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Discussion Starter #1 (Edited)
I have a pretty long driveway.......and I have a lamp post near the house, but is useless for how far away it is, except for taking care of the sidewalk and porch.

At night, the mid section and end of the driveway is pitch black, making it difficult to see pulling in/out, and less security, since there are also dense woods surrounding our house.

I have seen commercial parks have this setup, and I've always wondered, but usually this would only concern line voltage.
I would line the driveway with stake lights, but they would get damaged quickly due to the fact that people are constantly making u-turns on our driveway, and it is very narrow.

I plan on purchasing a low voltage lighting system and illuminating the driveway, and placing multiple LED floods and stakes around our 1/2 acre property for security. I would have the transformer hooked up in our garage via with a remote control switch for the lights when needed on our property.

Is it against code to mount 12 volt flood lights on the trees aiming towards the driveway?
 

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A "Handy Husband"
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Certainly not any national codes.

Best bet is low voltage with LED lamps.

Low burial depth.
Low power requirements.

Solar is not ready for prime time.
 

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Discussion Starter #3
Certainly not any national codes.

Best bet is low voltage with LED lamps.

Low burial depth.
Low power requirements.

Solar is not ready for prime time.

Thankyou very much!

3 more questions......

- The wire needs to run across the garage to where the transformer will be since thats the only outlet (it will be stapled insulated staples to the ceiling and run down the wall), when it exits through the wall, should I bring it through 1/2" PVC conduit for protection through the wall into the ground?

- I always see/here of problems with the small quick connectors that stab through the wire for the lights, and wonder if it would be better to wire nut each connection and tape it? Maybe even with waterproof wire nuts? I'm not to concerned about them shorting out since its only 12v, but I don't want to have to dig them up because the quick-connection corroded and fell apart.

- I plan on using the following 150 watt power pack, and 16 gauge wire since the run is around 75-100ft. If I understand correctly, 16ga wire is good for around (120v 1200w 10a), but (12v 150w is 12.5a)?

Does this mean that I would overload the 16ga wire if I loaded it to 150w? (I know this would max out the transformer, but I plan on only loading to about 120w)

http://www.ebay.com/itm/150-Watt-12...586?pt=LH_DefaultDomain_0&hash=item20c400ab02
 

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A "Handy Husband"
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Yes sleeve the wire with PVC conduit to prevent damage.

I agree on the flimsy stab connections, use WP wire nuts.

Wire size, here we disagree. I would use #12 direct burial landscape wire, #16 is much too small. With #12 at 100 feet with a load of 10 amps, the voltage drop will be about 3 volts. With # 16 the VD would be over 8 volts.
 
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BIGRED
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Is that 150W rating on the 120vac side or on the 12 volt side? Is the 12 volt side rectified for DC or is it AC in and AC out. LEDs are generally DC devices and because DC is harder to push through wires, generally require larger gauge wire. Sixteen ga. wire might do all right for AC, but could be a bit of a stretch for DC. A lot of the installations around here use direct burial 14ga. two conductor cable to be on the safe side. Any of the LED devices for low voltage lighting should be checked to see if (before you buy) they are rated for DC or do they have internal wiring so that they can operate AC/DC. The connectors can be the pin prick type if you are using stranded wire or wire nuts if you choose solid wire. A little trick to waterproof the splice or butt connection is to take a 6" long x 3-4" wide piece of duct tape and lay a 3/8" -1/2" bead of silicone down the middle of the 6" run. Lay the splice or connection down in the middle of the tape and roll the tape around the connection much like rolling a cigarette. It's messy but it lasts 6-7 times longer than just a direct burial connection.
 

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Most landscape lighting transformers are made for ourdoor use only.
 

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BIGRED
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JBFAN: I know they are intended for outdoors, but they normally power incandescent bulbs not LEDs. Just trying to understand what he is trying to do.:huh:
 

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With #12 at 100 feet with a load of 10 amps, the voltage drop will be about 3 volts. With # 16 the VD would be over 8 volts.
I would go with #10 low voltage wire minimum. I calculate VD at 4.1 V with #12's and that is a 33% drop.

If you went with 10's, the drop would be around 2.5 V or about 21% drop.

(with the same numbers...10A @ 100')
 
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BIGRED
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k buz I would say 10ga also and probably should have, but 10 ga. gets pricey and even if he has a 100' drive I doubt he will have lights all the way out on the edge of the road. In fact if he splits the feed to be on both sides of the drive sporaticly he might only have 80' runs and fewer LEDs on a single run.
 

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i would go with line voltage, pop out every so often, up a tree and mount one of those two bulb fixtures.
 

