6AWG copper for service entrance conductors on single family home?

[jaylectricity]

PVC weatherhead and riser had broken during storm. When I went to replace it I found #6 from the service drop to the meter socket. From meter to main disconnect is #4 SEU. Main breaker is 100A.

The article says the minimum breaker is 100A for a single-family dwelling, but is it possible that it was legal to use #6 based on the load calculation for the home?

 

[peter d]

Nothing in the NEC would allow this, but from a practical standpoint I don't see the hazard, especially in a small, all gas home.

 

[Martin B]

It's been a while since I've done a residential service but I would agree, the conductors should have been #4.

 

[peter d]

PVC weatherhead and riser had broken during storm. When I went to replace it I found #6 from the service drop to the meter socket. From meter to main disconnect is #4 SEU. Main breaker is 100A.

Copper SEU?

 

[jaggedben]

When was the 100A minimum for single family homes instituted?

At one point 6awg cu service conductors would not have been a violation, but that would have been when a 60A service was not a violation. My guess is someone upgraded everything load side of the meter at some point, but shied away from upgrading the service conductors like they should have.

 

[Martin B]

When was the 100A minimum for single family homes instituted?

At one point 6awg cu service conductors would not have been a violation, but that would have been when a 60A service was not a violation. My guess is someone upgraded everything load side of the meter at some point, but shied away from upgrading the service conductors like they should have.

Good point. I have heard of people cutting the tag and pulling the meter and doing a DIY service upgrade. In that case the risers would still be hot so I can see why they would still be #6 cu

 

[user 100]

When was the 100A minimum for single family homes instituted?

At one point 6awg cu service conductors would not have been a violation, but that would have been when a 60A service was not a violation. My guess is someone upgraded everything load side of the meter at some point, but shied away from upgrading the service conductors like they should have.

I think someone had mentioned before that the 100 amp minimum came about in either the 1959 or 1962 NEC(?)
I thought too this may be an older installation but then there is the pvc presence- unless they recycled the old conductors too.

 

[peter d]

This sounds like a classic "use what's in the truck at Friday at 3:00 PM".

 

[Martin B]

I think someone had mentioned before that the 100 amp minimum came about in either the 1959 or 1962 NEC(?)
I thought too this may be an older installation but then there is the pvc presence- unless they recycled the old conductors too.

The O.P. did mention that the weatherhead and riser where PVC, :slaphead:

I'm surprised that this would have passed an inspection though.

 

[user 100]

The O.P. did mention that the weatherhead and riser where PVC, :slaphead:

I'm surprised that this would have passed an inspection though.

Possible that guy may have pulled what Peter d said above and/or ahj made an exception for the #6.

Also likely is the old wh/riser or entire service getting replaced by a hack/side jobber- in this case, no inspection.:happyyes:

 

[chris1971]

PVC weatherhead and riser had broken during storm. When I went to replace it I found #6 from the service drop to the meter socket. From meter to main disconnect is #4 SEU. Main breaker is 100A.

The article says the minimum breaker is 100A for a single-family dwelling, but is it possible that it was legal to use #6 based on the load calculation for the home?

No.

 

[ritelec]

Nec 1987

Overhead drop conductors
230.23b
Underground service lateral conductors
23.31

Minimum size
The conductors shall not be smaller than No 8 copper or No 6 aluminum or copper clad aluminum.

Ex. Limited single branch circuit for water heater and alike. 12 cu 10 al



Service entrance conductors size and rating
230.42 b1

Ungrounded conductors shall have an ampacity of not less than 100 amp for 3 wire one family dwellings with six or more 2 wire branch circuits.

3. 60 amp all others.


Looks to me 60 was allowed if you had under 6 circuits.

Either way.

Looks like 60 was good for line side if meter at 100 amp

 

[growler]

At one point 6awg cu service conductors would not have been a violation, but that would have been when a 60A service was not a violation. My guess is someone upgraded everything load side of the meter at some point, but shied away from upgrading the service conductors like they should have.

That would be my guess also. When they flip houses they don't like to spend a lot of money doing things right.

They can pull an old 60 amp fuse panel and install a 100 amp breaker panel for very little money because they normally won't get an electrician or permit. They need the 100 amp panel to qualify for certain types of loans (FHA).

 

[kwired]

That would be my guess also. When they flip houses they don't like to spend a lot of money doing things right.

They can pull an old 60 amp fuse panel and install a 100 amp breaker panel for very little money because they normally won't get an electrician or permit. They need the 100 amp panel to qualify for certain types of loans (FHA).

Correct, and those that inspect for those loans are not real electrical inspectors. Sad thing is they can verify some punch list items exist but can not verify just how safe they may be.

I've seen 200 amp service panel supplied by old #6 SE cable a few times. Some cases the load just wasn't there to be too concerned, but at same time is easy for less or non qualified to add more load without ever knowing they created another problem.

 

[jaylectricity]

That's what I thought. Anyway looks like her "repair weatherhead" job just turned into a replace the meter, service conductors, and add ground rods job. The meter is pretty rusty, I don't think I could even get the conductors out of it with out damaging the lugs.

Nobody living there now, house for sale so I felt comfortable leaving it like that until she gets back in town.