
> I wonder if it would make sense to power the LED night lights from my main
> 48v battery bank, or to use a separate dedicated bank, and maybe at a
> different voltage?
>
> My main bank runs at 48v. I suppose it would be easy enough to run a
> dedicated, fused, 48v wiring run..With a 48v run, I would not have as much
> voltage drop across the wire and could use smaller gauge wire. But, would
> I be just burning it off in resistors required to drop the voltage to that
> required by the LEDs?
>
> Alternatively, I could setup a separate 6v (or 12v) deep cycle golf cart
> battery. This would require periodic recharging, probably with an
> inexpensive automotive charger plugged into my 110vac. I'd almost prefer
> not to go this route, because it adds one more thing separate subsystem to
> have to monitor and maintain. On the other hand, if it were 12v, then I
> might find it useful for other non-nightlight applications such as
> recharging my cell phone where 12v is the more common voltage. DC to DC
> converters are somewhat pricey, but I suppose for one or two low draw
> outlets it is a possibility.
>
> I am thinking that a single switch per floor would be adequate for my
> place. I wonder if I could just use a normal 110vac light switch for
> 48VDC, or I would need a DC rated switch?
>
> It would be nice if I could use some small gauge wire, like Cat5, or door
> bell wire. Each wire run might be in the range of 100 feet per floor.
>
> My place is 2200 square feet, on two floors. I think 6 to 8 night-lights
> fixtures per floor would provide adequate night lighting.
>
> Is a single led per fixture adequate? Color?
>
> Are there any off the shelf low voltage DC fixtures that might be
> applicable. I don't want to reinvent the wheel if an off the shelf
> solution exists, as long as it is no too expensive.
>
> I wonder what kind of fixture could be made that would be simple to
> construct, yet
> not look homemade. One thought is to use a single outlet type mounting
> box, and use a blank switch plate mount a led. Maybe more than one led per
> plate?
>
> Ideas? Experiences? Links? Calculations?

LED house lighting is still in its infancy. It may turn out to be a big
mistake to commit to one type of wiring at this stage. We do not know which
formats will emerge as those that stay. I suggest running wires that allow
for flexibility in voltages. The fixtures can be changed over the years, but
the wiring is a different story. Stick to the minimum specs required for a
wide range of options.

By the very nature of white LED lighting, we know that there is much room
for improved efficiency and the ability to tune the wavelengths by altering
the mix of red, blue and green. Tomorrow's dimmer switch may not only allow
us to lower the light level, but to adjust the colors, shades and hues of
the room lighting as well. Stay tuned.

Steve Spence

2005-12-16, 11:21 pm

Dale Farmer wrote:
>
> Steve Spence wrote:
>
>
>
>
> There are also the cold cathode fluorescent stuff. Widely used for
> making your car very flashy and stupid looking. Available in different
> colors and forms at Walmart, runs on 12 VDC. I have no idea
> how efficient they are.
>
> --Dale
>
>

Pretty efficient.

--
Steve Spence
Dir., Green Trust, http://www.green-trust.org
Contributing Editor, http://www.off-grid.net
http://www.rebelwolf.com/essn.html

Antipodean Bucket Farmer

2005-12-17, 12:21 am

In article
<t4n5q1dvm6o21h4uovari1ajj6066ujun4@4ax.com>,
wmbjkREMOVE@citlink.net says...
> On Fri, 16 Dec 2005 13:23:14 GMT, "Bughunter" <nobody@home.net> wrote:
>
>
> We don't have any night lights and have never felt the need for any.
> If the route to the bathroom is perilous, you could add switches near
> the bed to turn on a distant light sufficient to show the way. Or put
> a small flashlight on a table next to the bed. As for the occasional
> roam around the house at night without waking others, I find that the
> twinkle of LEDs on miscellaneous appliances provides orientation. ;-)

I use a battery-powered (4 x AA plus an input for 6v
from a wall wart, etc) light with a motion detector.
Switchable to light either a regular torch type bulb,
or a circle of white LEDs. It is in the hallway
between the bedroom and bathroom. Can be turned on at
night and off in the morning.

