Originally Posted By: phinsperger This post was automatically imported from our archived forum.
The overhead service drop can use smaller gauge wire because it is in free air and can disipate heat much better than the ones running down inside your service mast.
Originally Posted By: Greg Fretwell This post was automatically imported from our archived forum.
The power company is regulated by the NESC so it is not exactly “anything they want to do”.
The main difference is their drop is single conductors in free air, not wires in a raceway or cable so the ampacity is higher. Since the I2R losses are on their side of the meter it is up to them how hard they want to push it.
Most 200a services seldom actually run more than 60-70a for any length of time.
Originally Posted By: jtedesco This post was automatically imported from our archived forum.
The drip loops are not correct, they are to be made in the service entrance conductors!
Drip loops shall be formed on individual conductors. To prevent the entrance of moisture, service-entrance conductors shall be connected to the service-drop conductors either (1) below the level of the service head or (2) below the level of the termination of the service-entrance cable sheath
Originally Posted By: bbadger This post was automatically imported from our archived forum.
Joe I do not see where it says the drip loops can not be on the utility conductors.
Quote:
230.54(F) Drip Loops. Drip loops shall be formed on individual conductors. To prevent the entrance of moisture, service-entrance conductors shall be connected to the service-drop conductors either (1) below the level of the service head or (2) below the level of the termination of the service-entrance cable sheath.
All I see is below the service head or SE cable sheath.
Russell Do not concern yourself with the power company wiring they have a lot of historical data that they base conductor sizes on. I agree with the others that they follow different rules, most follow the NESC.
I go to a forum that has a power company engineer on it and he claims they typically figure the real load will be 50% of what the NEC calculated load is.
If you tried to figure out the transformer sizes they use you would really be surprised. 
-- Bob Badger
Electrical Construction & Maintenance
Moderator at ECN
Originally Posted By: Russell Frame This post was automatically imported from our archived forum.
Quote:
Russell Do not concern yourself with the power company wiring they have a lot of historical data that they base conductor sizes on. I agree with the others that they follow different rules, most follow the NESC.
I go to a forum that has a power company engineer on it and he claims they typically figure the real load will be 50% of what the NEC calculated load is.
If you tried to figure out the transformer sizes they use you would really be surprised. 
Thanks Bob. The installers didn't have my faith due to some general comments and observations they made earlier in this process and when I saw the small conductors I got concerned that they were just "throwing up what they had on the truck". I've since talked to some engineers about this and they concur with the comments made above that the Power Co's definitely have different rules about this stuff. As for the drip loop comment, I dont see how Joe is reading it the way he is reading it, but that again was the Power Co's work so I will defer to their expertise.
Now I can enjoy the fact that my new house is alive!
Originally Posted By: jtedesco This post was automatically imported from our archived forum.
Bob: and Russell:
The Section 230.54(F) I mentioned is in Part IV. Service-Entrance Conductors, and the "drip loop" is supposed to be in the service entrance conductors. 
Quote:
As for the drip loop comment, I dont see how Joe is reading it the way he is reading it, but that again was the Power Co's work so I will defer to their expertise.
Originally Posted By: Greg Fretwell This post was automatically imported from our archived forum.
You are right about one thing. They do use what they have on the truck but that is the drop for 200a service, no matter whether you actually have 200, 150 or 100. That is why they don’t swap out the drop on most service upgrades if it is triplex. It is also why they wince at greater than 200a and you still may get the same drop as your neighbor.
The only time I would question a drop size on 200a if it is the old 3 strand separate conductor thing. The twisted “triplex” seems to be the same for everyone.
Originally Posted By: Greg Fretwell This post was automatically imported from our archived forum.
lfranklin wrote:
Quote:
The only time I would question a drop size on 200a if it is the old 3 strand separate conductor thing.
Are you talking about the old 60 amp service
Yep I would think that is what a 60a would use. We had 100a in the 50s and that was it. By sometime in the 70s they had started using triplex and I have never seen any that wouldn't go 200a ... at least as far as the utility said. When I put in my 200a panel here in Fla the only question the engineer at FPL asked me was did I have triplex.
The customer owns everything from the "service point" where the drip loop and crimps are. That I did have to upgrade.
