landscape lighting

[[email protected]]

We got a 12V outdoor landscape light kit from Big Lots (was about
$30). 20 lights, 4W ea bulb, 100W 12VAC switching power supply.

After a few hours, the power supply burned out. (Yay Made in China.)

I bought a 200W 12VDC transformer from Lowe's ($50!!!) to replace the
power supply. (I'm putting in 8 16W bulbs for spot lighting, leaving
12 4W bulbs, total 176W power, plus line losses.)

I noticed that the light closest to the power supply is brightest, and
the light furthest away is very dim. Even when putting in a 16W bulb
at the end, it's STILL dimmer than the 4W bulb closest to the power
supply.

Would 12V AC solve the dim light problem?

If so, how about pulsed DC? (I'm thinking of connecting a 555,
switching at ~100 Hz, to a 20A MOSFET.)

Why did they bother to rectify the 12V output power, I wonder...

Thanks,

Michael
--
Consider: A million and a half new Americans are murdered every year
by abortion. No other issue involves numbers that high. Nothing short
of a full-scale nuclear or biological war between well-armed nation
states would kill that many people, and we aren’t in imminent danger
of having one of those. Jobs? The economy? Taxes? Education? The
environment? Immigration? Forget it. We do not have nine million
people dying in a typical president’s term of office due to bad job
programs, bad economic policies, bad taxes, bad education, bad
environmental law, bad immigration rules—or even all of these
combined. All of them together cannot provide a reason proportionate
to the need to end abortion. Make no mistake: Abortion is the
preeminent moral issue of our time. It is the black hole that out-
masses every other issue. Presenting any other issues as if they were
proportionate to it is nothing but smoke and mirrors.
http://www.jimmyakin.org/2004/09/what_ratzinger_.html

 

[Alvin Andries]

We got a 12V outdoor landscape light kit from Big Lots (was about
$30). 20 lights, 4W ea bulb, 100W 12VAC switching power supply.

After a few hours, the power supply burned out. (Yay Made in China.)

I bought a 200W 12VDC transformer from Lowe's ($50!!!) to replace the
power supply. (I'm putting in 8 16W bulbs for spot lighting, leaving
12 4W bulbs, total 176W power, plus line losses.)

I noticed that the light closest to the power supply is brightest, and
the light furthest away is very dim. Even when putting in a 16W bulb
at the end, it's STILL dimmer than the 4W bulb closest to the power
supply.

Would 12V AC solve the dim light problem?

If so, how about pulsed DC? (I'm thinking of connecting a 555,
switching at ~100 Hz, to a 20A MOSFET.)

Why did they bother to rectify the 12V output power, I wonder...

Thanks,

Michael

-----------------------------

Hi Michael,

If you measured the voltage at each blb, you would have seen the voltage
drop. I don't know if you are using the original cable or using an home-brew
extension, but you need to carry 16+ amps efficiently. Anything less than
2.5mm^2 (someone will have to convert this to the maximum gauge for the US,
http://www.reade.com/Conversion/wire_gauge.html => gauge 10) would be silly
and even risky due to heating.

Regards,
Alvin.

 

[[email protected]]

We got a 12V outdoor landscape light kit from Big Lots (was about
$30). 20 lights, 4W ea bulb, 100W 12VAC switching power supply.

After a few hours, the power supply burned out. (Yay Made in China.)

I bought a 200W 12VDC transformer from Lowe's ($50!!!) to replace the
power supply. (I'm putting in 8 16W bulbs for spot lighting, leaving
12 4W bulbs, total 176W power, plus line losses.)

I noticed that the light closest to the power supply is brightest, and
the light furthest away is very dim. Even when putting in a 16W bulb
at the end, it's STILL dimmer than the 4W bulb closest to the power
supply.

Would 12V AC solve the dim light problem?

If so, how about pulsed DC? (I'm thinking of connecting a 555,
switching at ~100 Hz, to a 20A MOSFET.)

Why did they bother to rectify the 12V output power, I wonder...

Thanks,

Michael

-----------------------------

Hi Michael,

If you measured the voltage at each blb, you would have seen the voltage
drop. I don't know if you are using the original cable or using an home-brew
extension, but you need to carry 16+ amps efficiently. Anything less than
2.5mm^2 (someone will have to convert this to the maximum gauge for the US,http://www.reade.com/Conversion/wire_gauge.html=> gauge 10) would be silly
and even risky due to heating.

