Service entry question

[kadoka]

My service entrance will be on a utility pole about 80 ft from my service breaker box located just inside the garage wall. My meter and main breaker will be on the utility pole. The cable will be undergound from there to the house. It will be a 200amp service. Two questions.

1. When the cable comes out of the ground and into the house, do I need a shut off switch outside before the main breaker panel or can it just go up and through the wall into the breaker panel?

2. What size and type of wire do I need for the underground feed?

thanks.
Bob

[steeve]

hi, i m not sure that it's code to put the meter and breaker on the pole...there should be min lenght between meter and entrance, is it a temporary service?...for the wire just call your local home depot center...or you could check out that site for inf... :)

http://ourworld.compuserve.com/homepages/boyce_smith/wiresize.htm

[bkrahmer]

Question 1 would be a good one for your utility. I don't think you'll need one, though. My meter box with main shutoff is 240' from my house, and I don't have another shutoff outside of the main breaker in the panel. Local codes could dictate something different, however.

2. Your local choices of SEU cable may be limited. 4/4/2 would certainly work. It's what I would use, although it may be a bit overkill...

[kadoka]

bkrahmer

Thanks. I am pretty sure you are correct. I spent some time checking around yesterday and it doesn't seem that I need another shut-off on the house. Better a little over kill on the wire size than to have to worry about the inspector.

I appreciate your help.

Bob

[roger g]

Hey steeve, In Alberta, I saw the metre and such on the pole near the road many times. First time I ever saw such a thing.

roger

[Vector]

I'm really not sure where bkrahmer got 4/4/2 as suitable for 200A service, it would be fine for 100A though.

Table 310.15(B)(6) says:

Copper of 2/0 or Aluminum of 4/0 for 200A

Aluminum is cheaper, but you have to know what you are doing when you install it or it can be a problem. Copper is much more forgiving.

Now, the real question.

Why locate the meter and main breaker on the pole? What's the driving force behind this? I can think of so many reasons against doing it that way, but none for.

[kadoka]

Vector

That is the way the power company does them here. We are out in the mountains on 4 acres. Saves having to have another utility pole put in also. Won't have to do a temp hookup for construction either. The permanent one will be already installed. Just need to run the undergound cable when the house is ready.

[roger g]

Hey Kadoka, where is "here"?
I wonder whether the utility company finds it a lot easier to read meters when it is so close to the road. My wife had a parttime job reading meters one time and the scary stories she tells would make most people NOT to read meters.
There is always a reason as to why things are done a certain way.

roger

[bkrahmer]

Vector, I think you may have taken my suggestion for 4/4/2 too literally. That's what they call 4/0-4/0-2/0 SEU around here (usually aluminum). I guess I should have been more clear and used the correct term.

[steeve]

aluminum wiring, is one thing i wouldn't use even on my car, and specialy not for service entrance, :shock: ther're fire hazards if you dont do it the right way. you have to use specific conectors for AL, etc, never mix AL / CU it makes a reaction... they tend to heat and with time break ... :roll:

[steeve]

bkrahmer,
hope you have a BIG pad lock on your main, i wouldn't want a stranger to pull the swith.... :lol:

My meter box with main shutoff is 240' from my house

[bkrahmer]

Steeve, have you priced out service entrance wire lately? I would have been looking at in excess of $1500 for copper compared to about $500 for Al. Secondly, if the wire is sized properly and you're not loading the wire to the max, and you properly use anti-oxidants, Al service entrance wire is not a fire hazard. If it was, it wouldn't be code-approved. Besides, the biggest electric load in my house will be the washer or maybe the stereo.

And no, I don't even have a lock on my meter base. I live in part of the country where you're likely to get shot messing with somebody's house like that.

My choices were to run my own wire after the entrance for about $3 per foot, and put it 240' away, or let the electric company do it for $7.50 per foot. I decided to keep the $1000.

[steeve]

bkrahmer, you're right, it's code...but not for me. it's comparable to tires, there's $25 and $200 ones....i just hope you wont have to change it one day...it's a long way home for $1500... :lol:

[Vector]

OK, around here I'd never heard anyone talk about 4-4-2, but 2-2-2 is very common, and it's 2, not 2/0. In retrospect, I should have realized what you meant because the neutral is a smaller number, not a larger one :)

Anyhow, Aluminum wiring can be safe, if everything is done right, as said above:

the wire is sized properly
properly use anti-oxidants

add

torqued correctly at the connections
the insulating jacket is not compromised in any way during burial

If you get so much as a nick through your insulation during burial, Aluminum wire will rot away at that point in a matter of months or just a couple years at most.

Do it right, and Al will save you a ton of money on the service though.

I'd never use Al wiring inside the house. Not that it can't be safe, but the cost benefits don't apply to smaller guage wires, but the hassles are the same.

If you look at the wire the utility company runs to your meter, it is almost certainly Aluminum.

As an aside, it's probably also much smaller than what you have to use by code. For instance, I have 3/0 copper from my meter to my main breaker for my 200A service (2/0 would be fine, but it was a very short run and the cost difference was negligable, so I went up one size). The wire run from the pole, underground, to my meter, is 2/0 Aluminum, which would be way too small for me to use by code. But the utilities play by a different set of rules. And it's still safe.

[Vector]

bkrahmer, you're right, it's code...but not for me. it's comparable to tires, there's $25 and $200 ones....i just hope you wont have to change it one day...it's a long way home for $1500... :lol:

That's one of the best arguments for trying as hard as possible to have your meter located at your building. The wire up to the meter is the property and responsibility of the utility, and if anything should happen to it (besides you physically damaging it by digging or something like that), they're the ones who have to deal with it.