NZ$25 from The Warehouse (equivalent to Wal-Mart.)
Seems that one might be DIY-built at slightly lower
cost, with one of those motion sensors sold for modular
burglar alarm systems.

Also good in case of a power outage.

Another idea would be wireless remote control next to
the bed, to avoid installation of wired switches (e.g.
in a rented apartment.)

--
Get Credit Where Credit Is Due
http://www.cardreport.com/
Credit Tools, Reference, and Forum

George Ghio

2005-12-17, 12:21 am

Bughunter wrote:
> "George Ghio" <AKA@nomailhere.com> wrote in message
> news:43a2cfbd_3@news.chariot.net.au...
>
>
> But, I don't think I'd need 16 LEDs for a single night-light. I'm thinking
> that 1-3 might be
> enough (light-wise) for each fixture. I don't think that I want to run
> series strings in the walls although it would be possible. It feels a little
> like those series strings of xmas lights, where you had to search for the
> bad bulb to fix a string. With the long life of LEDs, it would much less of
> a problem. Maybe it does make more sense to just use 16 leds and get more
> light rather than just disipating the power in resistors as heat.

Well I wouldn't do it, but it is a consideration if it might suit the
needs.

Then again, for a whole house night light, one at each end of a hall,
top and bottom of stairs...
>
>
>
> I was also thinking that a standard 10A ac switch would do the job.
> I doubt that arcing would be a problem.
>
>
>
>
> Not a bad idea. I'd consider it.
>
>
>
>
>
> I am mainly focused here on night lights, meaning a few low intensity lights
> spaced to aid in
> navigtation. For my more general lighting needs, I use 115v compact
> flourecents, and standard 115vac fixtures.
>
>
>
>
>
> Agreed. I use no incandecents at all. Typically, I will have no more than 3
> CFL's on at a time.
>
>
>
>
>
> I am planning on a breakfast bar. Several nice looking recessed fixtures
> would be cool. That might be a good candidate for some multiple white led
> lights instead of CFL's.
>
>

The best thing is to try your lights while you can still move them
around. I had lights in a bare frame for months. I would go and try them
at night, walk around, sit in a chair to read, whatever. Moved some of
the lights several times to get the right spot for the fixture.

Tried different types of lights in a number of places to see what worked
or in a number of cases what didn't before running the cable.

Ecnerwal

2005-12-17, 1:21 am

In article <43a322e4$1_5@newsfeed.slurp.net>,
Steve Spence <sspence@green-trust.org> wrote:

> fcrumpler@cityofsunrise.org wrote:
>
> They require 120vac. We lost 4 of them before switching to LED nightlights.

I have two dead flat plate lights here. Less than a year of useful life
- I think the material might be "fine" but the contact between the
material and the plug seems to be busted and not fixable - without any
particular abuse at all (ie, plugged in left alone - not repeatedly
plugged and unplugged or beaten on in any way - just stopped lighting
up. I have watches with 5 times that life on them that still light up.)

Don't waste your money on those...

--
Cats, coffee, chocolate...vices to live by

Ecnerwal

2005-12-17, 1:21 am

In article <XxIof.135$dh2.75@trndny08>, "Bughunter" <nobody@home.net>
wrote:
> Now I wonder what their salesman will tell me when I ask for 5 of em?

See if either

www.digikey.com

www.mouser.com

stock them - they are both happy to sell you one, 10, 100 or 10000 (at
different prices) of various things, though they might have a minimum
order (but not a large one, and easy enough if you put your shopping hat
on - grab some LEDs and switches, for instance).

OK, I looked - Mouser has them - $0.70 for 1, $0.52/ea for 1000.

Well, actually there seem to be several options among Supertex CL2,
probably related to package (ie, tiny surface mount or more useful to
normal humans leads), and I'm not looking into it in detail as I need to
get to sleep, but somewhere in that ballpark, and I'm not quickly
finding a minimum order amount, but have certainly placed small orders
there in the past, so it can't be too obnoxious.

--
Cats, coffee, chocolate...vices to live by

meow2222@care2.com

2005-12-17, 3:21 am

Bughunter wrote:

>The recent discussion about LED lighting included a couple comments on the
>appropriateness of LEDS for night lights. I thought it was an idea worthy =
of
>it's own thread.