Regards,
Alvin.

It's 100 ft of whatever wire they included in the landscape kit. Good
point, maybe I should go for something thicker... (I didn't notice it
getting warm, though.)

Thanks,

Michael

 

[[email protected]]

We got a 12V outdoor landscape light kit from Big Lots (was about
$30). 20 lights, 4W ea bulb, 100W 12VAC switching power supply.

After a few hours, the power supply burned out. (Yay Made in China.)

I bought a 200W 12VDC transformer from Lowe's ($50!!!) to replace the
power supply. (I'm putting in 8 16W bulbs for spot lighting, leaving
12 4W bulbs, total 176W power, plus line losses.)

I noticed that the light closest to the power supply is brightest, and
the light furthest away is very dim. Even when putting in a 16W bulb
at the end, it's STILL dimmer than the 4W bulb closest to the power
supply.

Would 12V AC solve the dim light problem?

If so, how about pulsed DC? (I'm thinking of connecting a 555,
switching at ~100 Hz, to a 20A MOSFET.)

Why did they bother to rectify the 12V output power, I wonder...

Thanks,

Michael

-----------------------------

Hi Michael,

If you measured the voltage at each blb, you would have seen the voltage
drop. I don't know if you are using the original cable or using an home-brew
extension, but you need to carry 16+ amps efficiently. Anything less than
2.5mm^2 (someone will have to convert this to the maximum gauge for the US,http://www.reade.com/Conversion/wire_gauge.html=> gauge 10) would be silly
and even risky due to heating.

Regards,
Alvin.

Great point - a quick solution would be, instead of using one 100-ft.
wire of unknown gauge to light up 20 lights, break it up into two
parallel 50-ft sections of wire, each lighting up 10 lights. That
should do the trick...

Michael

 

[Joerg]

We got a 12V outdoor landscape light kit from Big Lots (was about
$30). 20 lights, 4W ea bulb, 100W 12VAC switching power supply.

Malibu? Hmm, still pricey. IMHO it's not of very high quality so we
usually wait until it goes on sale and HD or Lowes for $20 or $25. Main
reason is that their timers are really lousy, they don't last. But I
always make sure there is not switcher in there.

After a few hours, the power supply burned out. (Yay Made in China.)

No surprise there :-(

I bought a 200W 12VDC transformer from Lowe's ($50!!!) to replace the
power supply. (I'm putting in 8 16W bulbs for spot lighting, leaving
12 4W bulbs, total 176W power, plus line losses.)

I noticed that the light closest to the power supply is brightest, and
the light furthest away is very dim. Even when putting in a 16W bulb
at the end, it's STILL dimmer than the 4W bulb closest to the power
supply.

Would 12V AC solve the dim light problem?

Nope.


If so, how about pulsed DC? (I'm thinking of connecting a 555,
switching at ~100 Hz, to a 20A MOSFET.)

Nope again. The cable that comes with these kits is kind of wimpy for
the current so you'll pretty much have to live with the voltage drop.
Unless you want to build a little switcher for each bulb and then your
radio will probably carry a nice background buzz. Professional
landscaping has larger cable but the connectors are very different and I
doubt the Malibu ones would fit.

Why did they bother to rectify the 12V output power, I wonder...

No idea. For light bulbs it doesn't make sense. Only one reason I could
think of: A cheap switcher can only generate DC and maybe it was a few
milli-cents lower in cost than the transformer.

 

[[email protected]]

Malibu? Hmm, still pricey. IMHO it's not of very high quality so we
usually wait until it goes on sale and HD or Lowes for $20 or $25. Main
reason is that their timers are really lousy, they don't last. But I
always make sure there is not switcher in there.

Yep it's a Malibu. They go on sale? It's very, very heavy so I doubt
it's a switcher.

~snip~

Nope again. The cable that comes with these kits is kind of wimpy for
the current so you'll pretty much have to live with the voltage drop.
Unless you want to build a little switcher for each bulb and then your
radio will probably carry a nice background buzz. Professional
landscaping has larger cable but the connectors are very different and I
doubt the Malibu ones would fit.

