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Panel upgrade

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They are probably looking at downgrading your main to a 150A and then limited to a 90A for the powerwalls as that would be 240A or 120% of a 200A panel.

If that is the reason, they probably could derate your main to a 125A and then they could use a 100A breaker for your powerwalls. However, you might need more than 125A for the load you use in your house.

Likely this is the reason, the load calculations show a load required of more than 125A.

However assuming the AHJ allows it, there is no reason why you cannot use the Gateway 2 Export limits to eliminate the Powerwalls from the 120% rule calculation, on upstream busbars.
 
close up of branch breakers
 

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In your case the issue is that the maximum breaker your service panel will allow is 90A.

There are ways to make this work but you will be limited to 90A of grid power on the backup circuit. You wont make whole home backup work with that panel.

so would upgrading the panel to a 200 amp with 225 bus work? or is there something called 225 amp panel with 225 amp bus? sorry for silly questions. I am learning all this mumbo jumbo now..
 
so would upgrading the panel to a 200 amp with 225 bus work? or is there something called 225 amp panel with 225 amp bus? sorry for silly questions. I am learning all this mumbo jumbo now..

Yes, 200 with 225A is a panel that is installed and it'll do stuff, even work?

Will this panel work for a specific use case requires significantly more info. Will it work for what?
 
Likely this is the reason, the load calculations show a load required of more than 125A.

With the energy improvements in lighting, appliances and equipment, there are probably a number of people who are unnecessarily upgrading their panels. Shame that the alternative of measuring the load isn't easier for a home owner to do. And Tesla probably wouldn't accept it anyways and would go with the calculated value.
 
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Yes, 200 with 225A is a panel that is installed and it'll do stuff, even work?

Will this panel work for a specific use case requires significantly more info. Will it work for what?

sorry I was not clear..

Tesla permit with LA County says this in subject line----> "Installation of roof-mounted PV, 8.16 kw, 24 modules, 1 (N) 200A Load Center, 1 (N) 225A Distribution panel, 1 (N) 125A Load Center (2) Tesla Powerwall (ESS)"

I am assuming the main panel is the '200A load center' ? I already have the 200A panel but with a lower bus rating than the needed 225A. Is my understanding correct here?
 
With the energy improvements in lighting, appliances and equipment, there are probably a number of people who are unnecessarily upgrading their panels. Shame that the alternative of measuring the load isn't easier for a home owner to do. And Tesla probably wouldn't accept it anyways and would go with the calculated value.

So true. All my lights are LED including the ones that comes in fan domes.
 
sorry I was not clear..

Tesla permit with LA County says this in subject line----> "Installation of roof-mounted PV, 8.16 kw, 24 modules, 1 (N) 200A Load Center, 1 (N) 225A Distribution panel, 1 (N) 125A Load Center (2) Tesla Powerwall (ESS)"

I am assuming the main panel is the '200A load center' ? I already have the 200A panel but with a lower bus rating than the needed 225A. Is my understanding correct here?

Hard to say from permit comments. What do your plans look like?

As far as load calculations its true that many houses use less power per device, however I'd be surprised if overall the house trend isnt to heavier power useage overall. As electric cars get more popular homes will need more not less capacity. A dozen LED lights vs incandecent barely registers on your main panel load. Its things like an EV charging, air and water heating and cooling, and pumping water that make the biggest demand on a main panel.
 
Hard to say from permit comments. What do your plans look like?

As far as load calculations its true that many houses use less power per device, however I'd be surprised if overall the house trend isnt to heavier power useage overall. As electric cars get more popular homes will need more not less capacity. A dozen LED lights vs incandecent barely registers on your main panel load. Its things like an EV charging, air and water heating and cooling, and pumping water that make the biggest demand on a main panel.

I don't have access to plan. I have requested Tesla and LA County to give me access.. will wait for a few more days..
 
