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Service panel upgrade

Eugene k.

Member
Apr 1, 2016
47
22
CA
Would like some feedback from anyone who looked into this, preferably in California but input from other states is welcome too.

My service panel is, as far as I know, 200 amp, and it is completely full. As in, literally, no room left to put in new breakers (and even the ones I have seem to add up to more than 200. I don't understand how people even live with 100 amp panels. Just the two A/C's, the oven and the induction cooktop add up to 150. Not that they are ever on at the same time, but still.)

So, my options are to charge at 120V/15A for the time being, to cut into the line for one of the A/C's with a double pole / double throw switch, or to upgrade the panel.

I am fairly familiar with anything that's my side of the main breaker (I did a DIY ground mount solar install a couple of years back, complete with drawing up permits), but I have no idea what's on the other side. The "other" half of the panel seems to belong to the utility company (SDG&E) since they have a "smart" meter and a seal there.

Now, the questions.

* For a service panel upgrade, do I get an independent electrician, or do I just call the utility company? It looks like they need to be deeply involved anyway. Or do I get an electrician and he coordinates with the utility? How long would _that_ take?

* What about the line from the distribution transformer to the service panel? What's the typical rating there, and is there any way to find out? Mine is buried all the way along, ~100 ft, and I really, really don't want to excavate it for an upgrade.

* How much would an electrician typically charge for an upgrade to 400A?
 

mongo

Well-Known Member
May 3, 2017
13,974
45,334
Michigan
Would like some feedback from anyone who looked into this, preferably in California but input from other states is welcome too.

My service panel is, as far as I know, 200 amp, and it is completely full. As in, literally, no room left to put in new breakers (and even the ones I have seem to add up to more than 200. I don't understand how people even live with 100 amp panels. Just the two A/C's, the oven and the induction cooktop add up to 150. Not that they are ever on at the same time, but still.)

So, my options are to charge at 120V/15A for the time being, to cut into the line for one of the A/C's with a double pole / double throw switch, or to upgrade the panel.

I am fairly familiar with anything that's my side of the main breaker (I did a DIY ground mount solar install a couple of years back, complete with drawing up permits), but I have no idea what's on the other side. The "other" half of the panel seems to belong to the utility company (SDG&E) since they have a "smart" meter and a seal there.

Now, the questions.

* For a service panel upgrade, do I get an independent electrician, or do I just call the utility company? It looks like they need to be deeply involved anyway. Or do I get an electrician and he coordinates with the utility? How long would _that_ take?

* What about the line from the distribution transformer to the service panel? What's the typical rating there, and is there any way to find out? Mine is buried all the way along, ~100 ft, and I really, really don't want to excavate it for an upgrade.

* How much would an electrician typically charge for an upgrade to 400A?

IF the load calculation supports it, you could add a sub panel to create room for more breakers.

Power company lines might need upgraded, transformer might need upgraded. Power Company isn't going to work on anything past the meter (possibly not the meter base either, just the main feed connection).
 
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MikeBur

ManualPilot
Dec 8, 2014
1,379
745
Seattle, WA
In process of similar situation, albeit in WA state

Get an electrician, IMO. Every time you touch feed lines, hire a pro.

The utility should know both the service line capacity AND the transformer rating. They err on the conservative.
They likely will not tell a muggle this information, and likely you’ll need to have a licensed journeyman or master electrician call

If the transformer needs upgrading, then you have a battle beyond my knowledge ;)
If the feed line needs upgrading then you will likely need then to run their cable through your trenched conduit. If you run the cable then they will not warranty after the transformer.
If the feed line doesn’t need upgrading then you will still likely need a service upgrade from the ground feed to the meter, and from the meter to the panel

You may need to upgrade the panel you have, though hopefully not, as well as adding new panel and distribute loads more evenly. You should think about moving all breakers you wish to backup to one panel for ease.

My cost for service upgrade (ditch, pad, new line from feed, meter stuff, etc), no new feed line/trenching (phew), new panel, etc was ~2k
 

Eugene k.

Member
Apr 1, 2016
47
22
CA
IF the load calculation supports it, you could add a sub panel to create room for more breakers.
As I said, I think the panel is overloaded as-is.

Power company lines might need upgraded, transformer might need upgraded. Power Company isn't going to work on anything past the meter (possibly not the meter base either, just the main feed connection).

They were the ones who installed the meter, I'd assume that they would not want me or even some random licensed electrician to touch it without their permission.
 

mongo

Well-Known Member
May 3, 2017
13,974
45,334
Michigan
They were the ones who installed the meter, I'd assume that they would not want me or even some random licensed electrician to touch it without their permission.

By you I mean an electrician. Electricians typically do not mess with the PoCo side of the meter. But they do work after the main breaker without consulting them. (varies a little if it is a combo meter/breaker panel or separate units).
 

Eugene k.

Member
Apr 1, 2016
47
22
CA
By you I mean an electrician. Electricians typically do not mess with the PoCo side of the meter. But they do work after the main breaker without consulting them. (varies a little if it is a combo meter/breaker panel or separate units).