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Discussion Starter #11
Most landscape lighting transformers are made for ourdoor use only.
I know......I am trying to find a moderatly priced (under $50) one that is for indoor/outdoor, but have only found the one I listed to be suitable for my need. The only outdoor outlet I have is in the front, where I need the lighting. But I don't want a big box hanging on by the front door. Thats whey I chose the garage, which is only 10ft away. The outlet is a GFCI, it also controls our lamp post and holiday lights, so I though it would be a good hidden spot. I really don't see a problem with them being inside, as I will be running the wire through through the wall in conduit (whether its really needed or not) :) My neighbors timer is mounted in there laundry room, in the house, and the wire runs bare right through the drywall, plywood, insulation, and vinyl. I suggested at least conduit to bring it to somewhat of a code, and he said "Oh, it meets code already" :whistling2:

JBFAN: I know they are intended for outdoors, but they normally power incandescent bulbs not LEDs. Just trying to understand what he is trying to do.:huh:
Half of it will be LED, half will be basic, but I will still be only around 130w or less for the whole load.

k buz I would say 10ga also and probably should have, but 10 ga. gets pricey and even if he has a 100' drive I doubt he will have lights all the way out on the edge of the road. In fact if he splits the feed to be on both sides of the drive sporaticly he might only have 80' runs and fewer LEDs on a single run.
10ga does get pricey. I was trying not to even go to 12ga if I had to. The wire is too pricey for the runs I have. Not sure how this question will turn out....but........"What if I used 10ga speaker wire?" :laughing: Its cheap! May not be sunlight or water resistant, but I don't mind replacing the "main run" every 5-10yrs for the price of it. I am only doing one side of he driveway, the other side is too close to my neighbors, and too high traffic.
http://www.ebay.com/itm/IMC-Audio-1...25?pt=Speakers_Subwoofers&hash=item53eb728979

i would go with line voltage, pop out every so often, up a tree and mount one of those two bulb fixtures.
I think it would be against code to mount line voltage anything to trees or plants. Besides, 12" deep even at a minimum if GFCI protected for the wire would be impossible with the oak trees roots lining the driveway. I'll be lucky to get down 3"-5" just for the LV wire. Although, I'd like it to be about 6"-8" for protection.
 

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I think it would be against code to mount line voltage anything to trees or plants. Besides, 12" deep even at a minimum if GFCI protected for the wire would be impossible with the oak trees roots lining the driveway. I'll be lucky to get down 3"-5" just for the LV wire. Although, I'd like it to be about 6"-8" for protection.
410.36(G) explicitly allows luminaries to be attached to trees. but pay attention to 225.26, which prohibits the use of vegetation as a means of overhead conductor support. basically, you can't run bare wire from tree-to-tree above the ground. running underground and popping up at each tree, with a light mounted to the tree, is acceptable.

'acceptable' assuming it is a listed outdoor fixture, conductors are installed properly, etc.
 

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Discussion Starter #13
Alright! I went with low voltage. I ordered a 150w powerpack (it says indoor or outdoor use, not sure if it really means anything). Hopefully all goes well. I added up 142w of lights that I will have when its all over (its going to take some time). Going to run security lights down the driveway, uplight the house and some plants, back patio, and add path lights on the side of our house.

I will either be getting 14ga or 12ga wire. Probably 12ga for at least the first 2 50ft main runs out of the garage, and 14ga for splitting off to lights.

1/2" conduit will be installed through the wall on each side of the garage (opposite sides of garage door), with a conduit body junction box, caulked, and the ends duct sealed for the wires to prevent bugs from entering, running down into the ground (probably overkill, but, I don't want to have to fix anything except burnt out bulbs for at least 10yrs.

Thanks for all the help guys! :)

Last quick question: I know it says "225.26, which prohibits the use of vegetation as a means of overhead conductor support. basically, you can't run bare wire from tree-to-tree above the ground. running underground and popping up at each tree, with a light mounted to the tree, is acceptable.".

Does this go for low voltage lighting too, or just line voltage? Because 3 of the trees I will be running low voltage lights, the trees are only 5-7ft away, and I was going to have the wire go from one tree, to the other for a few. It would be alot less wiring......if not, then an extra 10-15' of wiring won't hurt.....but I figured it would be less likely damaged from groundhogs from tree-tree then buried.
 

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Last quick question: I know it says "225.26, which prohibits the use of vegetation as a means of overhead conductor support. basically, you can't run bare wire from tree-to-tree above the ground. running underground and popping up at each tree, with a light mounted to the tree, is acceptable.".

Does this go for low voltage lighting too, or just line voltage? Because 3 of the trees I will be running low voltage lights, the trees are only 5-7ft away, and I was going to have the wire go from one tree, to the other for a few. It would be alot less wiring......if not, then an extra 10-15' of wiring won't hurt.....but I figured it would be less likely damaged from groundhogs from tree-tree then buried.
as far as i understand it, it doesn't matter what the voltage is but i don't have a lot of experience with this. i mean, folks dangle christmas lights all over the place and that's line voltage. beats me...
 

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Is that 150W rating on the 120vac side or on the 12 volt side? Is the 12 volt side rectified for DC or is it AC in and AC out. LEDs are generally DC devices and because DC is harder to push through wires, .
1- If theres 150w at the secondary, then there must be at least 150w at the primary. (actually a little more at primary, to allow for losses).

2 - dc is NOT harder to push thru cable, when compared to ac.
The same rule applies for ac and dc.
And the losses will be the same.

You can always put some extra volts in, if the run is long
and losses are significant.
 

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1- If theres 150w at the secondary, then there must be at least 150w at the primary. (actually a little more at primary, to allow for losses).

2 - dc is NOT harder to push thru cable, when compared to ac.
The same rule applies for ac and dc.
And the losses will be the same.

You can always put some extra volts in, if the run is long
and losses are significant.
Not true. There is more resistance to AC current due to the skin effect that causes current to travel primarily towards the surface of the wire.

Mark
 

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In a system like this IE "60Hz" the losses due to skin effect,
would be so small, it would not even be worth worring about !

It is only significant at much higher frequencies like RF.
 
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