>My off grid home is in the stage of construction where the interior walls
>are still open accessible to add wiring runs. So, now is an opportune time
>for me to add wiring to the whole house. So far, I have not installed any
>low voltage wiring runs, just the 115vac wring typical of a standard US
>home.

Do it. Now is the time to install a bundle of LV wiring for whaetevr
future uses come along. Lighting, alt power, zoned temp control,
security, data comms, remote control, and who knows what will become
useful in future. Running cat5 is very cheap, and it would be a lost
oportunity not to run it, even if you dont have a specific use right
now. Its very cheap to run it, and difficult to put in later. You'll
likely regret it if you dont.

2x or 3x Cat5 is good because its the leading standard and its
adaptable. Multicore burglar alarm wiring is also useful.

>I have been casually thinking about adding a dedicated low voltage DC
>circuit to support some LED night lights as a simple aid to night
>navigation. I have a few ideas, but have not made any decisions yet. Maybe=
I
>can get some ideas here to influence me in one direction or another.

Imho it improves safety and comfort.

>I'm interested in ideas on how I might set up LED night lights throughout
>the house.

I'd use a 12v switching regulator off your 48v supply, putting the 12v
down 2 pairs of cat5 wires. 2 pairs gives greater reliability and more
power handling capacity.

If you wanted to make it more useful, use bigger wire or more in
parallel, and you can later add miniature sockets as 12v outlets, with
the emphasis being on miniature. This is a good way to get rid of a lot
of ineffiicient and ugly wallwarts.

>I wonder if it would make sense to power the LED night lights from my main
>48v battery bank, or to use a separate dedicated bank, and maybe at a
>different voltage?

no need for a 2nd battery really.

>My main bank runs at 48v. I suppose it would be easy enough to run a
>dedicated, fused, 48v wiring run..With a 48v run, I would not have as much
>voltage drop across the wire and could use smaller gauge wire. But, would I
>be just burning it off in resistors required to drop the voltage to that
>required by the LEDs?

It may be a bit easier at the supply end, but 48v isnt very useful. By
saving one v dropper you'd need to add many more. And yes, it would
make your LED lights far less efficient.

>Alternatively, I could setup a separate 6v (or 12v) deep cycle golf cart
>battery. This would require periodic recharging, probably with an
>inexpensive automotive charger plugged into my 110vac. I'd almost prefer n=
ot
>to go this route, because it adds one more thing separate subsystem to have
>to monitor and maintain.

no no

>On the other hand, if it were 12v, then I might
>find it useful for other non-nightlight applications such as recharging my
>cell phone where 12v is the more common voltage. DC to DC converters are
>somewhat pricey,

I used to make them for under =A31.

>I am thinking that a single switch per floor would be adequate for my plac=
e=2E
>I wonder if I could just use a normal 110vac light switch for 48VDC, or I
>would need a DC rated switch?

yes, and no, not for LEDs. I would switch each room, as night time
lighting can be very annoying for some people.

>It would be nice if I could use some small gauge wire, like Cat5, or door
>bell wire. Each wire run might be in the range of 100 feet per floor.

A LED light eats 20mA, so you can use just about anything. I'd go with
cat5.

>Is a single led per fixture adequate? Color?

no. Any, but a mixture is better. Monochromatic light is less easy for
the brain to interpret, trichromatic is much easier to deal with. I
would prefer to avoid white LEDs as theyre pointlessly expensive, give
poor a quality white, and dont last well. RGB works like white, if you
want white, and lasts long term.

George Ghio:

>Well if we say each LED needs 3V then 16 leds in series would use 48V.
>No resistors.

It is not a good idea to run LEDs this way. It will make otherwise
reliable devices unreliable.

Ecnerwal wrote:

>The "right" way to run LEDs off a high voltage supply (right being
>efficient) is to set up a constant current supply, since that is
>"really" what LEDs need, not any specific voltage, so much. The number
>of LEDs that can be in a single string is then limited by the voltage.
>ie, one constant current supply run from 12 V can run X LEDs (often 8-10
>of the usual sort of LEDs), and a similar one run from 48V can run 4X
>LEDs, more or less. They will use exactly the same amount of energy to
>run 1 LED, or as many LEDs as they can run, so maximizing LEDs per
>supply is the most efficient approach.

a lot of these points are open to debate imho

>The switch used does need to be DC rated,

no

>and the circuit needs to be fused or have a
>circuit breaker.