It's a combo panel.
20180316_154038.jpg

If PoCo won't work downstream of the meter, and the contractor won't work upstream of the meter, it sounds like this consists of two separate jobs.

* Get the utility company to upgrade some subset of the transformer, feed line, and the meter. (Just checked out the meter and it's rated 200 amp, so that one definitely needs to be upgraded.)
* Get an electrician to replace the breaker panel itself.

Except there's a catch-22: the electrician would have to pull out the meter and disconnect the power on the transformer side of the feed in order to replace the panel itself.

Looks like I'll need to pay $700+ just for the new panel, before any of the labor.

Tried to call the utility company just now, got transferred to project management, it's 3:30 PM local and no one is picking up the phone. They all must be celebrating TGIF already. Will try again on Monday.
 

mongo

Well-Known Member
May 3, 2017
13,974
45,334
Michigan
It's a combo panel.
View attachment 287034

If PoCo won't work downstream of the meter, and the contractor won't work upstream of the meter, it sounds like this consists of two separate jobs.

* Get the utility company to upgrade some subset of the transformer, feed line, and the meter. (Just checked out the meter and it's rated 200 amp, so that one definitely needs to be upgraded.)
* Get an electrician to replace the breaker panel itself.

Except there's a catch-22: the electrician would have to pull out the meter and disconnect the power on the transformer side of the feed in order to replace the panel itself.

Looks like I'll need to pay $700+ just for the new panel, before any of the labor.

Tried to call the utility company just now, got transferred to project management, it's 3:30 PM local and no one is picking up the phone. They all must be celebrating TGIF already. Will try again on Monday.

So the main feed runs inside the wall to the meter? That may complicate things along with panel being recessed in the stucco. Is the main breaker located above the meter?

If new panel/ meter base goes in the same spot as old, PoCo cuts power at transformer and pull meter, electrician removes old panel and meter base and installs new one, PoCo comes back and connects feed to meter and transformer (possibly with a new run). If the electrician has all the circuits removed ahead of time, this might all happen in one PoCo trip, but depends on inspectors also.
https://www.sdge.com/sites/default/files/UndergroundElectService.pdf

If the new panel goes in a different location, electrician can mount panel /meter base. Then poco runs the new feed to the new meter base and removes the old feed. Might be possible in this scenario to add a 200A breaker to the new panel to feed the old one.

PoCo likely has a list of approved meter bases/ panel combos.
 

Eugene k.

Member
Apr 1, 2016
47
22
CA
PoCo cuts power at transformer and pull meter, electrician removes old panel and meter base and installs new one, PoCo comes back and connects feed to meter and transformer (possibly with a new run). If the electrician has all the circuits removed ahead of time, this might all happen in one PoCo trip, but depends on inspectors also.
:eek:
In this scenario, for how many weeks should I expect the house to be without power?
 

mongo

Well-Known Member
May 3, 2017
13,974
45,334
Michigan
:eek:
In this scenario, for how many weeks should I expect the house to be without power?

Take anything I say with a big grain of salt since I'm not in your area. Get some quotes from local electricians, they will give you reliable data, instead of theoreticals from some guy in Michigan:).
There are options to keep your house going during switchover like a temporary service (meter and panel on ground mount post) or a generator. This type of thing is not rare, so I'd expect they have the logistics fairly worked out.
 

davewill

Active Member
Feb 5, 2014
1,831
2,086
San Diego, CA, US
Adding up the breakers is NOT how you determine whether your panel is overloaded. Have an electrician do a proper load calculation for you. It is very common for the breakers to add up to more than the panel capacity. If it is not overloaded, then a subpanel is the way to go. If you truly don't have capacity, THEN you can ask for a quote to upgrade.
 

Eugene k.

Member
Apr 1, 2016
47
22
CA
That's one drawback of having hard-science education! It never even occurred to me that the maximum load on the panel can be anything other than the maximum current that can be drawn by all breakers in the panel.
However, now that you've pointed this out, I found a PDF called "NEC Standard Electrical Load Calculation for Single Family Dwellings" and tried to use it to get a ballpark estimate. I easily get over 190, and it does not even have any entries for my computers (which have been known to trip the 15A breaker before I started spreading them over multiple circuits) or my entertainment equipment. I need to get into the attic and check nameplate loads of the HVACs, but it's doubtful that I have 50A to spare for a charger.
 

mongo

Well-Known Member
May 3, 2017
13,974
45,334
Michigan
That's one drawback of having hard-science education! It never even occurred to me that the maximum load on the panel can be anything other than the maximum current that can be drawn by all breakers in the panel.
However, now that you've pointed this out, I found a PDF called "NEC Standard Electrical Load Calculation for Single Family Dwellings" and tried to use it to get a ballpark estimate. I easily get over 190, and it does not even have any entries for my computers (which have been known to trip the 15A breaker before I started spreading them over multiple circuits) or my entertainment equipment. I need to get into the attic and check nameplate loads of the HVACs, but it's doubtful that I have 50A to spare for a charger.

