How to prevent PowerShare charging other EVs during outage?

[MilliVanilli]

We have two other EVs, each on their own chargers on dedicated circuits.

If the power goes out, I don't want my Cybertruck to power/charge the other two vehicles (if they were charging when the power went out, they'll resume charging once their power is restored). How can this be done?

I assume that I'll need to move the other EVs' charger circuits to a separate subpanel which will always be wired to the grid, and then the CT will be connected to the main panel (so it can disconnect from the other EVs' subpanel). But will this effectively force my main panel to lose max amperage capacity? (i.e., right now it's a single panel so all circuits share the entire capacity, but if I move two circuits to a subpanel, will that subpanel's total max amperage be subtracted from the main one?). I'm also worried that this will cost a ton of money to do.

Any insight is welcome!

Sponsored

 

[Gaximus]

This is a good question, I would think the Tesla App would handle this scenario. But if not I’m sure it can be done with HomeAssistant integrations.

 

[17hertz]

To my understanding you pick which circuits the ct will charge when it goes down. I could be wrong double check

 

[MilliVanilli]

Oh, I assumed PowerShare would backup an entire electrical panel for ease of installation; that's why I thought I would need to separate my circuits into two panels--one for loads that are okay to be out (like the other EV chargers), and another for loads that will be backed up. Wouldn't backing up specific circuits require replacing the electrical panel and rewiring everything? Sorry if I'm making a mess of this...I'm still trying to understand how this all works.

 

[carsly]

Oh, I assumed PowerShare would backup an entire electrical panel for ease of installation; that's why I thought I would need to separate my circuits into two panels--one for loads that are okay to be out (like the other EV chargers), and another for loads that will be backed up. Wouldn't backing up specific circuits require replacing the electrical panel and rewiring everything? Sorry if I'm making a mess of this...I'm still trying to understand how this all works.

I think you move a number of loads you want backed up to the Powershare circuits. But I cancelled my installation once I received an outrageous quote.

 

[Woodrick]

Oh, I assumed PowerShare would backup an entire electrical panel for ease of installation; that's why I thought I would need to separate my circuits into two panels--one for loads that are okay to be out (like the other EV chargers), and another for loads that will be backed up. Wouldn't backing up specific circuits require replacing the electrical panel and rewiring everything? Sorry if I'm making a mess of this...I'm still trying to understand how this all works.

Backing up the entire panel completely depends on the loads on the panel. There are a LOT of things that can require the panel to be split, large air conditioners, pool pumps, car charging. Anything that causes the load to be bigger than the truck can provide.

 

[jpend]

Oh, I assumed PowerShare would backup an entire electrical panel for ease of installation; that's why I thought I would need to separate my circuits into two panels--one for loads that are okay to be out (like the other EV chargers), and another for loads that will be backed up. Wouldn't backing up specific circuits require replacing the electrical panel and rewiring everything? Sorry if I'm making a mess of this...I'm still trying to understand how this all works.

There are several ways to look at this. You could move the charging circuits into a sub panel that’s not backed up, but this then requires a split prior to the gateway which could be expensive.

However I think there may be a better way. The PowerShare gateway is essentially a sub panel itself. My installer mentioned that several more chargers could be added with the breakers in the gateway.

The question is if these are backed up or can be configured to backup or not. I’m assuming, based on the conversation with the installer, Tesla has contemplated this. Even better, with Universal Chargers, could these be additional power sources (CT or another Tesla eventually) to increase the capacity?

I may have this exact scenario as we consider adding another charger if we get another Tesla.

 

[N800AN]

When the grid fails you run out and open the dedicated circuits you don't want on.

 

[darrenf]

I haven't figured out how it's doing this, but when my power goes out and the CT starts back-feeding through the gateway, my second Tesla, on a separate EVSE, that is not load-sharing with the CT's, immediately stops charging with a message about lost communication.

Again, I don't know how, but in the three tests that I ran, it refused to charge any time the CT was powering the house. And it's a good thing because the CT's EVPE and the second car's EVSE connect to the same panel, connected through another panel, that connects to the gateway so it would be a real PITA to separate them.

 

[MilliVanilli]

There are several ways to look at this. You could move the charging circuits into a sub panel that’s not backed up, but this then requires a split prior to the gateway which could be expensive.

However I think there may be a better way. The PowerShare gateway is essentially a sub panel itself. My installer mentioned that several more chargers could be added with the breakers in the gateway.

The question is if these are backed up or can be configured to backup or not. I’m assuming, based on the conversation with the installer, Tesla has contemplated this. Even better, with Universal Chargers, could these be additional power sources (CT or another Tesla eventually) to increase the capacity?

I may have this exact scenario as we consider adding another charger if we get another Tesla.

I found this thread from a few months back: https://www.cybertruckownersclub.co...teway-install-experience-and-explainer.17250/. It looks like the PowerShare gateway doesn't have any individual breakers, so it will only switch an entire panel that is external to it.

In the first video in that thread, the installers simply backed up the guy's entire panel (but I don't think he has another EV).

In the second video, the installers split the woman's panel into two panels and only backed up one of them (most likely what would need to be done in our situations with multiple other EVs).

The part I'm wondering about is...let's say you currently have a 200A panel and you move 60A worth of circuits to a subpanel that doesn't need backup. Does that mean your main panel is now limited to 140A (200A - 60A), whereas previously your entire house had the flexibility of a 200A cumulative max?

 

[Gundo]

In our install, the Powershare only backs up the circuits we selected via a separate sub-panel, including well pump, oil furnace, air handlers, main refrigerator, select lighting circuits.

We didn't want our other EVSE, A/C compressors or other non-essential loads backed-up in order to extend the Powershare backup as long as possible

Here in Connecticut, we've had some lengthy 5 to 8 day outages, mostly in fall/winter/spring

YMMV

 

[eswimm]

There are 3 distinct installation methods I've seen based on people's posts, in order of lowest to highest costs.

Main Breaker Separation - Main panel becomes sub-panel of gateway.
Light Loads Backup - Gateway is sub-panel of main panel, up to 10 light circuits moved to gateway.
Heavy Loads Backup - Gateway is sub-panel of main panel, mix of light and heavy circuits moved to gateway.

There are (I believe) 10 slots available in the gateway for the 2 load backup options.

There are obviously some technical criteria that would dictate one of the load backup options, but I'm guessing there might also be state or local requirements that influence the configuration as well.

In my case, I have 2 200A panels and most of my high current loads are on the 2nd panel (HVAC, EVSE, Oven, Dryer, etc). My 1st panel contains mostly lights, outlets and such. There's still over 200A worth of breakers in the panel, but my typical whole panel load is 3-5kW.

My install will use the main breaker separation option, inserting the gateway between the main and my 1st panel, so the CT will backup the entirety of the 1st panel. Obviously, the CT could not support the full panel load if I was to intentionally plug in a high current load in every room in the house. That doesn't actually present a problem however, because the CT will automatically shut down powershare if it exceeds 11.5kW (48A). There's nothing technically wrong about a 200A sub-panel being fed through a 60A breaker, if the load could somehow exceed 60A, the breaker to the wall connector would trip, protecting the wiring. It can't actually do that though, since the CT will trip at 48A.

 

[mongo]

I found this thread from a few months back: https://www.cybertruckownersclub.co...teway-install-experience-and-explainer.17250/. It looks like the PowerShare gateway doesn't have any individual breakers, so it will only switch an entire panel that is external to it.

In the first video in that thread, the installers simply backed up the guy's entire panel (but I don't think he has another EV).

In the second video, the installers split the woman's panel into two panels and only backed up one of them (most likely what would need to be done in our situations with multiple other EVs).

The part I'm wondering about is...let's say you currently have a 200A panel and you move 60A worth of circuits to a subpanel that doesn't need backup. Does that mean your main panel is now limited to 140A (200A - 60A), whereas previously your entire house had the flexibility of a 200A cumulative max?

Gateway has an internal breaker panel.

To your question: your electrical service from the power company is likely limited to 200A. So moving 60A to another subpanel doesn't increase capacity on the main panel, same as if you feed that subpanel from a 60A breaker on the main panel.

 

[SentinelOne]

I have a 200amp main panel and just backing up the entire panel to help reduce install cost…figure in an outage we can manuall shut down usage or breakers to ensure dont overload….if we’re not charging the ev or doing laundry and only have 1 ac unit i assume should be good?

 

[mongo]

I have a 200amp main panel and just backing up the entire panel to help reduce install cost…figure in an outage we can manuall shut down usage or breakers to ensure dont overload….if we’re not charging the ev or doing laundry and only have 1 ac unit i assume should be good?

Probably.
We have 400A service (dual 200A panels) and can run the house off a 7kW genset with manual load shedding in winter in Michigan. Key is gas furnace and water heater. If you want AC, it really depends on the unit. Post a photo of its ratings plate for more info.
(Can't speak to whether they'll do your install that way though)

Sponsored