K, thanks for saving me the time to build it, make it weather-proof,
then discover it doesn't help anyway.

No idea. For light bulbs it doesn't make sense. Only one reason I could
think of: A cheap switcher can only generate DC and maybe it was a few
milli-cents lower in cost than the transformer.

I went to the Surplus Store on Folsom Blvd. They had some IIRC 15VDC,
7A switching power supplies for IBM laptops, $12.

Would have been perfect, but 1) not for outdoor use, and 2) we wanted
brighter lights for the spot lights, exceeding the 100W point...



Thanks,

Michael

 

[[email protected]]

On Jun 11, 12:29 pm, "Alvin Andries"

~snip~

Hi Michael,

If you measured the voltage at each blb, you would have seen the voltage
drop. I don't know if you are using the original cable or using an home-brew
extension, but you need to carry 16+ amps efficiently. Anything less than
2.5mm^2 (someone will have to convert this to the maximum gauge for the US,http://www.reade.com/Conversion/wire_gauge.html=> gauge 10) would be silly
and even risky due to heating.

Regards,
Alvin.

The wire is 18 gauge I believe. Those Chinese vendors...

I cut the wire into two ~50-foot pieces and connected them in parallel
to the 200W power supply. One leg has 10x4W bulbs; the other leg has
8x4W bulbs and 2x16W bulbs. (I haven't gotten around to buying 4 more
16W bulbs yet.)

40W... that's a bit less than 4A.

Ultimately, each leg will have 7x4W and 3x16W... 28+48W... 76W total.
Just under 7A.

And the lights are pretty much the same brightness now! If you look
REALLY closely you can tell the last bulb is a LITTLE dimmer than the
first one... but only if you know where to look.

Anyone know where I can get LED landscape lights for cheap? At $4
each from a web vendor, I calculate breakeven time to be 3 years
electricity-wise. On the other hand, I won't have to worry about my
house burning down from hot lamps...

Thanks,

Michael

 

[Paul Carpenter]

On Jun 11, 12:29 pm, "Alvin Andries"

~snip~



The wire is 18 gauge I believe. Those Chinese vendors...

Practically all of this type of consumer product is made in China or
similar locations, whatever the brand name is.

I cut the wire into two ~50-foot pieces and connected them in parallel
to the 200W power supply. One leg has 10x4W bulbs; the other leg has
8x4W bulbs and 2x16W bulbs. (I haven't gotten around to buying 4 more
16W bulbs yet.)

40W... that's a bit less than 4A.

Hmm.. several types of Landscape Lighting in UK have connectors allowing
two cable connections, and run in a 'ring' configuration, the wire is
heavier gauge, has a rib on one conductors insulator so polarity can be
determined. This is important when when closing the 'ring', otherwise you
end up with a short.

In your case run a second cable from transformer/PSU to last light in
chain completing the 'ring'.

Most UK ones I have seen are 12V AC, from a transformer with self-
resetting output overload (short) and thermal protection. The
transormer is normally expected to be used indoors and the lighting cable
run through a wall. Our loop length is over 30m.

Ultimately, each leg will have 7x4W and 3x16W... 28+48W... 76W total.
Just under 7A.

And the lights are pretty much the same brightness now! If you look
REALLY closely you can tell the last bulb is a LITTLE dimmer than the
first one... but only if you know where to look.

.....

I Even put in an external box to run a 5V DC water feature off of the
ring so replaces the solar panel drive at night time.

--
Paul Carpenter | [email protected]
<http://www.pcserviceselectronics.co.uk/> PC Services
<http://www.pcserviceselectronics.co.uk/fonts/> Timing Diagram Font
<http://www.gnuh8.org.uk/> GNU H8 - compiler & Renesas H8/H8S/H8 Tiny
<http://www.badweb.org.uk/> For those web sites you hate

 

[Ban]