Similar to what you mentioned earlier, you may be able to use a sub panel set up with a mechanical interlock such that your EV plug and another large load do not operate simultaneously. Not the most convenient depending on how often you use the other load.
 

RandyS

Fan of Elon
Jul 8, 2012
766
1,010
San Diego
Would like some feedback from anyone who looked into this, preferably in California but input from other states is welcome too.

My service panel is, as far as I know, 200 amp, and it is completely full. As in, literally, no room left to put in new breakers (and even the ones I have seem to add up to more than 200. I don't understand how people even live with 100 amp panels. Just the two A/C's, the oven and the induction cooktop add up to 150. Not that they are ever on at the same time, but still.)

So, my options are to charge at 120V/15A for the time being, to cut into the line for one of the A/C's with a double pole / double throw switch, or to upgrade the panel.

I am fairly familiar with anything that's my side of the main breaker (I did a DIY ground mount solar install a couple of years back, complete with drawing up permits), but I have no idea what's on the other side. The "other" half of the panel seems to belong to the utility company (SDG&E) since they have a "smart" meter and a seal there.

Now, the questions.

* For a service panel upgrade, do I get an independent electrician, or do I just call the utility company? It looks like they need to be deeply involved anyway. Or do I get an electrician and he coordinates with the utility? How long would _that_ take?

* What about the line from the distribution transformer to the service panel? What's the typical rating there, and is there any way to find out? Mine is buried all the way along, ~100 ft, and I really, really don't want to excavate it for an upgrade.

* How much would an electrician typically charge for an upgrade to 400A?

Eugene, I work at the utility in the Clean Transportation group and have worked on several projects like this.

* The size that is stamped on your main breaker is usually the size of your service panel. It could very well be 200 amps, but it wouldn't hurt to check in case it is smaller.

* An electrician can use NEC methods to calculate available capacity in your panel, but it looks like you've done that somewhat and have come to the conclusion that your panel is near capacity.

* If you have a 200 amp panel, the next major size upgrade is to 400 amps. I've seen people upgrade from 125 to 225, but an extra 25 amps in your case is not much improvement for all the work necessary.

* If you wanted to pursue a 400 amp upgrade, you would need to hire a contractor/electrician and call the utility's main phone number to establish a relationship with your area's Service Planner and eventually arrange a site meet with the Planner and your contractor (you would be asking for an upgraded electric service). He/she will do research on the mapping system and tell you the details about the status of the connection that goes from your panel to the distribution transformer. This will depend on how old your home is. Sometimes there is conduit installed, and larger wire can be pulled to support larger panels. The size of the conduit will determine if you can go all the way up to 400 amps. In most cases, my experience is that you will have to install new conduit (but you may get lucky, depending on the age of the installation). That probably means trenching across driveways, sidewalks, etc. and restoring after the conduit is put in.

* The Planner will write up a "Service Order" that will contain all the details about the job for the contractor/electrician. You will use this Service Order to get a permit from your City.

* Once the permit is issued, then work can begin. Let's say you have good conduit and just need new wire pulled to service the new larger panel. This is what happened to me. The utility sent a crew out at 8am and pulled out the wire from my panel to the transformer, and left a pull rope in the conduit. Then the electricians tore my old panel out and installed a new larger panel (at the same time my solar was installed). They got the new panel installed and wired up. The utility crew came back in the afternoon and pulled in new larger wire at no cost to me (there is an allowance for this work that wasn't exceeded).

* The City inspector came out and blessed the installation and the main breaker was energized. So my service panel swapout was done in one day (along with my solar installation). I had a 6-7 hour outage and everything was turned back on. The solar was inspected the next day and permission to operate was given in one day by the utility. My panel upgrade was $2,500 including the permit and I received a 30% tax credit because it was done as part of the solar install.

If you have to do the trenching for larger conduit, it can get expensive. But you won't know the extent of any work required until you contact the utility and get the Planner involved...

I hope that helps....
 

RDaneel

Member
Apr 3, 2016
162
176
New Jersey
You might also be able to consolidate some of your lower-draw circuits onto tandem breakers, which do a 2:1, freeing up space. I have 200A service with a totally full panel and a totally full subpanel (the builder put practically everything on a separate breaker, for unknown reasons). I'm having minor circuits moved to the subpanel and half-height breakers installed to make room for a new 50A breaker for my garage outlet.
 

Eugene k.

Member
Apr 1, 2016
47
22
CA
You might also be able to consolidate some of your lower-draw circuits onto tandem breakers, which do a 2:1, freeing up space. I have 200A service with a totally full panel and a totally full subpanel (the builder put practically everything on a separate breaker, for unknown reasons). I'm having minor circuits moved to the subpanel and half-height breakers installed to make room for a new 50A breaker for my garage outlet.

This was a good suggestion, but it turns out that all my breakers are tandem already :confused:

Called the utility again on Monday, left them a voicemail, they promised to call back within 24 hours. Which they didn't, of course.

At this point, I think I'll just go through existing breakers and consolidate them to make room for one more double-pole breaker (there's no way I need 20 15A breakers in the house, I'm not even sure what most of them do), and put in a NEMA14-30 plug as a compromise.
 

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