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Solar Panels Design

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That's an old panel. I would think if there were an 80A branch breaker limit for a panel like that, the label would explicitly say so. Perhaps @Vines would know. Maybe at the time that that label was printed, the breaker types listed only went up to 80A, so there's an implicit 80A limit.

Otherwise, I don't see why Tesla wouldn't use a 100A branch breaker and a 100A feeder.

Cheers, Wayne
Thanks Wayne, yes indeed it's an old panel.
 
@wayne I contacted Crouse hinds for the max Branch Rating. The business has been sold to Siemens, they told me it's 100A. I told Tesla the same and asked them not to downsize my breaker, hopefully they will change the design.

I have a Crouse-Hinds panel with 125A bus and 100A main but it is a different model. My design from Tesla (yet to be installed) includes a 100A feeder breaker.
Is your panel as old as mine? I don't know why they downsized it,thanks to @GenSao for calling it out. When I checked with Tesla, they said it's the max for my panel.
 
Mine is from 1980.
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My briefly looking into this shows that indeed a 100A is available for this panel. It's made by siemens, and those breakers are replacing the old Crouse-Hinds breakers.

Reach out to a breaker supply house like Circuit Breakers, Motor Controls, Switches/Disconnects, and Other Electrical Hardware - BayBreakers.com with the picture to confirm what will fit.
Thanks. Yes, I have reached out to Siemens last week. They confirmed the max branching rate is 100A and can use QP frame breakers.
 
This is the latest update: they are saying whole house will be back up to PW+ and do not need to downsize the main breaker. So I asked them to update the three line diagram, they said no need.
I would think they would need to update it to pass inspection. The installers also need the plans to know what they are installing. I would be worried that without it being documented you might not get what you want on install day.
 
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I would think they would need to update it to pass inspection. The installers also need the plans to know what they are installing. I would be worried that without it being documented you might not get what you want on install day.
I would agree with you so no confusion for the installation. I kept asking them to update the 3 line diagram, they said no need.

The advisor is telling me that 100A main breaker in the diagram is correct, not being downsized. The 80A breaker shown in the diagram is for their equipment.

Does this sound correct?

@Vines
@wayne
 
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I would agree with you so no confusion for the installation. I kept asking them to update the 3 line diagram, they said no need.

The advisor is telling me that 100A main breaker in the diagram is correct, not being downsized. The 80A breaker shown in the diagram is for their equipment.

Does this sound correct?

@Vines
@wayne
They are completely missing your point and essentially saying they are going to install it as your plans currently show it hence there is no need to update them.
 
The advisor is telling me that 100A main breaker in the diagram is correct, not being downsized. The 80A breaker shown in the diagram is for their equipment.

Does this sound correct?
No. If the only thing behind (on the opposite side of the grid) the 80A breaker were the new Tesla equipment, that would be fine. But all of your loads are also going behind it. So it is now the new bottleneck to the grid and reduces your grid capacity to the loads from 100A to 80A. That is unacceptable.

Tell them that _both_ breakers in the service panel need to be 100A, and that you would like the conductors in sections 11 and 12 upsized from #4 Cu to #3 Cu. [The latter is not actually currently required when the service size is 100A, but if you ever upsize the service and had #4 conductors there, you'd need need to downsize the current 80A breaker (to become 100A) to 90A.]

Cheers, Wayne
 
No. If the only thing behind (on the opposite side of the grid) the 80A breaker were the new Tesla equipment, that would be fine. But all of your loads are also going behind it. So it is now the new bottleneck to the grid and reduces your grid capacity to the loads from 100A to 80A. That is unacceptable.

Tell them that _both_ breakers in the service panel need to be 100A, and that you would like the conductors in sections 11 and 12 upsized from #4 Cu to #3 Cu. [The latter is not actually currently required when the service size is 100A, but if you ever upsize the service and had #4 conductors there, you'd need need to downsize the current 80A breaker (to become 100A) to 90A.]

Cheers, Wayne
Thank you Wayne for the details. I copied and pasted your explanations in the email to the advisor....hopefully this will go somewhere this time. This has been going back and forth for a while.
 
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After going back and forth with Tesla and 2 weeks of wait, they have finally agreed to update the feeder breaker to 100A. Thanks everyone, especially @GenSao ,@wwhitney ,@yblaser for your great help, really appreciate it.

I proposed 4 alternative locations by my house for them to install the PW+ outside instead of inside of my garage but they decided to put it another location outside of the garage, oh well...I don't have time to keep going back and forth.

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After going back and forth with Tesla and 2 weeks of wait, they have finally agreed to update the feeder breaker to 100A. Thanks everyone, especially @GenSao ,@wwhitney ,@yblaser for your great help, really appreciate it.

I proposed 4 alternative locations by my house for them to install the PW+ outside instead of inside of my garage but they decided to put it another location outside of the garage, oh well...I don't have time to keep going back and forth.

View attachment 731608View attachment 731609 View attachment 731610
Congratulations. Glad your persistence finally got Tesla to do the right thing.
 
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Unfortunately, until now, I don't even know when my system will get installed by. I really hope to get PTO before NEM 3 is in effect.
Certainty understand the concern. You've probably read enough here but understand what's next.

Tesla needs to file the updated permits. You can check with your city on the progress. Once the permits were filed it took Tesla 3-4 weeks to install. For me with some updates during the install it was another 4 weeks for the first and hopefully last inspection to be scheduled (for next week).

Who knows how long PTO will take given some of the horror stories here. Again you can attempt to manage this if your persistent.

They're going to make a decision on NEM 3 in January but I expect it will take many months to implement. Not worth gambling with if you can help it of course.
 
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Certainty understand the concern. You've probably read enough here but understand what's next.

Tesla needs to file the updated permits. You can check with your city on the progress. Once the permits were filed it took Tesla 3-4 weeks to install. For me with some updates during the install it was another 4 weeks for the first and hopefully last inspection to be scheduled (for next week).

Who knows how long PTO will take given some of the horror stories here. Again you can attempt to manage this if your persistent.

They're going to make a decision on NEM 3 in January but I expect it will take many months to implement. Not worth gambling with if you can help it of course.
In my case, they haven't even filed any permit yet as I asked them to update design.

Yea, it's not fun to keep calling them every day or so and mine is far from over....yea, after they confirm they file the permit, I will start to "harass" the la county permit office. I heard that lead time will take at least 2-4 weeks.

Good luck with yours, I think you are at least half way there 😉
 
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