Consider: A million and a half new Americans are murdered every year
by abortion. No other issue involves numbers that high. Nothing short
of a full-scale nuclear or biological war between well-armed nation
states would kill that many people, and we aren’t in imminent danger
of having one of those. Jobs? The economy? Taxes? Education? The
environment? Immigration? Forget it. We do not have nine million
people dying in a typical president’s term of office due to bad job
programs, bad economic policies, bad taxes, bad education, bad
environmental law, bad immigration rules—or even all of these
combined. All of them together cannot provide a reason proportionate
to the need to end abortion. Make no mistake: Abortion is the
preeminent moral issue of our time. It is the black hole that out-
masses every other issue. Presenting any other issues as if they were
proportionate to it is nothing but smoke and mirrors.http://www.jimmyakin.org/2004/09/what_ratzinger_.html

Hi dimbulb, I wonder what this stupid drivel has to do in this group.
Not only are your numbers wrong, but also is your argumentation.
Do you really want a milion more black and mexican kids on the street
with single mothers on public support? Or are you a holier than thou
Opus_Dei fan? Remember it's guys like you who make those poor women
pregnant not using condoms, prohibited by Ratzinger hypocrites.

 

[Joerg]

Yep it's a Malibu. They go on sale? It's very, very heavy so I doubt
it's a switcher.

But above you mentioned it's a switcher

The heavy big black Malibu boxes are transformers. And yeah, while the
transformers alone never go on sale those 20-count light sets with
timer-transformer do.

~snip~



K, thanks for saving me the time to build it, make it weather-proof,
then discover it doesn't help anyway.

Other than the voltage drop the cables are good, we've got some here
that are about 10 years old. The lamps break at times, the plastic gives
in under the permanent UV pelting. Becomes brittle, then comes a storm
and the pieces fly about.

What is IMHO the pits are the Malibu timers. One of the plastic gears
gives out after very few years, sometimes less than two years. Of course
you can't get them individually. They didn't even respond to my request.
A typical case where they could command much higehr prices if they built
better stuff. But this way we only buy at rock bottom price.

I went to the Surplus Store on Folsom Blvd. They had some IIRC 15VDC,
7A switching power supplies for IBM laptops, $12.

Would have been perfect, but 1) not for outdoor use, and 2) we wanted
brighter lights for the spot lights, exceeding the 100W point...

Make sure it's outdoor rated or have them in a protected location with
all the safety features around them.

BTW if I don't answer you on s.e.d. that is because you are using gmail
and I had to block that whole domain there to reign in the barrage of
spam. So I don't see any post from the Google domain there. Had no choice.

 

[C. Nick Kruzer]

Why did they bother to rectify the 12V output
power, I wonder... ?

Joerg's reply:

No idea. For light bulbs it doesn't make sense.
Only one reason I could think of: A cheap
switcher can only generate DC and maybe it
was a few milli-cents lower in cost than the
transformer.

Another reason for DC might be that it is safer (from electric shock)
than AC. Landscape wiring means exposure to the effects of weather.

insula

 

[[email protected]]

On Jun 12, 7:33 am, Joerg <[email protected]>
wrote:

....

But above you mentioned it's a switcher

Ah I see what you mean now. The power supply that came with the light
kit was a switcher. It lasted maybe 2-3 hours, with the stock 4W
bulbs. Only 18 lights were installed, too - I had to make
"modifications" to 2 lights, which had bad wiring out of the box.
(bent connectors, loose wires.)

The heavy big black Malibu boxes are transformers. And yeah, while the
transformers alone never go on sale those 20-count light sets with
timer-transformer do.

I'll keep an eye out.

....

Other than the voltage drop the cables are good, we've got some here
that are about 10 years old. The lamps break at times, the plastic gives
in under the permanent UV pelting. Becomes brittle, then comes a storm
and the pieces fly about.

What is IMHO the pits are the Malibu timers. One of the plastic gears
gives out after very few years, sometimes less than two years. Of course
you can't get them individually. They didn't even respond to my request.
A typical case where they could command much higehr prices if they built
better stuff. But this way we only buy at rock bottom price.



....

Make sure it's outdoor rated or have them in a protected location with
all the safety features around them.

It's outdoor rated, but says to place it 1 foot above the ground. I
don't have a magnetic levitation device handy, and I'm really
reluctant to drill into my stucco just to accommodate this request.
Are they expecting arcing between the transformer, through the
plastic, to ground?

BTW if I don't answer you on s.e.d. that is because you are using gmail
and I had to block that whole domain there to reign in the barrage of
spam. So I don't see any post from the Google domain there. Had no choice.