Or a safety resistor. However, if you make your 12v line available for
other uses, as I would, then yes use a fuse. The switch mode regulator
will limit the current, you only need a fuse as backup protection, so
its not necessary to use a breaker.

>I'd go with red, as highly efficient red LEDs are available, and red
>does not destroy your night vision, if you are getting up to view the
>stars, or peer out to see if there's a burglar, or that sort of thing.

Thats true, but it has its downside as well. If youre going from a
white lit room into a red lit zone, it does take time to adjust to the
monochromacity. I would choose mixed colours to avoid this mild
discomfort and reduction in visibility. Pink lighting might be a good
compromise!

Specific current will depend on the LEDs, generally 10-30 mA (lower
will
just be dimmer, too high will fry them).

Pretty much all want 20mA. Overdriving them would cause failures.

>If mounting into a switchplate, mount pointing down, I'd think.

pointing up to a white ceiling rather than down to the floor would give
a much more spread light, enabling visibility. Small patches of down
pointing wont, unless you use a whole lot of LEDs scattered around each
room.

Bughunter:

>At this point haven't decided on color or specs for leds. I presume that
>would be one factor I'd have to get nailed down before I tried to make the
>decision on what type of supply would work.

Same supply will run all colours of LEDs. The only difference is that
R,Y,O,G are apx 2v, whereas B,W use a bit more voltage, so you'd use a
different number of those.

>It started out seeming like a simple enough project, and then you discover
>how many decisions there are to be made, number of fixtures, how many leds,
>type of supply, type of mounting, color, esthetics, efficiency....

It can easily stay simple. Use a 12v switched mode regulator to supply
12v on cat5, and use 8-9v of ultrabright LEDs in series at each
lighting point, with a resistor at each lighting point to keep them to
20mA.

You can happily get this up and running with a basic 12v linear
regulator, and swap in a switched mode one as and when. The linear reg
will give you about 20% efficiency, but its 20% x sod all. The switched
mode job will raise this dramatically. 2 resistors, zener and 2x trs
will give a simple linear reg with built in current protection.

>But, I don't think I'd need 16 LEDs for a single night-light. I'm thinking
>that 1-3 might be
>enough (light-wise) for each fixture.

3-4 ultrabrights is good, 1 wont be enough

>I don't think that I want to run
>series strings in the walls although it would be possible. It feels a litt=
le
>like those series strings of xmas lights, where you had to search for the
>bad bulb to fix a string. With the long life of LEDs, it would much less of
>a problem.

I wouldnt either, for other reasons as well.

>Maybe it does make more sense to just use 16 leds and get more
>light rather than just disipating the power in resistors as heat.

Running what you need on 12v will use less energy, cost less and be
simpler to work with.

A 2v 20mA LED eats just 0.04 watts. A lighting point with 4 LEDs will
eat 20mA @ 12v =3D 0.24 watts.

>Thanks for mentioning MPJA.com. I knew I had seen some relatively
>inexpensive dc-dc converters some place.
>http://mpja.com/productview.asp?product=3D7724+PS is way overkill and a bit
>pricey at $60. They also have one for $25, but it requires +5v to activate
>it.

crikey. I made little asynchronous switch mode regulators for under
=A31. 1 or 2 trs, dont remember which, but I think I got them working
with just one.

>I did some very brief research into Ecnerwal's suggestion about a constant
>current supply. This does seem to be the way the pros do it in contemporary
>product design.

ok, but understand something, and this seems to be a tough concept with
newcomers: constant current source does not mean constant current, it
means controlled current. Current needs to be within a useful range, it
need not be constant. This is most easily done with LEDs by limiting
the total LED v drop to around 3/4 the V_supply, and using a resistor
to limit current. Its very simple.

Duane:

>It is definitely not cool to use AC wall switches on DC.
>The problem is the arcing that can happen when opening
>the "AC" switch.

thats true for higher power loads, but not for LED lights. You can use
any switch at all for 12v LEDs, even dolls house switches or paper
clips and drawing pins, whatever you want.

