Overkill???

Question

I'm switching from a 100 to a 200 amp service. I'm going to lay new cable from the meter, 185 feet, underground, to the entrance of the house. I have a retired city electrical inspector (I'm out in the county where no inspections are required) that is going to do the connections and some inside work. He told me the other day that I needed to use #2 copper cable unless it was over 200 feet and then would have to go to #3 (or vice versa -- that's not the question) in schedule 80 EIGHTY!!! pipe. The question is, why copper instead of aluminum and why in the world he call for schedule 80??? I have cattle trucks, loaded 18 wheelers, run over schedule

40 all day long and never have a crack. The original wire is not in any pipe at all.

If left to my own devices I'd just run 185 feet of whatever size cable required with no pipe. Is this guy doing some overkill here just to be on the safe side?

RBM · Accepted Answer

Ask him what he's basing this on. Ask him how he's figuring his wire size as well

"Blattus Sl · Answer

Use the calculator at the bottom of this web page and see if you need copper or aluminum.   pipe is up to you and weather or not the wire is made to be buried with or without.

"Blattus Sl · Answer

Here is another handy little chart.

John Grabowski · Answer

Will there be a main circuit breaker protecting this service feeder from the meter to the house? In NJ one power company requires that the underground conduit from the pole to the meter be schedule 80. After the meter if there is fuse or circuit breaker protection you can change to cable or schedule

If you are going under a driveway the conduit should be at least 24" deep.

For a 200 amp service (310.15(B)(6) 2/0 copper or 4/0 aluminum is required. Considering the distance of your service you will probably be better off with an oversized copper feed to compensate for voltage drop.

marson · Answer

sounds like overkill to me.

Pat · Answer

We just put in Schedule 80 for our 600 amp service. Phone went in schedule 40 (6" for no apparent reason). Cable went down as a cable/ conduit combo wire. Then, under our driveway they required 6" of concrete on top of the conduit. Personally, I think the concrete was overkill.

Then they required conduit to within 3" of the transformer on the pole.

Edwin Pawlowski · Answer

Copper that size is probably $2.50 a foot or soAs for the schedule 80, if he is talking steel, he is nuts.  If he is talking pvc, maybe.  Code would not allow plain wire unless it is made for burial.

JC · Answer

Thanks to all for the responses. I have the 2005 NEC and some parts of it seem to be typical governmental gobbeldy goop. For instance, on page 70-140, right hand column #3 it says "Bare or Covered Conductors. Where bare or covered conductors are used with insulated conductors, their allowable ampacities shall be limited to those permitted for the adjacent insulated conductors." Huh? What other type of conductors are there besides "bare" or "covered"?

Overkill???

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