Installing 120-volt Receptacles on a Lighting Pole

[hbendillo]

Here is my challenge:

I am lighting a roadway in a park that is about 4500 feet long or so. It is a main road in a sports complex. The owner wants to have a 120-volt duplex receptacle installed on each pole to power decoractive lighting or some special signage with lighting. I allowed for about 1.5 amps per pole which which I think is generous and with the lengths of the wiring runs say from a single point the wires sizes due to voltage drop are quite large. So, we have to set up multiple distributions points along the road with multiple circuits to feed these receptacles. Gets kind of expensive.

Has anybody done anything like this? My thoughts were since we are feeding the lighting on the road with 480-volt circuits, there has got to be a way of tapping that circuit to a small step-down tranformer to feed the receptacle. But where does that happen? Not inside the pole or the fixture head. How about a special pole base with a wiring compartment? I guess we could set a small below or above ground vault near each pole. I am just looking for different solutions for the problem. If you have any product or wiring solutions for this I would appreciate some input.

By the way. The owner wants the receptacles mounted in the upper portion of the pole. so we have to provision the pole for that. Can't mount the receptacle at the base of the pole.

 

[iwire]

There is no way to do this without spending tons of money.

Yes you can do transformers at each pole, they can hang on the outside of the pole down low, but ugly.

Or you could use a larger transformer on each few poles and run the 120 from there for a few poles.

I have done jobs where a large enclosure was cast into each concrete base and transformers were located inside.

Or you can just run huge conductors to a hand hole beside each pole and tap small conductors from there into each pole.

All ways are expensive.

 

[broadgage]

A somwhat similar question was recently asked in the lighting forum.

I cant recomend a transformer at each pole, apart from the costs of all these transformers, remember that the customer will be paying forever for the iron losses in each transformer.

Consider either a 120/240 volt MWBC with massive cable sizes and a fused disconnect at each pole, or a 120/208 volt 3 phase 4 wire system.
From where is the power to be obtained ? feeding from the middle of the run, or from both ends will a lot easier than from one end only.

If power is only obtainable at one end, then one option might to feed only the nearest one third of the run at 120/240 or 120/208.
Then run a 480 volt or even an MV feed to a point two thirds of the way along, at which point instal a single large transformer to supply the rest.

Unless in a remote place, I would expect that several utility services, each for a part of the route might be a better option.

 

[mgookin]

Is there a photocontrol at each luminaire or is there a contactor per 35 or so luminaires? If they want the decorations powered up all day long when the lights are off, you'll have to consider that. You might even have a 240V line inside the contactor.

And if they only want to power up decorations for a part of the year, you may want to put a manual switch on the xfrmr that can be switched by the decoration installer. It will help keep the bill down and make the equipment last longer. Last thing they want is to set up all of their seasonal decorations only to find that a dozen xfrmr's died over the summer.

And that's a metered service? If not, the local electric utility is going to take issue with the lease light rate on those lights.

Advice to you or the owner: If in a high wind region, have a structural engineer take a look at the added loading on the pole.