Do I need to downgrade my main breaker?

[729Zoom]

When I moved into my house 42 years ago, there was already a 100 amp panel with a 100 amp main breaker but I recently found out that the service wire to my house and all my neighbors (who also have 100 amp min panels) is a #8 aluminum, which is only rated for 40 amps! I checked my historical usage as far back as I could on the utility site and bought an emporium energy monitor and found I have never pulled more than 30 amps at one time and, most of the time, I am pulling only 10-20 amps total. I think because I have all gas appliances, just two of us and we don't use a lot. So, it seems the #8 is more than enough.

BUT, we recently had to replace the panel when one of the bus bars went bad and we lost power. Our electrician replaced it with one that would let us get solar in the future without having to redo it. But it has a 200 amp breaker and I was thinking he should have put in a 100 amp breaker like I had before. I read that downgrading breakers is not uncommon. But now that this is already done and the utility company has already come and locked the meter, we would have to have them out to do that again to either downgrade the breaker or ask for a service upgrade, which we don't really need and hate to pay for that.

My thinking is if the service wire was undersized for the 100 amp panel and breaker we had and it never had issues over 42+ years, that a 200 amp breaker won't make any difference? And I should just keep it in case we do go to solar in the future? But, I wanted to get input from others. thanks.

 

[roger]

We will allow this for advice and disscussion

 

[Seven-Delta-FortyOne]

The POCO's wiring on the line side of the meter is not covered by the NEC.

It's their concern if they believe the existing wiring to be undersized. Their wiring sizes are often very different than what we would be allowed under the NEC.

That being said, any panel change out in my area would require both an Electrical Permit from the AHJ, and, for anything other than a "like-for-like" panel swap, which PG&E has a VERY narrow definition of, would also require an engineering review from the POCO. Certainly an upgraded panel would have triggered that in my area.

Was any of this done?

 

[729Zoom]

The POCO's wiring on the line side of the meter is not covered by the NEC.

It's their concern if they believe the existing wiring to be undersized. Their wiring sizes are often very different than what we would be allowed under the NEC.

That being said, any panel change out in my area would require both an Electrical Permit from the AHJ, and, for anything other than a "like-for-like" panel swap, which PG&E has a VERY narrow definition of, would also require an engineering review from the POCO. Certainly an upgraded panel would have triggered that in my area.

Was any of this done?

It was done as repair with the utility company and they didn't question anything. They sent out someone to look at the overhead and they removed the meter for the repair and then put the meter back on. This is just a question I had when I accidentally stumbled upon an article and that got me to wonder what size wire we had from the pole, etc. I assumed we had a wire for at least 100 amps since the panel was 100 amps and was here 42 years ago when I moved in. and that made me wonder if that is what caused the bus bar to go bad but when I looked at the usasge and got the emporia monitor, I found that we never draw more than 30 amps -40 amps max (and that is RARE and for brief periods) but 99% of the time we are drawing 20-30 amps. I am also getting confusing information from electricians. One says don't worry and another says it should be downgraded (and he will do it and charge me, of course) and I don't want to spend money or time if not needed so wanted more opinions.
Also, one more thing. The electrician who claims I need to downgrade (and what prompted me to come and get more opinions) claims it is a safety issue. He says that if the breaker doesn't know to trip if the service wire is overloaded, it could cause a fire. But, as I said before, if the service wire was undersized for our 100 amp panel and breaker, what would be the difference? Maybe the utility company knows our usage and why the don't change them? Could that be it?

 

[roger]

Nothing to worry about, the POCO will do what they need to do, they have had a lot of experience.

 

[LarryFine]

My guess is the house originally had a 60a service, probably fused, and upgraded to 100aw/out permit.

 

[junkhound]

Our house is a 200 A service. Poco feeder overhead is @2 aluminum. I have pulled close to 200 A on occasion in short spurst of overlapping loads: heat pump running (24A), DW with 2 dryers running @22A each) , me welding going on (50+ amps), Some pies in the oven (35 A), and son using 4000psi electric pressure washer (55A). Another 20+A if HW heater happens to come on. Overhead #2 auminum never a problem except for voltage drop.

 

[729Zoom]

My guess is the house originally had a 60a service, probably fused, and upgraded to 100aw/out permit.

View attachment 2573142

I think that is the case but the entire neighborhood, for the most part, has the same size wire. I am wondering if they did permits back in the late 50s or 60s when I think it might have been done.

 

[petersonra]

The wire is outside in free air so it gets cooled better than if it is in the walls of your house.the utility is very good at sizing it's equipment. I would not get real excited about it unless you need to add load.

 

[wwhitney]

Per the NEC, there's a certain point on the electrical supply to your house called the service point. The utility is responsible for the wire on the utility side of the service point; if they use #6 Al for 200A there, it's on them, and if it burns up, they'll replace it. On an overhead service, often the service point is where the wires from the pole are spliced to the wires coming down the side of your house, near the top of the conduit riser called the weatherhead.