>I have done a bunch of experimenting on how to adapt the
>"AC" switches for use in DC systems. See:
>http://www.redrok.com/misc1.htm#dcswitch

Theres a much easier way: use a capacitor across the switch, with a low
series resistor to protect the switch when it closes.

NT

Bughunter

2005-12-17, 8:21 am

"Ecnerwal" <LawrenceSMITH@SOuthernVERmont.NyET> wrote in message
news:LawrenceSMITH-9A7928.23434416122005@news.verizon.net...
> In article <XxIof.135$dh2.75@trndny08>, "Bughunter" <nobody@home.net>
> wrote:
>
> See if either
>
> www.digikey.com
>
> www.mouser.com
>
> stock them - they are both happy to sell you one, 10, 100 or 10000 (at
> different prices) of various things, though they might have a minimum
> order (but not a large one, and easy enough if you put your shopping hat
> on - grab some LEDs and switches, for instance).
>
> OK, I looked - Mouser has them - $0.70 for 1, $0.52/ea for 1000.
>
> Well, actually there seem to be several options among Supertex CL2,
> probably related to package (ie, tiny surface mount or more useful to
> normal humans leads), and I'm not looking into it in detail as I need to
> get to sleep, but somewhere in that ballpark, and I'm not quickly
> finding a minimum order amount, but have certainly placed small orders
> there in the past, so it can't be too obnoxious.
>
> --
> Cats, coffee, chocolate...vices to live by

Thanks for the link.

I can handle $.70 a piece for a couple of them. Yes, they do come in several
packaging styles. I didn't see anything about a minimum order either, but
there may be one hidden in the checkout. I'll give them a try.

Steve Spence

2005-12-17, 10:21 am

meow2222@care2.com wrote:
> Bughunter wrote:
>
>
>
>
>
>
> Do it. Now is the time to install a bundle of LV wiring for whaetevr
> future uses come along. Lighting, alt power, zoned temp control,
> security, data comms, remote control, and who knows what will become
> useful in future. Running cat5 is very cheap, and it would be a lost
> oportunity not to run it, even if you dont have a specific use right
> now. Its very cheap to run it, and difficult to put in later. You'll
> likely regret it if you dont.
>
> 2x or 3x Cat5 is good because its the leading standard and its
> adaptable. Multicore burglar alarm wiring is also useful.
>

Cat5 cable can't handle much load at 12vdc. It's 24 gauge, and too light
weight. I wouldn't run more than an amp over a 10' distance, too much
voltage drop.

--
Steve Spence
Dir., Green Trust, http://www.green-trust.org
Contributing Editor, http://www.off-grid.net
http://www.rebelwolf.com/essn.html

P. Lyttle

2005-12-17, 11:21 am

Steve Spence wrote:

> meow2222@care2.com wrote:
>
> Cat5 cable can't handle much load at 12vdc. It's 24 gauge, and too light
> weight. I wouldn't run more than an amp over a 10' distance, too much
> voltage drop.
>
>
>
A white superbright runs at 20 mA max. Three in series (10V) plus 100 Ohm
resistance (some of that may be from the cable) goes quite adequate over cat5.
A superbright is more expensive, but you save on cabling (and battery drain)

In many lighting applications it might be beneficial to remove the lens molded
on the LED either by cutting, grinding or sanding (I use a lathe) with the
front polished to reduce backscatter.
This provides a remarkebly bright ambient light.
One of these illuminates my attic, another the sccond floor and staircase.
the third of the triplet is projected in my living room.
I will probably install a second triplet, but just those 6 leds will provide
all the emergency lighting I will need, using cat5, at a 30 mA drain.

As a fiture I use the standard black plastic mounting rings, which will
push-fit in a 6.5 mm hole, like these:
http://www1.nl2.conrad.com/m/1000_1...B_00_FB.EPS.jpg
The wire goes in the back

P. Lyttle

William P.N. Smith

2005-12-17, 11:21 pm

"Bughunter" <nobody@home.net> wrote:
>The recent discussion about LED lighting included a couple comments on the
>appropriateness of LEDS for night lights. I thought it was an idea worthy of
>it's own thread.

