Dumb service lateral questions

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mark32

mark32

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Currently in NJ
A gentleman at work asked me what size and type of wire he would need to feed (Underground) a 200a panel 1000' away from the transformer! When I asked what his electrician recommended his response was to call the poco, which I agreed with of course. Gentleman says the poco told him 4/0 al should be okay but that seems too small. Now here are my questions, first, how do most poco's size their feeders? Second, what type of wire is used for underground feeds?
 
mark32 said:
A gentleman at work asked me what size and type of wire he would need to feed (Underground) a 200a panel 1000' away from the transformer! When I asked what his electrician recommended his response was to call the poco, which I agreed with of course. Gentleman says the poco told him 4/0 al should be okay but that seems too small. Now here are my questions, first, how do most poco's size their feeders? Second, what type of wire is used for underground feeds?
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In order to answer your question you need to provide the load in amps and the voltage? Is this a residence?
 
Utilities are not subject to NEC requirements, so they don't follow NEC for sizing rules. Second, the type of wire will be determined by the type of installation, direct burial conductors, PVC, etc. I would believe that USE would be the basic type for this install. The distance away would make me think the voltage drop is going to play a big factor in the size of the wire and they are going to end up at 350 MCM AL (I didn't do the VD calc, just estimating).
 
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Good morning, thanks for the responses. I asked the gentleman what the calculated load is but he didn't know, as far as voltage I'm assuming 240v and this is a residence. With such a long run I'm figuring direct burial would be the way to go instead of piping it. Basically the guy just wanted what to know what wire to use so I can give him a price on it (the wire) but neither his electrician or poco gave him much to go on. He needs to have one of the other parties involve to come up with a more accurate estimate on loads, vd, etc, I'm just the consultant/sales person in this scenario but I am curious as to how the feeder would be determined in such a a case.
 
mark32 said:
I'm just the consultant/sales person in this scenario but I am curious as to how the feeder would be determined in such a a case.
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the electrician doing the work should do a load calculation, and then use a voltage drop calculation, since you are just in the position to sell the customer material, I would not get involved in giving advice on what size wire to buy, I would just supply them with what they say they need....
 
Assuming the max load on the panel is indeed 200A, and using a VD or 3% between transformer and panel, I come up with a rough estimate of 750MCM feeder cable, or parallel 350MCM's
 
You won't be able to size the wire without knowing the expected load, but as the previous post shows the wire size will be quite large if you don't want A LOT of voltage drop. 1000' is a very, very long way for such a low voltage.
 
mark32 said:
Basically the guy just wanted what to know what wire to use so I can give him a price on it (the wire) but neither his electrician or poco gave him much to go on.
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Humm, is he price checking the cost to provide the service or is this something he is going to buy. If he is buying it, then it would be reasonable to assume PoCo is not installing it.
 
hardworkingstiff said:
Humm, is he price checking the cost to provide the service or is this something he is going to buy. If he is buying it, then it would be reasonable to assume PoCo is not installing it.
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I suspect this might be an exercise to see how spendy it would be to supply at 240V vs. pay the utility to bring the tranny closer...

480V step up/down has been discussed may times as an option...

Could/would a utility supply a single phase 480V service? I would assume not since that odd-ball size would probably be an additional cost that would outweigh a sparate 240-480V tranny...
 
drbond24 said:
You won't be able to size the wire without knowing the expected load, but as the previous post shows the wire size will be quite large if you don't want A LOT of voltage drop. 1000' is a very, very long way for such a low voltage.
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DR,
At $5 per foot,
and 3000',
that would be $15,000,
plus a team of mules to install it.

You are right, this is a veeeerrrry long pull.
He should, at the least,
consider the higher voltage alternative.

glene77is
 
For those whom are interested, I finally spoke with the customer after calling and missing each other for almost a week. It turns out that the poco IS planning on running the feeders at 5kv and then of course drop a transformer much less than the 1000' from his house he initially told me. I called my contact at Southwire but they told me they cannot sell or quote a price for such a cable because their contract with Home Depot is only for residential level products, so I had to send him to another supply house. At least I got a chance to research/learn about cables I've never had the chance to use before, that being USE and URD. Is it true URD is USE cables in a 3 or more wire configuration?
 
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mark32 said:
For those whom are interested, I finally spoke with the customer after calling and missing each other for almost a week. It turns out that the poco IS planning on running the feeders at 5kv and then of course drop a transformer much less than the 1000' from his house he initially told me.
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Glad to hear it.

mark32 said:
Is it true URD is USE cables in a 3 or more wire configuration?
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I have no idea. :)
 
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