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I have a customer with a 400amp service and a huge piece of land. He wants two LED pole lights put up. The first pole will be 385 feet away from the meter and the second will be 265 feet farther. How do I do this? I know voltage drop is an issue, but I don't quite understand it. Right now my plan is to run a three wire #4 from the meter to the first pole and put a 240v 30amp panel. Then run another three wire #4 to the second pole and put in a 240v 20a panel. I would separate neutrals and grounds at each panel and install a ground rod at each pole. Each panel would have a receptacle and Dusk to Dawn light. Does this work? OR do I have to plan for voltage drop from all the way back (650') at the meter for the second pole? Thanks! -John
 

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Beam Me Up Scotty
Elechicken
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Why the panels?

If you wanted to do it without the panels, I'd base my voltage drop off the known loads and the lengths.

Throwing panels in there will still work, but I'd go larger than #4 to the first one, I'd probably do #1 aluminum or even 1/0.

Oh, and use aluminum, but I'm sure you Know that
 

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Beam Me Up Scotty
Elechicken
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Would you run from the meter to the poles in 120? How would you go from #4, to a #12 for the light fixture?
Polaris taps.

You've confused me with 120. 120 is one leg of the split phase service. You could do 2 conductor cable, and service only the lights from this 120 volt run.

Or, if it's a multivoltage light (that will handle 240) use 2 conductor cable and feed it 240 volts.

Whats the question here? This is basic electrician knowledge...
 

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Hackenschmidt
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If you want to keep it simple and just throw a big wire at it, I'd figure on a 20A GFCI circuit with 15A receptacles at each light. The Southwire voltage drop calculator tells me I'd need #2 aluminum or #4 copper to limit the voltage drop to 5%. So if someone plugs in a hair dryer and styles their hair at that second light, they'll get nearly full power and heat.

The NEC doesn't hold you to voltage drop so if you want to design this for less than full load, there's nothing stopping you, and you could go smaller. Ten amps and 10% drop would get you down to #8 copper or #6 aluminum.

If you take out the receptacles, you might find that the LED drivers will tolerate a really big voltage drop and you could just run #12 UF and be fine.

You could stub up to an enclosure on the pole where you tap the big wire with normal size wire for the receptacle and fixture. You can use an outdoor connector, if all else fails there will be split bolts that will work.
 

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I have a customer with a 400amp service and a huge piece of land. He wants two LED pole lights put up. The first pole will be 385 feet away from the meter and the second will be 265 feet farther. How do I do this? I know voltage drop is an issue, but I don't quite understand it. Right now my plan is to run a three wire #4 from the meter to the first pole and put a 240v 30amp panel. Then run another three wire #4 to the second pole and put in a 240v 20a panel. I would separate neutrals and grounds at each panel and install a ground rod at each pole. Each panel would have a receptacle and Dusk to Dawn light. Does this work? OR do I have to plan for voltage drop from all the way back (650') at the meter for the second pole? Thanks! -John
How far is the utility XFMR from the meter and what size, type, free air/underground? You need to figure that into your calculation.


What is the load for lighting or any other loads to be connected at the poles?

Sent from my iPhone using Tapatalk
 

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Here we'd drop hand holes next to each pole, stub up into the pole, run UF up to the fixture and tap on to our run conductors with utility pedestal connectors or street light connectors and be done with it. Two LED's aren't gonna draw **** so you don't have to go nuts, if they really want receps figure in a conservative amount for that, if there's gonna be receps involved I'll try and keep the VD around 5'ish%.

I hate when there's a ton of stuff hanging off light poles, and I hate when people try and stuff a bunch of stuff in the pole hand hole too.
 

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I would run #4 copper stubbed up into the poles (assuming the poles have the large access cover at the base). Install GFCI receptacles on the pole and use polaris connectors or split bolts to go to #12 inside the pole were the covers are. Only thing mounted on the poles would be the box for the GFCI's.

If they don't have a large opening with a cover at the base I would install hand holes like Jlarson recommended.
 
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Are you wanting a 15A circuit at the end or are you just connecting lights? If just lights, what type?

Because I'm looking at all the #4 suggestions and thinking wtf?
 

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Are you wanting a 15A circuit at the end or are you just connecting lights? If just lights, what type?

Because I'm looking at all the #4 suggestions and thinking wtf?
OP did mention a receptacle at each panel(mounted on each pole). The #4 was to keep VD below 5% if they wanted proper power at the receptacle. Like mentioned before, if its only for the LED's they usually can handle a wider range of voltage without issue and #4 would not be needed. In CA I'm used to following Title 24 energy regulations and try and keep my VD low.
 
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I'd probably use #6 AL for that. 650' isn't much for two LED heads that are only going to have a minimal draw.

We're doing a street lighting project currently. If I remember right, on our longest run, I have #2 AL running 2700' for the 240v LED decorative poles. It's not the olden days with MH/HPS pole lights and serious power draws....you can go quite a ways with 240v LED.

It is also set up with a handhole adjacent to the pole base where we'll utilize direct burial rated Polaris connectors to splice onto the smaller pole wiring.
 

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Discussion Starter #15
Thank you all for the input! I don't know why it didn't think to run a 120 circuit. They're looking at a couple different led lights. They are all 120v and the biggest one is gonna be 300Watts. They want a receptacle to run some type of radio on the first pole. They're using wood poles. So, my plan now is to run a 120 circuit in 1/0 wire to the first pole. Put a big weather proof box at the first pole and use polaris taps to couple the 1/0 and attach to a #12 for a receptacle and a line for the LED. Then just go in 1/0 to the second pole and repeat the process with the box and no receptacle.
 

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Hackenschmidt
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It's a rich dudes HUGE piece of land. He's looking at these for the biggest. https://www.superiorlighting.com/content/vspfiles/spec_sheets/area-lights-specsheet.pdf
That spec sheet says those lights will run on 120V - 277V and even if they were both at the 650' pole you could use #6 UF and at 6A and 120V you'd have less than 3% voltage drop. I assume those specs have some tolerance, but how much? If your utility power is actually say 117V at the panel and you keep it to 3% voltage drop that's still 113V. Will they run perfectly on 113V? What are you going to do if they don't?

Now with a 240V circuit, you'd have less than 3A at less than 5% voltage drop with #14 UF and the lights would be perfectly fine. You have all kinds of margin for error there. If the lights don't function, it's sure not your fault.
 

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Hackenschmidt
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So what would you do if you wanted to supply the big lights with 240V and the receptacles with 120V?

I like the idea of using #6 UF here because it's reasonably easy to get and work with and would give decent power and voltage drop at the receptacles. Or maybe just go all the way and use the 1/0 Al. The real money is in digging the ditch not the wire you bury in there. Big project for a customer with a big budget, they will probably agree.

So maybe a three-wire 240/120V circuit would be a good way to go, with the lights tapped at 240V, the receptacle at the first pole tapped off L1-N and the receptacle at the second pole tapped off L2-N?

And, maybe a small 3R main lug panel as @bantar1000 suggested in the first place would be as good a way as any to go? You don't really need it if it's fed from a 15A or 20A GFCI breaker, but maybe it would be worth it because it makes the splices and taps simple and you have switches and resets at the poles. By the time you pay for polaris taps and an enclosure, maybe the panel is the most practical solution.
 

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