The panel shown will take a 200A breaker right on the bus. Its ready to go for a 100% rule. I cannot speak to the possible issues with the Gas meter, as you aren't showing it. If the MSP was signed off its usually grandfathered in unless PGE has a wild hair to make life difficult.
I learn something new from almost every post you make.
This is from the Square D label image above:
TWO POLE TYPE HOM OR HOMA (110-125A) MAY PLUG ON TWO ADJACENT SPACES. TWO POLE TYPE HOMA (150-200A) MAY PLUG ON FOUR ADJACENT SPACES
My Square D panel has the same language except the 4 adjacent spaces must be on the right hand side of the panel bus. I previously thought the two pole 2 space 125A breaker that is currently supplying my Gateway was the largest allowed.
 
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The panel shown will take a 200A breaker right on the bus. Its ready to go for a 100% rule. I cannot speak to the possible issues with the Gas meter, as you aren't showing it. If the MSP was signed off its usually grandfathered in unless PGE has a wild hair to make life difficult.

Here is a pic of the panel and the gas meter. Note Tesla seems to have moved off this being an issue. But who knows if it will come back.

The next thing they said is I need new service and trenching for $15K. I told them I already have 200AMP service and once again reminded them that panel had been updated 3 years ago. They then moved off that as an issue.

Now the only issue remaining is a $5,000 Main Panel Upgrade.

I also agree - based on the label inside the panel (pic attached) it says the BUS is rated to 225 and there is some note about a kit for a 200 AMP branch circuit? And another note about 100 AMP branch circuits.

I have read elsewhere that there might be an issue with the meter being integrated with the panel? This was the email that Tesla Coordinator sent:
"I’ve been helping other TESLA Customers and could not follow-up immediately. I contacted the Electrician Coordinator to let them know you had a Main Panel Upgrade to 200A two years ago.

They updated your plan to reflect the 200A main panel and let me know that there’s no longer a need for the Trenching work, which would have been the majority of the cost however, your existing panel is not compatible with the TESLA Gateway needed to install PowerWall. The Gateway is a TESLA proprietary system. This is the reason that the MPU remains."

I had a Tesla site inspection and I uploaded photos of all panels and labels. I am so frustrated that the Tesla Electrician seems to be flying blind despite all the documentation/ visit.

IMG_4432.jpg IMG_4433.jpg IMG_4434.jpg IMG_4435.jpg
 
A solar ready panel is a panel that has bus bars that are rated to handle more power than the main breaker because of the 120% rule. Essentially that says that the panel can be fed with a total of 120% of the bus bar rating. So on a normal 200A panel the bus bars would be rated for 200A. Applying the 120% rule means that you can feed that panel with a max of 240A. If you have a 200A main breaker that only leaves 40A left for your solar system. A large solar system will require more than a 40A breaker.

The solar ready panel will have bus bars rated at, say, 250A, so applying the 120% rule to that gives you 300A. With a 200A main breaker that allows you to have up to 100A for your solar system.

However, all that is irrelevant for a powerwall install because the solar breakers won’t be put in the meter main panel. In fact, if you have a whole house backup you won’t have any circuits in your meter main except for the feed to Tesla Energy Gateway.

The problem that you run into with a powerwall install that may necessitate the replacement of your meter main panel is that some panels don’t allow for 200A breakers on the bus. Since all of your utility power will be fed through the gateway it needs a 200A breaker in your meter main panel. If your panel doesn’t support 200A breakers then it will need to be replaced.

I don’t know anything about that panel, so it’s possible that there’s another issue with it. But just because it’s solar ready doesn’t necessarily mean that it’s ‘powerwall ready’.
 
Thanks this is very helpful information. The labels inside the panel suggest the BUS Bar is rated at 225 (so my panel should handle 270 amps. So I guess they could downsize the main breaker to 150A and that would give the powerwall + solar 120 AMPS. So I probably need to drop down to 2 PWs (60 and that would leave 60 for Solar)?
IMG_4433.jpg
 
Thanks this is very helpful information. The labels inside the panel suggest the BUS Bar is rated at 225 (so my panel should handle 270 amps. So I guess they could downsize the main breaker to 150A and that would give the powerwall + solar 120 AMPS. So I probably need to drop down to 2 PWs (60 and that would leave 60 for Solar)?
View attachment 592642

There is no need to upgrade that panel. They are probably just stuck in a loop.