I guess it is! I'd look at boat stores for 12V LED lights in
fixtures, though they may be too expensive and/or too flimsy for what
you are looking for. I wandered around a boat store a number of times
looking for just this kind of thing, and was pretty underimpressed.
Catalogs and WWWebsites can be deceiving, you'll want to see them in
person.

The other option is LumiLeds Star 1W emitters driven at maybe 100 mA
and mounted in a standard electric box in the ceiling.

I just keep an LED flashllight by the bed.

William P.N. Smith

2005-12-18, 12:21 am

George Ghio <AKA@nomailhere.com> wrote:
>Well if we say each LED needs 3V then 16 leds in series would use 48V.
>No resistors.

Well, George would say that, but as always he'd be wrong. Never drive
an LED without some kind of current limiting.

meow2222@care2.com

2005-12-18, 5:21 am

Steve Spence wrote:
> meow2222@care2.com wrote:

>
> Cat5 cable can't handle much load at 12vdc. It's 24 gauge, and too light
> weight. I wouldn't run more than an amp over a 10' distance, too much
> voltage drop.

each lighting point uses 20mA. Lets say 4 rooms per floor, thats 160mA
total, with only a percentage of that going to the more remote rooms.
And thats running on 2 pairs in parallel, not one. I think that'll be
fine. Also the system can happily tolerate a little v drop if
necessary.

Bell wire is heavier and very cheap, I'd be tempted to add that in the
wire bundle, and use it for the LEDs. If you use that youve got a
little capacity for other low power 12v devices, though not a lot. One
bell wire run from the centre distribution point to each lighting point
would beef up this capacity considerably, though having the lot on one
single bell wire run is perfectly workable.

If you dont mind spending a little, something heftier, eg 2.5 mm2,
would enable more serious use of 12v distribution. The reason I didnt
suggest that before is the OP seemed reluctant to put even a single
cat5 in, but that is the best option.

I assume the OP would distribute the 12v from the centre of the house,
if necessary running 48v to there first. Any v drop on the 48v line
will not be a problem in this case.

NT

Bughunter

2005-12-18, 7:21 am

"William P.N. Smith" <news05@compusmiths.com> wrote in message
news:ujj9q1hkeftg1in1uq3sfgu35du6e5hgbm@4ax.com...
> "Bughunter" <nobody@home.net> wrote:
>
> I guess it is! I'd look at boat stores for 12V LED lights in
> fixtures, though they may be too expensive and/or too flimsy for what
> you are looking for. I wandered around a boat store a number of times
> looking for just this kind of thing, and was pretty underimpressed.
> Catalogs and WWWebsites can be deceiving, you'll want to see them in
> person.
>
> The other option is LumiLeds Star 1W emitters driven at maybe 100 mA
> and mounted in a standard electric box in the ceiling.
>
> I just keep an LED flashllight by the bed.

I try to keep a hand cranked dynamo led flashlights on each bedstand, but
they have a tendency to wonder off to do other chores.

I guess I am trying to get a little bit of a "gee-wiz effect" as well. I
have a lot of fun explaining to visitors how my off-grid house power system
works, and evangelizing about the benefits of extreme conservation. A string
of led night lights would be one more topic of conversation, as well as
serving a useful purpose.

There have been some great ideas here as I new there would be. I believe
that I'll collect a few components and have an interesting little project to
do on my next prolonged visit to the house.

Duane C. Johnson

2005-12-18, 8:21 am

Hi NT;

NT <meow2222@care2.com> wrote:

> Duane:

[color=darkred]
> thats true for higher power loads, but not for LED
> lights. You can use any switch at all for 12v LEDs,
> even dolls house switches or paper clips and drawing
> pins, whatever you want.

Well, since this thread is titled "Whole house" LED
night lights some reading these posts could hook up
a large number of LEDs. Maybe switching many amps.

Wiring "dolls houses" is one thing with low power
sources such as wall warts or small batteries.

Whole house applications are a different mater.

The whole house battery sources can be very stiff
and capable of delivering hundreds of amps.

[color=darkred]
> Theres a much easier way: use a capacitor across the
> switch, with a low series resistor to protect the
> switch when it closes.