On the house side of the service point, your responsibility begins, and the NEC sizing rules apply. And one of those rules is that if a single breaker shuts off all the power to your house, the size of your conductors needs to match the size of that breaker. So if that breaker is 200A, that's fine, as long as the wires from the service point to that breaker are rated for 200A.

If you have #6 Al (under utility control) -- service point -- 100A conductors under the NEC -- 200A breaker, that's an NEC problem that needs to be fixed, either by downsizing the breaker, or upsizing the conductors from the service point to the breaker.

Note that with an underground electrical service that rises directly into a combination meter / main breaker piece of equipment, it is possible that the service point is at the utility side of that meter, and all the conductors between the service point and the main breaker are part of the factory assembled meter / main breaker equipment. In which case if that equipment is rated 200A, the size of the conductors landing on the utility side of the meter is not subject to the NEC.

In all cases, if you replaced 100A rated equipment with 200A rated equipment with a 200A main breaker, the utility needs to be notified of that, and may have their own procedures triggered by that upgrade.

Cheers, Wayne

 

[729Zoom]

I think that is the case but the entire neighborhood, for the most part, has the same size wire. I am wondering if they did permits back in the late 50s or 60s when I think it might have been done.

I think that is the case but the entire neighborhood, for the most part, has the same size wire. I am wondering if they did permits back in the late 50s or 60s when I think it might have been done.

My guess is the house originally had a 60a service, probably fused, and upgraded to 100aw/out permit.

View attachment 2573142

The house was built in 1948 and I think 100 amp panels with circuit breakers were being used by then? Do you know? If so, I think the panel that I had before came with the house now. There was an addition that was done in 1951 and I know it was permitted because 25 years ago, I requested all the paperwork related to the house from the local agency because I couldn't find anything in the online system. I just found the file and nothing in the paperwork is for the electrical for either the 1951 addition or the 1948 original build so I have no idea. It seemed odd to me that the utility company uses such little wires even for 100 amps, much less 200 amps. But, perhaps they make their changes based on their records of what the customer draws. I have an emporia vue monitor and have been tracking my usage since yesterday and my total usage has not exceeded 8 amps for even one minute. I have a small home with all gas appliances but still expected to see at least 20 amps. and today I ran my window AC most of the day.

 

[729Zoom]

Per the NEC, there's a certain point on the electrical supply to your house called the service point. The utility is responsible for the wire on the utility side of the service point; if they use #6 Al for 200A there, it's on them, and if it burns up, they'll replace it. On an overhead service, often the service point is where the wires from the pole are spliced to the wires coming down the side of your house, near the top of the conduit riser called the weatherhead.

On the house side of the service point, your responsibility begins, and the NEC sizing rules apply. And one of those rules is that if a single breaker shuts off all the power to your house, the size of your conductors needs to match the size of that breaker. So if that breaker is 200A, that's fine, as long as the wires from the service point to that breaker are rated for 200A.

If you have #6 Al (under utility control) -- service point -- 100A conductors under the NEC -- 200A breaker, that's an NEC problem that needs to be fixed, either by downsizing the breaker, or upsizing the conductors from the service point to the breaker.

Note that with an underground electrical service that rises directly into a combination meter / main breaker piece of equipment, it is possible that the service point is at the utility side of that meter, and all the conductors between the service point and the main breaker are part of the factory assembled meter / main breaker equipment. In which case if that equipment is rated 200A, the size of the conductors landing on the utility side of the meter is not subject to the NEC.

In all cases, if you replaced 100A rated equipment with 200A rated equipment with a 200A main breaker, the utility needs to be notified of that, and may have their own procedures triggered by that upgrade.

Cheers, Wayne

Hi Wayne, I assume the service point is the drop down? The electric pole is literally in my back yard and the wire goes from that to the corner of my house where there is a drop down. I estimate it is about 50 - 60 feet total. Is the point of service where that wire from the pole meets with the wires on the drop down pole? I know the wires on the drop down pole were also changed by the electrician and the utility guy did something up there, too. I am drawing less than 10 amps at my meter per my Emporia vue monitor with my window AC going all day and cooking dinner with my overhead fan, and all my frig and freezers going. When I do laundry tomorrow, will see what my gas dryer and washer draw.

 

[729Zoom]

Per the NEC, there's a certain point on the electrical supply to your house called the service point. The utility is responsible for the wire on the utility side of the service point; if they use #6 Al for 200A there, it's on them, and if it burns up, they'll replace it. On an overhead service, often the service point is where the wires from the pole are spliced to the wires coming down the side of your house, near the top of the conduit riser called the weatherhead.

On the house side of the service point, your responsibility begins, and the NEC sizing rules apply. And one of those rules is that if a single breaker shuts off all the power to your house, the size of your conductors needs to match the size of that breaker. So if that breaker is 200A, that's fine, as long as the wires from the service point to that breaker are rated for 200A.

