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Beam Me Up Scotty
Elechicken
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I lit up an entire car dealership parking lot with 3x 150W LED floods. The pole won't be tall enough to utilize the light from a 300W fixture. Or, it will blind anyone coming down the driveway.

But hey, don't argue with a rich customer.
The real question here is how tall is the pole.

Rich customer? Heck, it could be a 100' tall pole for all we know...
 

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Discussion Starter #22
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.
If I Do go with 240V and put in panels. I don't understand where voltage drop takes place. The southwire VD calculator says, at 385 feet I can run my first 240V panel on #4. When I'm calculating the SECOND panel, do I calculate the VD from the new breaker and the remaining 265 feet, which the southwire VD calculator still says #4. OR does the second panel have to be calculated at 650 from the meter, even though there is a breaker for the second panel 265 feet away?

If I can do that, then mobile home feeder 2-2-2-4 is cheap ($1.06) and easily accessible!
 

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Hackenschmidt
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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.
I was on hold for over two hours waiting for a consultation with Professor Hackworth, chairman of the Department of Code Compliance and Professional Wrestling at New Jersey Academy of Applied Science. On behalf of the Academy Professor Hackworth extends his warmest regards to the membership and management here.

Noe that 250.32 requires a grounding electrode when you extend a branch circuit or feeder to a building or structure.

A light pole is a structure, there is an exception for light poles without disconnects but with a panel that of course would not apply, the breakers would be disconnects.

If you use a panel, the breaker in the house is not the last overprotection device in the circuit so the supply to the pole is a feeder, so the 250.32 exception for a single branch circuit would not apply. So you'd need a grounding electrode.

Now since you're trenching a grounding electrode is no big deal but at that point it's way more trouble and expense than an enclosure for taps.

As usual the conversation with Professor Hackworth was civilized, dignified, cordial and cerebral. Except he thinks that Andre the Giant is overrated and not even a contender for Greatest of All Time, which only someone with their brains in their ass would say.
 

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Hackenschmidt
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If I Do go with 240V and put in panels. I don't understand where voltage drop takes place. The southwire VD calculator says, at 385 feet I can run my first 240V panel on #4. When I'm calculating the SECOND panel, do I calculate the VD from the new breaker and the remaining 265 feet, which the southwire VD calculator still says #4. OR does the second panel have to be calculated at 650 from the meter, even though there is a breaker for the second panel 265 feet away?

If I can do that, then mobile home feeder 2-2-2-4 is cheap ($1.06) and easily accessible!
Voltage drop occurs in the wire due to the resistance of the wire. The wire feeding pole 1 is in SERIES with the wire feeding pole 2. That makes the voltage drop calculation kind of difficult. Because voltage drop is dependent on load, and the load to both panel 1 and panel 2 is on the wires feeding panel 1, the voltage drop to panel 1 will be calculated with BOTH loads.

The voltage drop at panel 2 is cumulative - you have to start with the already reduced voltage present at panel 1, and do the calculation there.

And plus the CURRENT at panel 2 will depend on the voltage drop at panel 1, so the calculation is not striaghtforward.

At these distances, I'd rather not attempt the mathematics to calculate it super tight so I can maybe (maybe) run a slightly smaller wire from pole 1 to pole 2. Just not worth it. I'd just do the calculation as if all of the load is at 650' which will cover you for sure.
 

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Hackenschmidt
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@bantar1000
You say rich customer, don't try to save them money use what you need to do the job right.
As @splatz said if it don't work at 650' your screwed for trying to save them money, wire is cheap. I'd also propose a second conduit for a camera or other gadget, since the ditch is open.
You lose money for saving them don't make business sense.
 

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Band Member
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I was on hold for over two hours waiting for a consultation with Professor Hackworth, chairman of the Department of Code Compliance and Professional Wrestling at New Jersey Academy of Applied Science. On behalf of the Academy Professor Hackworth extends his warmest regards to the membership and management here.
Next time you talk to him, tell him I think of him everytime I wafflestomp in the shower :censored:
 
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152049
 

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Technically if its just the lights (300w each) its 5 amps at 385' then 2.5 amps at 265'

so using 10g at 385'
Voltage drop: 3.85
Voltage drop percentage: 3.20%
Voltage at the end: 116.15

then 265'

(starting voltage 116)
Voltage drop: 1.32
Voltage drop percentage: 1.14%
Voltage at the end: 114.68

total vd 120-114.5 = about 5.5v

5% drop on 120 is 6v so 10g would do if it was just for the lights..
 

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I think most people(and my self) that recommended 4ga was for the receptacles to work properly not the lights.
 

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I would have no problem using hand holes and 2-2-2-4 aluminum as its cheap and gives lots of options. I would also not have a problem using a smaller gauge to make life easier for the first 20' which gives you lots of options to the first hand hole. (really depends on panel fill). 20amp dp breaker means you don't need breakers in the field the lug excepts a 8g wire so 20' feet of 8 copper would make life easier.

As long as you add the total load per section and change the voltage in the calculator as you calculate the sections it should be fine.
 
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