The company I work for would simply put a 200A 4 pole on the bus of the MSP, relocate all those loads to a new subpanel within 5' and be done. This is a slam dunk, no need to make it hard. Its even easier if the garage is on the other side, or even just a room where you didn't mind a new subpanel on the interior wall.

Maybe one of these days Tesla will hire me lol, I am part of their 3rd party tech support.
 
I learn something new from almost every post you make.
This is from the Square D label image above:

My Square D panel has the same language except the 4 adjacent spaces must be on the right hand side of the panel bus. I previously thought the two pole 2 space 125A breaker that is currently supplying my Gateway was the largest allowed.

I appreciate the compliment. I like sharing my knowledge and so many people have questions.

I also learn a lot here, especially from @wwhitney.
 
There is no need to upgrade that panel. They are probably just stuck in a loop.

The company I work for would simply put a 200A 4 pole on the bus of the MSP, relocate all those loads to a new subpanel within 5' and be done. This is a slam dunk, no need to make it hard. Its even easier if the garage is on the other side, or even just a room where you didn't mind a new subpanel on the interior wall.

Maybe one of these days Tesla will hire me lol, I am part of their 3rd party tech support.
That is music to my ears. I hope I can get in the phone and get this sorted with the design team at Tesla - if the project coordinator ever let’s me talk to them. I am tempted to call the Tesla employees phone number that is listed on the permit with the city. This thread has been so helpful in understanding how the Tesla power wall and solar work with the existing MSP. Why doesn’t Tesla provide these diagrams or schematics in their communication with homeowners? And yes, Tesla should hire you - their support is in need of an over the air knowledge update. I will let you know what happens next! Thanks
 
That is music to my ears. I hope I can get in the phone and get this sorted with the design team at Tesla - if the project coordinator ever let’s me talk to them. I am tempted to call the Tesla employees phone number that is listed on the permit with the city. This thread has been so helpful in understanding how the Tesla power wall and solar work with the existing MSP. Why doesn’t Tesla provide these diagrams or schematics in their communication with homeowners? And yes, Tesla should hire you - their support is in need of an over the air knowledge update. I will let you know what happens next! Thanks

The reason they wont give you access to those people is because this is how they keep the prices super cheap, remove customer access to the real knowledge. I already have a job at a smaller installer so it was more of a joke.

If they gave you diagrams, you'd ask more questions. Questions cost time and people, which Tesla wants to remove. Ideally they want you to click on the button, buy the system and then they figure it out and you get whatever delays or extras that ensue.

Alternatively you hire a smaller installer whos reputation requires them to be responsive to every call and email. This service costs money, and most people come here comparing their local installer pricing compared to Tesla. The differences are in the service, if it is this hard to get an answer on the front side. What answers will you get when they have your install complete? Will you still be a priority if your inverter or Powerwall goes down?
 
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As for providing diagrams at the planning stage, not a set of city approved installed plans, I’d be willing to bet that the vast majority of homeowners buying a system don’t care to see the line-drawings. They just want it set up, get their PTO and know the system is being maintained. Seriously doubt most people have an electrical background or care to learn the specifics of what’s installed.

Also doubt Tesla has enough trained design planners available to answer tons of phone questions and still do their design work. Wildfires areas and others wanting solar/solar+PWs across the country hoping for getting installs while the Federal incentives are still available is doing enough to keep these guys busy. In my area I heard there were 5 install teams working 6 days a week and staying fully booked. We had a 3-team doing our PW/equipment install and I think 6 on our solar team. One of our advisors said he had over 500 customers he was working with so apologized for any delay responding to calls or emails we might have sent. So really doubt anyone will get to directly speak with a designer.

I will say we have had a good response from Tesla getting back to us with questions. Sometimes got right through, otherwise within a day or two, and on a few occasions early on in the planning stage, within the week. I’d say most of our phone calls to get through and waiting on hold were 15 minutes or less, a few much longer. If you’re expecting immediate responses however or a different level of communication, like with design team directly, then a smaller firm with fewer customers might be the better route for you. That’s where they can shine if they are a good company. With Tesla you have a large growing base of customers orders and lower prices due to scale, but only so many employees to handle the influx of orders.
 
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