If you have #6 Al (under utility control) -- service point -- 100A conductors under the NEC -- 200A breaker, that's an NEC problem that needs to be fixed, either by downsizing the breaker, or upsizing the conductors from the service point to the breaker.

Note that with an underground electrical service that rises directly into a combination meter / main breaker piece of equipment, it is possible that the service point is at the utility side of that meter, and all the conductors between the service point and the main breaker are part of the factory assembled meter / main breaker equipment. In which case if that equipment is rated 200A, the size of the conductors landing on the utility side of the meter is not subject to the NEC.

In all cases, if you replaced 100A rated equipment with 200A rated equipment with a 200A main breaker, the utility needs to be notified of that, and may have their own procedures triggered by that upgrade.

Cheers, Wayne

PS - is there any scenario in which the undersized service wire would burn with a 200 amp panel and main breaker with all wires rated for 200 amps on my side If I never draw more than 40-50 amps? I can't imagine, based on today's readings, going over even 20 or 30 amps but I just want to make sure there are no other factors?

 

[brycenesbitt]

PS - is there any scenario in which the undersized service wire would burn with a 200 amp panel and main breaker with all wires rated for 200 amps on my side If I never draw more than 40-50 amps? I can't imagine, based on today's readings, going over even 20 or 30 amps but I just want to make sure there are no other factors?

Nobody here will or can recommend undersized wires are safe.
What if you rent the house on AirBnB and someone brings a bunch of space heaters?
This is a POCO question and issue.
You have TWO wire sizes: meter to service point, and service point to pole. You probably don't know what goes from service point to pole, and it's the POCO's job to make sure that's OK whey they pulled the meter.

 

[729Zoom]

Nobody here will or can recommend undersized wires are safe.
What if you rent the house on AirBnB and someone brings a bunch of space heaters?
This is a POCO question and issue.
You have TWO wire sizes: meter to service point, and service point to pole. You probably don't know what goes from service point to pole, and it's the POCO's job to make sure that's OK whey they pulled the meter.

Thanks for replying. My wire is also undersized for 100 amp panel, which was what was here when I bought the house 42 years ago. So, now I am thinking that the 100 amp panel might not have been the original panel. I am going to call my utility company tomorrow and find out what is going on in my neighborhood because we all have the same size wires and I don't know anyone who has less than 100 amps.

 

[Fred B]

Thanks for replying. My wire is also undersized for 100 amp panel, which was what was here when I bought the house 42 years ago. So, now I am thinking that the 100 amp panel might not have been the original panel. I am going to call my utility company tomorrow and find out what is going on in my neighborhood because we all have the same size wires and I don't know anyone who has less than 100 amps.

Still there are 2 separate codes that would govern a service installation. Customer concern usually only related to wiring "on and in" the house and is covered by the NEC. Wiring before house or service point is controlled by the utility and the NESC, and typically will be much smaller than required by the NEC.
Now if the contractor didn't change the wire feeding the main breaker from the meter and service point to one that is required for the main breaker size then you have a problem.


image from NFPA 70 2023

 

[electrofelon]

So it sounds like the conductors on your side of the service point were NOT upgraded to a 200A rating. This is a very clear and blatant code violation. Any real electrician should have known this. Did a real electrician do this work? The 100 amp and 200 amp breakers will be a different frame size so you can't just swap it out. What you are probably have to do is back feed a 100 amp Branch breaker and use it as your main breaker which is allowed as long as the manufacturer offers a hold down kit for it.

 

[Fred B]

So it sounds like the conductors on your side of the service point were NOT upgraded to a 200A rating. This is a very clear and blatant code violation. Any real electrician should have known this. Did a real electrician do this work? The 100 amp and 200 amp breakers will be a different frame size so you can't just swap it out. What you are probably have to do is back feed a 100 amp Branch breaker and use it as your main breaker which is allowed as long as the manufacturer offers a hold down kit for it.

Not sure Statement in post #12 would indicate the wire from service point to the meter and panel had been changed. Seems concern is the POCO wire size. OP not clearly articulating the exact points of changes and supposed undersized wire, just trying to guess from his various descriptions. Maybe a response related to image of "service point" might clear things up as OP comments indicate he not clear as to the demarcation point.

 

[electrofelon]

Not sure Statement in post #12 would indicate the wire from service point to the meter and panel had been changed. Seems concern is the POCO wire size. OP not clearly articulating the exact points of changes and supposed undersized wire, just trying to guess from his various descriptions. Maybe a response related to image of "service point" might clear things up as OP comments indicate he not clear as to the demarcation point.

There's been no mention of changing any wire, just changing the panel due to a bad bus bar. Wire from the service point to the panel clearly needs to be upgraded, POCO probably wouldn't change anything on their side.

 

[roger]

There's been no mention of changing any wire, just changing the panel due to a bad bus bar. Wire from the service point to the panel clearly needs to be upgraded, POCO probably wouldn't change anything on their side.

The OP stated the electrician did change the drop