# power supply advice



## stagehand1975 (Feb 22, 2010)

I have a lanscaped trail in my backyard that will become a haunted trail this halloween. This is a very long trail as I have 18 acres. At the begining of this trail is a 600 watt landscape lighting power supply. It actually has 2 12 volt legs to it at 300 watts each. I believe these put it out in ac although I havent checked. There is one heavy guage cable that runs the majority of the length of this trail. There is allready lanscape lights attached to it, and I have many led lanscape spot lights to attach to it. I want to be able to attach home led lights to it and maybe some other 12 volt items. I am willing to make or purchase some ac to dc cenverters. i am only currently only using 100 watt of one leg of this power supply. 

are my ideas wise and does anyone have any suggestions?:jol:


----------



## TheOneAndOnlyKelly (May 7, 2009)

My advice would be to just try it, to find out the limits of your system. Have someone stand near the power supply to make sure its not overheating, but you should through a breaker/fuse before that becomes an issue...

How old is your train system?


----------



## niblique71 (Dec 2, 2009)

MacabreRob said:


> My advice would be to just try it, to find out the limits of your system. Have someone stand near the power supply to make sure its not overheating, but you should through a breaker/fuse before that becomes an issue...
> 
> How old is your train system?


Most of the Landscape light transformers that I've used already have circuit breakers built into them.

As far as LED Lighting? I believe they will work, but the will go on and off 60 times a second (If your systems puts out 12V A/C at 60 Hrz). That's probably too fast for anyone to notice that they are flickering. It could reduce the life of the LED's, BUT with most rated at many thousands of hours I doubt that will be an issue.

For the 12V A/C to D/C converters?? Some of the more tech savy members will have to answer that one.


----------



## corey872 (Jan 10, 2010)

Guess I am not sure what the exact question is.

The line is most likely AC. For incandescent landscape lights, there is no need to run DC and you could also run into voltage drop issues depending on how long the line is.

As for options

You could use/build a big DC inverter (ie battery charger) and make the whole line DC. 12V LED's would run right off the line, the incandescent's would work too - though maybe a slightly shorter bulb life. You might run into the voltage drop issues with DC in a long line, though.

You could build many small 'local' rectifiers for all your LED lights. This would avoid the voltage drop issue. Incandescent lights would work fine on the AC. This would be the best as far as the lights are concerned, but might be expensive if you have many LED's meaning many small rectifiers.

You could just run the LED's off the AC line. As long as the peak inverse voltage (PIV) of the LED is more than the supply, (as it usually is) they should be fine. The downside is there will be a flicker...some people are sensitive to it, some don't seem to notice.

You could run a complete separate line and run DC on it. The LED lights will draw less current which means voltage drop will be less of an issue, but could still be notable depending on the line length.

You could put a rectifier in the middle of the 12VAC line and run DC lines in opposite directions from there. This would cut the length of the DC line in half.

There is probably a dozen other solutions, too. All depends on how long is 'long' how many of each type of light you want to run, how much you want to spend, how tolerant you are of AC flicker in LED lights, etc.


----------



## stagehand1975 (Feb 22, 2010)

it was more of a suggestions post. the power supply is allready in place. i am not concerned much about voltage drop. I want to use it more for convienience. the 12 guage line is buried for about a 1000 feet and pops out of the ground every 30 feet.


----------



## pshort (May 6, 2008)

The power loss in the line should be the same for DC as for AC, so long as the voltage and current are the same. The benefit of AC is that you can use a simple device (the transformer) to convert between low voltage and high voltage.

Anyway, there are LED lights out there that run off 12VAC (some MR16 lights, in particular, come to mind).

Edit - the rectifiers that corey mentions are dirt cheap (a few pennies each), if you decide to go that path.


----------



## fritz42_male (May 5, 2009)

It purely depends on the lighting you want. I converted much of my garden lighting with the simple addition of some home made LED 'wedge' bulbs. I bought some cheap bridge rectifiers and used these on the bulb to convert the AC to DC.

http://www.jaycar.com.au/productView.asp?ID=ZR1308&keywords=bridge+rectifier&form=KEYWORD

I bought in a pile of little boards that took the rectifier and leds for this but the end result wasn't superb.

http://www.superbrightleds.com/cgi-bin/store/index.cgi?action=DispPage&Page2Disp=/hobby.htm see the MLED and SBL boards.

The EASY route is to buy in MR16 as suggested - plenty of cheap landscape fittings out there that take MR16 and most of the LED MR16 bulbs have built in rectification so they won't care about AC.

Here is a good reliable source of LEDs

http://www.buyincoins.com/search--mr16----1.html

Note the remote control colour changing one - best price I have seen!

They also do a colour changing strip led setup which is good for mood lighting

http://www.buyincoins.com/details/r...-smd-led-strip-remote-power-product-3509.html


----------



## robp790 (Jan 8, 2008)

Superbrightleds.com sells malibu lights cheaply. Leds for the landscape lights depend on the color are between $4 and $6 each. they have color changing leds for $9. I am using one in my house this winter. I have 4 malibu transformers a lots of cable so it was way cheaper to buy these colored bulbs, plus you can put a lot more leds on the run of landscape wire.


----------



## thrilltainment (Apr 8, 2010)

stagehand1975 said:


> I have a lanscaped trail in my backyard that will become a haunted trail this halloween. This is a very long trail as I have 18 acres. At the begining of this trail is a 600 watt landscape lighting power supply. It actually has 2 12 volt legs to it at 300 watts each. I believe these put it out in ac although I havent checked. There is one heavy guage cable that runs the majority of the length of this trail. There is allready lanscape lights attached to it, and I have many led lanscape spot lights to attach to it. I want to be able to attach home led lights to it and maybe some other 12 volt items. I am willing to make or purchase some ac to dc cenverters. i am only currently only using 100 watt of one leg of this power supply.
> 
> are my ideas wise and does anyone have any suggestions?:jol:


if you're gonna run 12V AC on standard LEDs, your LEDs will flicker at 60Hz like someone posted earlier. If you want to further reduce this flicker is if you add a bridge rectifier and a capacitor to smooth out the current ripples.


----------