No problem. Thanks for answering me here.


Michael

 

[C. Nick Kruzer]

mrdarrett:

I noticed that the light closest to the power
supply is brightest, and the light furthest away
is very dim. Even when putting in a 16W bulb at
the end, it's STILL dimmer than the 4W bulb
closest to the power supply.

Sounds like it should have higher voltage.

Would 12V AC solve the dim light problem?

Although AC is better than DC with remote distances from power source,
the voltage might still be too low.

insula

 

[[email protected]]

Joerg's reply:


Another reason for DC might be that it is safer (from electric shock)
than AC. Landscape wiring means exposure to the effects of weather.

insula

12V AC is less safe than 12V DC?

How so?

Thanks,

Michael

 

[[email protected]]

Hi dimbulb, I wonder what this stupid drivel has to do in this group.
Not only are your numbers wrong, but also is your argumentation.
Do you really want a milion more black and mexican kids on the street
with single mothers on public support? Or are you a holier than thou
Opus_Dei fan? Remember it's guys like you who make those poor women
pregnant not using condoms, prohibited by Ratzinger hypocrites.

I speak the truth, in the hope that others may listen.

Michael

 

[Sjouke Burry]

Joerg's reply:


Another reason for DC might be that it is safer (from electric shock)
than AC. Landscape wiring means exposure to the effects of weather.

insula

You get shocked by 12 volts ??????????
And by the way, dc is sneakier then ac,
it just tingles less.
And dc is much more corrosive in wet surroundings.

 

[Joerg]

On Jun 12, 7:33 am, Joerg <[email protected]>
wrote:

...



Ah I see what you mean now. The power supply that came with the light
kit was a switcher. It lasted maybe 2-3 hours, with the stock 4W
bulbs. Only 18 lights were installed, too - I had to make
"modifications" to 2 lights, which had bad wiring out of the box.
(bent connectors, loose wires.)

Not too unusual with Malibu stuff.

I'll keep an eye out.

...



It's outdoor rated, but says to place it 1 foot above the ground. I
don't have a magnetic levitation device handy, and I'm really
reluctant to drill into my stucco just to accommodate this request.
Are they expecting arcing between the transformer, through the
plastic, to ground?

Maybe they don't want it to sit in a puddle after a rain storm. However,
looking at pictures from back east 1ft ain't much.

[...]

 

[Joerg]

mrdarrett:


Sounds like it should have higher voltage.

That would lead to frequent blowouts of the bulbs closer to the power
source and Malibu lights don't have much of an endurance to begin with.

Although AC is better than DC with remote distances from power source,
the voltage might still be too low.

At least AC helps a little bit with corrosion. This stuff will be
exposed to the elements, including sprinkler systems. Plus the
occasional leg lifting of furry friends, bird droppings, pesticide
spraying, you name it.

 

[Joerg]

[email protected] wrote:

[...]

Anyone know where I can get LED landscape lights for cheap? At $4
each from a web vendor, I calculate breakeven time to be 3 years
electricity-wise. On the other hand, I won't have to worry about my
house burning down from hot lamps...

You can get some really fancy one from Lowes:
http://www.lowes.com/lowes/lkn?action=productDetail&productId=284364-17771-WT-S36-4&lpage=none

Her are some more:
http://www.lowes.com/lowes/lkn?acti...=7000&category=Landscape Lighting&N=0+5000757

Of course, in a front yard this stuff might grow legs overnight and vanish.

 

[[email protected]]

[email protected] wrote:

[...]

Anyone know where I can get LED landscape lights for cheap? At $4
each from a web vendor, I calculate breakeven time to be 3 years
electricity-wise. On the other hand, I won't have to worry about my
house burning down from hot lamps...

You can get some really fancy one from Lowes:http://www.lowes.com/lowes/lkn?action=productDetail&productId=284364-...

Her are some more:http://www.lowes.com/lowes/lkn?action=productList&No=108&Ne=7000&cate...

Of course, in a front yard this stuff might grow legs overnight and vanish.

Yep, no kidding.

I was thinking of alternatives to these, at $4 each (for white):
http://www.superbrightleds.com/malibu.htm

I don't think Lowe's carries these, but I've been wrong before...

Regards,

Michael