The main failure mode in DC switch applications is not
in the closure but in the opening. As the switch opens
an arc can form and be maintained in a DC circuit.

DC power switches tend to have rapid contact opening
rates and large contact gaps to extinguish the arc.
Many AC switched don't toggle at all with slow contact
opening rates and relatively small gaps.

Simple capacitors and series resistors just aren't
safe enough to be used in the general case where the
specific switch that is used is unknown. My fairly
simple circuits work well. See:
http://www.redrok.com/misc1.htm#dcswitch

Sure, I may violate the best use practices sometimes
for my own uses. But I have some semblance of expertise
to know when I am getting in trouble. I certainly
would not want to post advice with which a reader with
a lower knowledge level could get in trouble.

> NT

Have fun!

Duane

--
Home of the $35 Solar Tracker Receiver
http://www.redrok.com/led3xassm.htm [*]
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George Ghio

2005-12-18, 10:21 am

Never wrong mate. 16 Leds in series would run off 48 volts. BUT as the
charge voltage could reach 60 volts... Well you can see that there is
more to the problem. The whole idea is though that thinking differently
can, and does, solve many problems.

The main point is that Bughunter is at a point where he can play with
the placement and configuration of his lighting before he locks himself
into the usual "Light in the middle of the room" syndrome. No matter
what voltage he wants to use.

Wiring a bare frame is a lot easier than retro fitting after the dry
wall is up.

It is quite possible to double or triple the number of lights used and
still reduce the energy requirement needed for lighting significantly by
placing lights to their best effect for given lumen output.

William P.N. Smith wrote:
> George Ghio <AKA@nomailhere.com> wrote:
>
>
>
> Well, George would say that, but as always he'd be wrong. Never drive
> an LED without some kind of current limiting.

Vaughn

2005-12-18, 10:21 am

"George Ghio" <AKA@nomailhere.com> wrote in message
news:43a5621d$1_2@news.chariot.net.au...
> Never wrong mate. 16 Leds in series would run off 48 volts.

No George, I respectfully think you are wrong this time. I would never
connect Leds to any low impedance source without current limiting. A common
failure mode of any solid state device is a short circuit. If you develop a few
shorted Leds in a string, or if you happen to get the wiring wrong...
Well...you get the picture.

A possible exception is certain Leds that I have seen packaged with some
type of internal regulation/current limiting inside the package.

Vaughn

meow2222@care2.com

2005-12-18, 11:21 am

George Ghio wrote:
> Never wrong mate. 16 Leds in series would run off 48 volts. BUT as the
> charge voltage could reach 60 volts... Well you can see that there is
> more to the problem. The whole idea is though that thinking differently
> can, and does, solve many problems.

They /can/ be run like that, but no-one that knows anything about them
would recommend it, even as a temporary lash-up.

NT

meow2222@care2.com

2005-12-18, 12:21 pm

Duane C. Johnson wrote:
> Hi NT;
>
> NT <meow2222@care2.com> wrote:
>
>
>
>
> Well, since this thread is titled "Whole house" LED
> night lights some reading these posts could hook up
> a large number of LEDs. Maybe switching many amps.
>
> Wiring "dolls houses" is one thing with low power
> sources such as wall warts or small batteries.
>
> Whole house applications are a different mater.

I understood Bughunter was looking at 20mA per switch, on 12v. At that
current, or double or tripple it, I would not be worried about switch
ratings. Even a reed relay could do that. If he goes LED crazy though,
and runs 5A of lights, I'd agree with you entirely.

NT

Ecnerwal

2005-12-18, 5:21 pm

In article <1134895484.295347.70110@g43g2000cwa.googlegroups.com>,
meow2222@care2.com wrote:

> Steve Spence wrote:
>
> each lighting point uses 20mA. Lets say 4 rooms per floor, thats 160mA
> total

If running from 48V with a current-limiting driver such as the Supertex
that was mentioned, 20mA will probably run _all_ the night lights, if
they are put in series. Thus, no trouble at all on Cat 5. With typical
red, green or amber LEDs you should be able to run 20 or so in series
off that supply voltage. Most whites & blues appear to need higher
operating voltage, meaning less LEDs in a single string. Drawing 20mA
per LED is wasteful, especially with 48V available, and simple
regulating parts for it also available.

