Overhead Medium Voltage Design

Desert Sparky

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Location
Desert
Occupation
Electrical Engineer
I've been tasked with putting together a rough estimate for a medium voltage overhead line. All my design experience is from the utility source down, so this foray into the medium voltage world is new to me, and I'm hoping someone here can provide me a little guidance on determining what this installation will look like. Below are my parameters:

I need to span about 800'-1000' total from the source to my building, where we'll be feeding a pad mount transformer.
Overhead line will be 6.9 KV, 3 conductor.
This will be installed on a large industrial site, so the span is pretty much clear (no buildings or homes in the vicinity of the line).

Is there a rule of thumb that can help me roughly determine pole span, pole heights, type of pole, etc.? What about conductor size/type?
 
This is helpful, thank you. I'm just looking for a quick and dirty guide to put together a rough estimate of what the installation might look like, i.e. how many and what height poles will I need, what type of poles (wood vs steel), what size and type of conductor, etc. based off of the voltage and length of overhead line.
 
You'll likely want to use ACSR. You can look up a ACSR datasheet for ampacities to give you a rough size based on how much current this is delivering. Ballpark 200ft between poles. That'll get you close. Usually our poles for something like this are 45-50ft total length, with about 5ft buried giving 40-45ft of exposed height. This sometimes will increase (50-60ft length) over crossing depend on sagging clearances. This is very rough and generic.
 
You'll likely want to use ACSR. You can look up a ACSR datasheet for ampacities to give you a rough size based on how much current this is delivering. Ballpark 200ft between poles. That'll get you close. Usually our poles for something like this are 45-50ft total length, with about 5ft buried giving 40-45ft of exposed height. This sometimes will increase (50-60ft length) over crossing depend on sagging clearances. This is very rough and generic.
This was very helpful, thank you very much. I was assuming 150-200 ft between, so I was not too far off.
 
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