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Discussion Starter · #1 ·
I'm wanting to find an low-voltage LED post lamp for the entrance to my driveway, that's fed by 12v landscape wiring. For the life of me I cannot find one anywhere. Does anyone know if such a thing exists? If not - why not? It almost seems as if they are illegal or something. If so - why?

There are tons of solar LED lights, and there are tons of 120V lights of course, including a bunch of LED ones.

I have a long driveway (250'), and really don't want to run 120V out to the end - I have some fairly rocky ground and lots of trees, and it's just not worth it for me (I'm guessing would probably be $1-2k to have an electrician do it). I'm running landscape wiring (10/2) up the driveway to do pathway lights, and want to put a lamp post light at the end. This would be two runs, each with only about 30 watts, so I know it's do-able from an electrical standpoint. I see 30-watt LED lights for 12v landscape circuits - but they're all floodlights, not lamp post lights. All I need is about a 10-12 watt light!

Any ideas or info? Is there some national code that prevents such a light from existing? Or it is something that no company has bothered to put on the market? Seems like something that would be desirable!

Closest thing I can find is one Tru-Post light on Amazon that's a "post top" light, but it's pretty much just a basic path light equivalent, at 150 lumens. I'd like to get something that's more like 500 lumens or so, and more stylish.

Thanks.
 

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I'm not sure how code compliant it is, but you could use a normal light fixture of your choosing with 12 volt LED light bulbs (they screw into the normal bases).

Are you running low voltage the full length of the 250' driveway? You may run into some voltage drop issues...

Edit to add: here are some of those 12 volt bulbs: https://www.amazon.com/Voltage-Equivalent-12volt-Battery-Interior-Lighting/dp/B07HB7CX3N

Sent from my new phone. Autocorrect may have changed stuff.
 

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Meet Ohm's Law.

E (voltage drop/loss) = I (current in amps) x R (wire resistance).

Let's say you use 12 AWG wire out there, so the wire resistance will be 0.8 ohms at 250' round trip. And your light is 12 watts.

You run this thing on 120V. 12 watts at 120V is 0.1 amps.

Our voltage *drop* E is 0.1 A x 0.8 ohms. So I get 0.08 volts. So you actually get 119.92 volts to run the lamp, or about a 0.07% drop. That's not so bad.

You run this thing on 12V. 12 watts at 12V is 1.0 amps. Since voltage is 1/10, current must be 10x. Ohm's Law might be a problem.

Our voltage *drop* E is 1.0 A x 0.8 ohms. I get 0.8 volts. So you actually get 11.2 volts or about a 7% drop. That's livable. But you wouldn't want to take it a whole lot further.

If you tried 48 watts, then the 120VAC voltage drop becomes 0.27% and the DC drop becomes 27%. Now we've got a problem! However one solution is to go to 24VDC lighting. Same advantages, less disadvantage.

Anyway, you just use a normal post lamp with an Edison E27 base, and fit a 12V "RV style" screw-in LED out there. These have E27 Edison bases, but operate on 12V or 12-24V. (Kevin has found some six for $20. Wow!) You must be very careful not to put these into 120V sockets. or boom! But that was also true when they were incandescent, so that isn't really new.
 

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(Kevin has found some six for $20. Wow!) You must be very careful not to put these into 120V sockets. or boom! But that was also true when they were incandescent, so that isn't really new.
I posted the first amazon link from googling "12 volt led bulb" that had standard light base (E26).

I have an incandescent 12 volt bulb kicking around. It's in a keyless light fixture that we wrote 12 VOLTS all over so we don't blow it up by accident.

Personally, I'd run the 120 volts rather than low voltage wiring... if you want to put up Christmas lights or something, you'll have the power there... but voltage drop will screw with this... larger the load larger the VD... but LED Christmas lights shouldn't be an issue, as long as it's not 3000' of them.

Sent from my new phone. Autocorrect may have changed stuff.
 

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Discussion Starter · #5 · (Edited)
Thanks guys - that's awesome, and probably what I'll end up doing. After posting I did some more looking and found another thread that mentioned doing the same thing. Did manage to find a couple of 12v fixtures, but none that very good - too dim or just not very attractive. (This was an... interesting... one: https://www.voltlighting.com/outdoo...area-lighting-coachman-black/p/VPL-1006-4-ABK)

FYI I've already ordered 10/2 wire from Amazon - 500' of the stuff. Knowing that I could potentially be pushing the limits I wanted to go ahead and get serious with the wire (the lights themselves will be the bulk of the cost).

For the Christmas lights thing - I thought about that, but my setup is such that there's not really a need for that. The top of my driveway is quite woods-ey (there's a section of woods between my yard and the road), and I do all my lights back at the house.

Thanks again for the help. I may post pics at some point.

I've found some pretty good online calculators and spreadsheets - FX Luminaire had what looks like a really good spreadsheet for calculating runs - what wiring and what transformer is needed. Will probably get a 200W or maybe 300W transformer; need to research those more.

Plan is to do probably 15 path lights, plus this light at the top. Looking at the calculators that's probably too much to do with just one run, so I'm going to break it into two - e.g. do one 150' run feeding 10 path lights (3W each), and the other longer run feeding 5 path lights plus the post.
 

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Discussion Starter · #6 · (Edited)
Here was an attempt I had made last year - a solar light; what I'm looking to replace. It wasn't bad, but being solar it just didn't cut it - it was pretty dim, and on cloudy days it didn't really light up at all at night. I'll move this into a garden area behind the house.



 

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Discussion Starter · #12 ·
Pics from setup test yesterday (started raining right as I was finishing up). Turning out great! The light I got used the candelabra bulbs. I'm trying a few variations of path lights. Thanks again for the help. Those 12v bulbs are a life saver.





When all is said and done I'll have about 12-15 of them going down the driveway.
 
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