--
Cats, coffee, chocolate...vices to live by

George Ghio

2005-12-18, 7:21 pm

The fact that all I proposed was a concept, not a complete circuit, does
not make me wrong. There are several technical issues that would need to
be addressed. Not the least of which is the fact that the battery bank
could reach 60 volts with enough amps to vaporise the wiring. Current
limiting is required, yes. A fuse would be handy as well.

But the concept is a possible one.

Vaughn wrote:
> "George Ghio" <AKA@nomailhere.com> wrote in message
> news:43a5621d$1_2@news.chariot.net.au...
>
>
>
> No George, I respectfully think you are wrong this time. I would never
> connect Leds to any low impedance source without current limiting. A common
> failure mode of any solid state device is a short circuit. If you develop a few
> shorted Leds in a string, or if you happen to get the wiring wrong...
> Well...you get the picture.
>
> A possible exception is certain Leds that I have seen packaged with some
> type of internal regulation/current limiting inside the package.
>
> Vaughn
>
>

George Ghio

2005-12-18, 7:21 pm

meow2222@care2.com wrote:
> George Ghio wrote:
>
>
>
> They /can/ be run like that, but no-one that knows anything about them
> would recommend it, even as a temporary lash-up.
>
> NT
>
You are only repeating what I said.

Vaughn

2005-12-18, 7:21 pm

"George Ghio" <AKA@nomailhere.com> wrote in message
news:43a5e373_1@news.chariot.net.au...
> The fact that all I proposed was a concept, not a complete circuit, does not
> make me wrong. There are several technical issues that would need to be
> addressed. Not the least of which is the fact that the battery bank could
> reach 60 volts with enough amps to vaporise the wiring. Current limiting is
> required, yes. A fuse would be handy as well.
>
> But the concept is a possible one.

Of course! Operating LEDs without the slightest current limiting was just
a faulty "concept", not necessarily a complete faulty circuit, so you are not
completly wrong.

Vaughn (why did I bother?)

Ecnerwal

2005-12-18, 8:21 pm

In article
<5Mlpf.310062$zb5.309277@bgtnsc04-news.ops.worldnet.att.net>,
"Vaughn" <vaughnsimonHATESSPAM@att.fake.net> wrote:

> Vaughn (why did I bother?)

Or more to the point, why isn't GG in your kill filter? He earned a
place in mine...I do wish the rest of you wouldn't feed him, it just
keeps him hanging around.

--
Cats, coffee, chocolate...vices to live by

clare at snyder.on.ca

2005-12-18, 8:21 pm

On Sat, 17 Dec 2005 21:55:50 -0500, William P.N. Smith
<news05@compusmiths.com> wrote:

>George Ghio <AKA@nomailhere.com> wrote:
>
>Well, George would say that, but as always he'd be wrong. Never drive
>an LED without some kind of current limiting.

But MANY commercial apps do just that. If the voltage is right, the
current WILL be limitted.

SolarFlare

2005-12-18, 9:21 pm

Must make y'all proud to correct somebody's spelling
huh?

LOL
"Ecnerwal" <LawrenceSMITH@SOuthernVERmont.NyET> wrote
in message
news:LawrenceSMITH-93BD06.18184318122005@news.verizon.net...
> In article
>
<5Mlpf.310062$zb5.309277@bgtnsc04-news.ops.worldnet.att
..net>,
> "Vaughn" <vaughnsimonHATESSPAM@att.fake.net> wrote:
>
>
> Or more to the point, why isn't GG in your kill
filter? He earned a
> place in mine...I do wish the rest of you wouldn't
feed him, it just
> keeps him hanging around.
>
> --
> Cats, coffee, chocolate...vices to live by

SolarFlare

2005-12-18, 10:21 pm

Very damgerous though. A voltage surge may destroy them
like an aircraft in the Trade Center

<clare at snyder.on.ca> wrote in message
news:4pubq117vaf5qie89mn68tf0n1h58jqopt@4ax.com...
> On Sat, 17 Dec 2005 21:55:50 -0500, William P.N.
Smith
> <news05@compusmiths.com> wrote:
>
series would use 4