I know that my utility (Xcel) charges by the foot to run underground service, but the cost is less than $4/ft, if I remember right (plus a base cost), and the wire can cost more than that, ignoring the trenching.

Of course, my run was only 20', so it was hardly a big issue regardless.

Regardless of all of this, you can bet that I would still have a "main" breaker in my panel, even if there was already a breaker at the pole. In the case of an emergency (fore for instance), I'd really prefer to be able to shut off power at the house, rather than having to run 80' (or 240') away.

[Vector]

bkrahmer, you're right, it's code...but not for me. it's comparable to tires, there's $25 and $200 ones....i just hope you wont have to change it one day...it's a long way home for $1500... :lol:

I'm sorry, but that's a bad analogy. There is no difference in safety, performance, or longevity with properly installed Aluminum wire vs. Copper.

Aluminum got a bad name from improperly terminated and sized interior wiring back in the '50s.

[bkrahmer]

Steeve, it's ironic that you are lecturing me about not using copper wiring. I remember a discussion awhile back when you were asking if you should use 2x4 framing for your exterior walls. :shock:
There are many, many things in my house over-code. But, I only overbuild when there is an advantage. Using an unverifiable theory of longevity is not a valid argument, IMO.

Aluminum got a bad name from improperly terminated and sized interior wiring back in the '50s.

Exactly. There should only be two possible points of failure in my Al wiring, and both are easily inspected. My SEU is run through conduit that I placed myself, and I watched the burial of it as well.

it's comparable to tires, there's $25 and $200 ones

That is also a very bad analogy, BTW, and here's why: $25 tires usually have 60-80k mile warrantees, and the $200 usually don't have any warranty.

If the cost difference is a few bucks, then splurge. A $1000 decision has to be made a bit more carefully.

[steeve]

sorry guys...That's what they call 4/0-4/0-2/0 SEU around here (usually aluminum). , but when it comes to safety money is no issue, and ill keep my end, spacialy for DIY...on this furum

for those who realy want to use AL, do it right...
http://inspect-ny.com/aluminum.htm[/quote]

[kadoka]

Roger

Here is the mountains of Colorado. The power line is actually located on the rear of my lot. It won't actually be any easier for the meter reader to get to than if it were on the house. Actually more difficult as it will be inside the fence for the ferocious Basset Hound. It s a remote area. I lived in the mountains outside of Albuquerque for a few years and meters and main breakers on a power pole were very common also.

Vector,

At a $1000 a pole to have service poles set, the price of wire doesn't look too bad and I won't have any overhead wires over my back yard. This way I only have to pay for one pole. To do an overhead directly to the house, I would have had to have a second pole set by the utility company.

[kadoka]

Steve

Thanks for the article.

[kadoka]

Got another related question.

What does "The reduction of feeder wire, URD (underground rated feeder wire) shall not be allowed. The reduction of neutrals for service feeders shall not be allowed"?

[steeve]

kadoka, dont know about your area, but there's companys that cary service poles and you could set them your self vs paying utility company, there's money to be save there.

[kadoka]

Actually the utility company was very reasonable. For a pole and transformer it was only $800.00. They give you a big discount if you are building a house you are going to live in 12 months a year. A lot of small homes and cabins up there that people just use on the weekends.

[bkrahmer]

Actually, most (smart) companies don't use meter readers anymore, at least in low-density areas. They have these things called 'turtles' that transmit the meter readings back over the lines back to a computer that automates their billing.

[Vector]

Got another related question.

What does "The reduction of feeder wire, URD (underground rated feeder wire) shall not be allowed. The reduction of neutrals for service feeders shall not be allowed"?

In some cases the NEC allows for use of smaller wires, if the wire will be in a cooler location (cooler wires can handle more current). Your utility doesn't allow that. So 2/0 Copper or 4/0 Aluminum is what you need.

The second part, the reduction of the neutral, is very common, and in fact is what was being suggested with the 4/0-4/0-2/0 service wire. Because of the way that standard 1-phase 120/240V, 200A service works, the neutral wire will never carry more than 100A of current. In many (maybe even most) cases you are allowed to use a smaller conductor for the neutral as a result. Your utility also isn't allowing that.

So you would need 2/0 copper for all three conductors or 4/0 aluminum for all three.

[kadoka]

Vector

Thanks for the explaination.

[kadoka]

Just when I think I have this all straight something else pops up. I will be mounting just a main breaker panel on the pole. The rest of the breakers will be in a panel in the garage. I have to mount some GFCI outlets on the side of the main box for temp power during contruction. Will I need a breaker for them or can I just wire them directly to the switched side of the 200amp main breaker? That doesn't sound right to me but there is no place to mount another breaker in the panel.

[Vector]

You will need a temporary panel. Exterior rated too.

Get one the same brand and line as your permanent panel will be, so you can re-use the breakers. Cost should be fairly minimal, I think mine was about $30.

[kadoka]

Thanks Vector.

[bkrahmer]

What I did for temp power was to get a meter base that has a main breaker as well as a place for 4 more breakers in it. Then, I ran my gfci outlet off a 20 amp breaker right there.

I ditched that temporary last night, actually. Finally got an outlet installed in the house. Yah.

[steeve]

kadoka,

if you have a place in your panel for a breaker you can use a gfci breaker instead of an outlet, the hole circuit will be protected, the're a bit expensive, but you can reuse it later on...swiming pool, kitchen,etc... :wink:

[kadoka]

Steeve

I have some GFCI breakers but there is just no place in the main box to install a breaker. It is just holds the 200amp main. I am going to get just a small box and mount in on the side of the main box for the GFCI breaker.

I had this all planned out then the power company wanted the main breaker on the pole. Threw a wrench into my design. Oh well. What is one more small breaker box in the price of the house.

[steeve]

Threw a wrench into my design

and it's only the begining... :lol: