Adding a breaker to Tesla Energy Gateway for Wall Connector

[loan-potato]

I am getting a new circuit installed for my Wall Connector to charge my Model Y.

Both my main panel and sub panel are full. In my Energy Gateway there are currently 2 breakers installed. A 100 Amp going to my main panel, and a 15 AMP labeled as spare. My plan was just to use this spare 15 Amp breaker for the wall connector. 15 Amp @ 220V would be more than enough for my driving needs. When I had the electrician out the other day for an estimate, he said there is a third open breaker slot in the Energy Gateway and he wants to install a 60 Amp breaker there. The main breaker in the energy gateway is 150 AMP, so having a 100 Amp and 60 Amp seems like I would run the risk of tripping the main breaker.

My other thought is that if I was charging at 60 Amp, the ac was running and I had the oven on, and the power went out, I’d overload my 3 Powerwalls. Guess I could always go with the 60 Amp and just provision the wall connector at a lower amperage.

I have another electrician coming by tomorrow, so I will see what he recommends. Both of the electricians are Tesla certified. However I don’t think they have much experience with the Tesla Energy products.

 

[Vines]

I am getting a new circuit installed for my Wall Connector to charge my Model Y.

Both my main panel and sub panel are full. In my Energy Gateway there are currently 2 breakers installed. A 100 Amp going to my main panel, and a 15 AMP labeled as spare. My plan was just to use this spare 15 Amp breaker for the wall connector. 15 Amp @ 220V would be more than enough for my driving needs. When I had the electrician out the other day for an estimate, he said there is a third open breaker slot in the Energy Gateway and he wants to install a 60 Amp breaker there. The main breaker in the energy gateway is 150 AMP, so having a 100 Amp and 60 Amp seems like I would run the risk of tripping the main breaker.

My other thought is that if I was charging at 60 Amp, the ac was running and I had the oven on, and the power went out, I’d overload my 3 Powerwalls. Guess I could always go with the 60 Amp and just provision the wall connector at a lower amperage.

I have another electrician coming by tomorrow, so I will see what he recommends. Both of the electricians are Tesla certified. However I don’t think they have much experience with the Tesla Energy products.

Likely the 100A and 60A breakers would be fine with a 150A main breaker protecting them. Most people charge cars during periods of low load, and most people don't trip the 100A breaker feeding their house loads. If you do find yourself already tripping this 100A breaker, then there might be an overload possibility.

If you have a Tesla charging, there is a setting in the app that will allow you to set a threshold where the car will not charge while off grid.

 

[loan-potato]

Yeah I think you are right. The highest utilization I’ve ever seen on my Energy Gateway is 9.5kW, which it is about 43 Amps. So that should leave plenty of room. Another thing I can do is set the car to charge late at night when the dryer and oven are unlikely to be on.

 

[Ramphex]

Also consider that the wall charger at full power only pulls 48amps. 60amp breaker is with the required 20% overhead for compliance.

 

[jboy210]

You might consider if you need to really need to charge at max rate. If you are going to come home and charge at night than even a lower circuit may be enough. And it is also easier on your Powerwall + grid energy budget. We have two Teslas and get by just fine with a 40A circuit and a one wall charger.

 

[Ramphex]

Yea 40amp breaker will give you 32amps at 240v, plenty to charge from empty to full overnight.

 

[tfan2018]

I installed a charger on my dryer circuit.. 24A 240V is enough so anything above that is even faster!

 

[hmcgregoraz]

Labor vs materials costs.

The labor to install a 60amp, a 50amp, or a 40amp breaker and associated wire are almost identical. Generally the cost of the breaker between 40, 50, and 60 amp are nearly identical (60 may be a bit more depending on the mfg), the wire will be a the biggest diff in cost, and it depends on how long the run is.

Personally I would install the wire and the breaker for the wall connector to be on a 60amp breaker, with a 48amp load, and then lower it in the car via software to what fits your needs best most of the time. The large wire will result in less voltage drop when not pulling the full 48amps, though that is probably noise when it comes to the diff in charging cost.

Our electric rates are such that we are best off charging directly from solar vs the grid in Tucson, and I adjust our charging to stay within that range most of the time.

There are some times where we want to get charged up quickly, and I will accept that I need to pull from the grid a bit, and I will bump it up to 48 amps in the app.

As @Vines stated, the 60amp breaker + 100amp breaker are basically at zero possibility of tripping the 150amp breaker. Power walls are rated at 5KW continuous, 7KW peak each, or 15/21KW, or 62.5amp/87.5amp at 240V. Again, I would use the app to control if you charge while off grid.

Having the ability to charge when off grid is a good idea, as then if you produce more solar than your power walls can soak up when off grid (let's say a multi day outage), you have somewhere you can put it. Most of the time you would not want to charge when off grid.

Our plan is to have two of our three charging spots on the backup side of our install, and 1 charging spot not on the backup side. Of course our powerwalls are backordered, and won't be able to be installed for about 11 months...

-Harry

 

[loan-potato]

I ended up going with the electrician that recommended the 60 Amp circuit. In fact he is coming by tomorrow to install it.

I had two other electricians recommended a 30 and 40 Amp circuit. The electrician that recommended the 60 Amp circuit showed the most confidence in dealing with the Tesla system, which is why I picked him.

I figure I’ll have them provision the wall connector at 60/48 Amp and then just turn down the charge rate in the car. It will be nice to have the higher rate available for the times that I need it.

 

[Ramphex]

I ended up going with the electrician that recommended the 60 Amp circuit. In fact he is coming by tomorrow to install it.

I had two other electricians recommended a 30 and 40 Amp circuit. The electrician that recommended the 60 Amp circuit showed the most confidence in dealing with the Tesla system, which is why I picked him.

I figure I’ll have them provision the wall connector at 60/48 Amp and then just turn down the charge rate in the car. It will be nice to have the higher rate available for the times that I need it.

And you can always login to the charger portal yourself and change it to whatever amperage below 48, if for whatever reason you want to do that. It’s a simple drop box setting.

 

[Vines]

And you can always login to the charger portal yourself and change it to whatever amperage below 48, if for whatever reason you want to do that. It’s a simple drop box setting.

For people who really need to limit the amperage of their Gen 3 HPWC circuit I agree with this.

Changing it in the car works as well, but as soon as you invite a friend over to charge or get a 2nd EV it is so easy to forget that the lower charge setting is local to the car.

 

[loan-potato]

The electrician came out today to run the circuit and install the wall charger. They were quick only took a little over an hour. They took the 15 Amp spare breaker out of the energy gateway and put a 60 amp in. I expected them to have some trouble getting the wire across my attic since I have 18 inches of insulation up there. I never heard them climbing around up there. Guess they used one of the extendable fiberglass poles to push the wire across.

We plugged the car in and it charged at 48 amp. I went ahead an turned the car down to 20 amp, so that I would stay under the Powerwall limit if I have everything going.

I tired to log into the web UI for the wall connector, but it never finishes loading. It shows a picture of the power wall and the serial number, but the loading icon stays. So guess I’ll leave it provisioned at 60/48 amp and just turn it down in the car. That would make it easier to turn it back up if I‘m in a hurry anyway.

 

[wwhitney]

They took the 15 Amp spare breaker out of the energy gateway and put a 60 amp in.

It's a little unusual to put a load breaker in the Gateway. What are the other breakers there (size and what's connected)?

Cheers, Wayne

 

[Ramphex]

The electrician came out today to run the circuit and install the wall charger. They were quick only took a little over an hour. They took the 15 Amp spare breaker out of the energy gateway and put a 60 amp in. I expected them to have some trouble getting the wire across my attic since I have 18 inches of insulation up there. I never heard them climbing around up there. Guess they used one of the extendable fiberglass poles to push the wire across.

We plugged the car in and it charged at 48 amp. I went ahead an turned the car down to 20 amp, so that I would stay under the Powerwall limit if I have everything going.

I tired to log into the web UI for the wall connector, but it never finishes loading. It shows a picture of the power wall and the serial number, but the loading icon stays. So guess I’ll leave it provisioned at 60/48 amp and just turn it down in the car. That would make it easier to turn it back up if I‘m in a hurry anyway.

That’s probably because you’re connecting to it over your WiFi. Connect to its own actual SSID and the rest of the settings will load.

 

[loan-potato]

That’s probably because you’re connecting to it over your WiFi. Connect to its own actual SSID and the rest of the settings will load.

Yep I was connecting to it over my WiFi. I’ll give it a try using its SSID.

 

[loan-potato]

It's a little unusual to put a load breaker in the Gateway. What are the other breakers there (size and what's connected)?

Cheers, Wayne

Just the 100 amp breaker that goes to my main panel. My main panel is full which is why they suggested putting it in the Gateway.

 

[Ramphex]

Just the 100 amp breaker that goes to my main panel. My main panel is full which is why they suggested putting it in the Gateway.

Am I missing something here

 

[wwhitney]

Just the 100 amp breaker that goes to my main panel. My main panel is full which is why they suggested putting it in the Gateway.

So presumably you have a separate generation panel? What breakers are in it? And what size is your main service disconnect?

Cheers, Wayne

 

[Jones1]

What are the benefits of installing a Tesla Wall connector from your Tesla Gateway?
Is this a better way to go? Versus the home breaker box? I want to put a wall connector outside. I see that some people have installed theirTWC at the gateway breakers. I figured it may be cheaper. Less wire for the run.
Is this the location that people are using. The empty slot?

 

[Ramphex]

What are the benefits of installing a Tesla Wall connector from your Tesla Gateway?
Is this a better way to go? Versus the home breaker box? I want to put a wall connector outside. I see that some people have installed theirTWC at the gateway breakers. I figured it may be cheaper. Less wire for the run.
Is this the location that people are using. The empty slot?
View attachment 999821

In theory you can do it to avoid putting a hole in the wall back into your house if your connector is going to live outside. I would recommend not doing it if you’re ever going to expand your array with more panels though.