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Solar Panels Design

You are lucky that your city has better taste. Do you have PW? The bozo nose is for shutting off ESS.
I think the button is unique to the PW 2+. To shutdown the solar system and activate the mid circuit interrupters on the roof you need to cut power to the inverter. Since the PW 2+ had an integrated inverter you can't use a normal blade disconnect (or the breaker) to cut power to the inverter since it can be powered by the PW 2+ internally.
 
Another PW would be nice and ideal but everything is out of my pocket since I can't get the SGIP rebate. The only thing I have to run is AC but I will try to minimize its usage. Stove, oven, dryer, furnace and water heater are all gas. I have also installed a wholehouse fan myself and my AC usage is way less now in the evenings unless it's very humid outside.
Forget running your AC - I would be worried about STARTING your AC, with just one Powerwall, in an off-grid/outage scenario.

A single Powerwall can supply 30A. That's it. The only way to increase your amperage is to add more Powerwalls.

Some AC compressors can require more than 100A (!) or more to start. It's a specification that can be found on your compressor called LRA, short for Locked Rotor Amps. So when your compressor tries to start, it will try to draw 100A (or more), and your lone Powerwall will give up and shutdown, and now your entire house is down hard.

So, check your AC compressor's LRA! If the LRA is low, like 20A or so, you're (probably barely) OK. Otherwise, there are several choices:

1. Add more Powerwalls (thereby increasing the max amperage your system can deliver).
2. Exclude your AC compressor from your backed up loads. This means you won't have any air conditioning during an outage. But, you won't overload and shutdown your system either.
3. Replace your AC compressor with a more modern compressor with a low LRA.
4. Get a "Soft Start" capacitor for your compressor. These will store hundreds of amps in advance, so that when your compressor starts, it will draw that huge surge of power from the capacitor and not your Powerwall.
5. Do nothing and drink heavily.

Me? I have two Powerwalls and a hog of a compressor (160 LRA) with a Soft Start. Starts with no problems whatsoever.

Fruitcake
 
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Forget running your AC - I would be worried about STARTING your AC, with just one Powerwall, in an off-grid/outage scenario.

A single Powerwall can supply 30A. That's it. The only way to increase your amperage is to add more Powerwalls.

Some AC compressors can require more than 100A (!) or more to start. It's a specification that can be found on your compressor called LRA, short for Locked Rotor Amps. So when your compressor tries to start, it will try to draw 100A (or more), and your lone Powerwall will give up and shutdown, and now your entire house is down hard.

So, check your AC compressor's LRA! If the LRA is low, like 20A or so, you're (probably barely) OK. Otherwise, there are several choices:

1. Add more Powerwalls (thereby increasing the max amperage your system can deliver).
2. Exclude your AC compressor from your backed up loads. This means you won't have any air conditioning during an outage. But, you won't overload and shutdown your system either.
3. Replace your AC compressor with a more modern compressor with a low LRA.
4. Get a "Soft Start" capacitor for your compressor. These will store hundreds of amps in advance, so that when your compressor starts, it will draw that huge surge of power from the capacitor and not your Powerwall.
5. Do nothing and drink heavily.

Me? I have two Powerwalls and a hog of a compressor (160 LRA) with a Soft Start. Starts with no problems whatsoever.

Fruitcake
My AC's LRA is 79. I have checked with Tesla, are they doing whole house backup for my 1 PW+. They confirmed it. I also heard that PW+ has soft start built in, I could be wrong.

I will have to run test when everything is set up to see if the AC starts. I know running AC off on one PW+ won't last long. I will turn off AC when there's a blackout and run whole house fan instead.
 

slcasner

Active Member
Supporting Member
Feb 20, 2011
1,424
965
Sunnyvale, CA
So you just have normal blade disconnect(s)?
None of them, either. On my old PV system installed in 2000 I had a blade disconnect, but that was removed along with the rest of that old PV system as the Solar Roof was installed.
Need pics of your new roof!
Yes, when I get a moment I plan to make a proper post with photos and some extra tidbits I expect will be of interest.
 

holeydonut

Active Member
Supporting Member
Jun 27, 2020
2,596
1,927
East Bay NorCal
None of them, either. On my old PV system installed in 2000 I had a blade disconnect, but that was removed along with the rest of that old PV system as the Solar Roof was installed.

Yes, when I get a moment I plan to make a proper post with photos and some extra tidbits I expect will be of interest.


You don't have any blade disconnects? How did you pass inspection??? 🤯⚡
 

oktane

Active Member
Oct 25, 2016
1,978
2,925
USA
I’d upgrade the panel. EVs aren’t going anywhere and charging requirements will grow. 100A is nothing I’ve already maxed out my 400A panel.

You might be able to upgrade to 200A without running new cable or the transformer
 

BGbreeder

Member
Jun 19, 2020
546
330
Bay Area
Or you can do what a local gas station does;
77809F1F-2214-46C8-9124-4D4B9C637374.jpeg
 
Unfortunately, my project is still pending installation permit installation. I went back to review the SCE Interconnection Agreement that Tesla had me signed a while back. It stated that:

1639153575669.png


Actually, I'm getting a 10.2 kW system with 1 PW+ . Is this concern that I have to get Tesla to correct it?
 

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