80A Breaker installed

[AlanSubie4Life]

Can I do it or should an electrician do it?

If you know how to throw the breaker, have the special bit and the appropriate screwdriver handle to accommodate the bit, along with the instruction manual, then it should be fine. However, if you are not certain of what you are doing (it should seem very straightforward), you should probably contact whoever installed your HPWC.

 

[RScottyL]

With the 80A breaker, if you get a second Tesla vehicle in the family, you can install another Wall Mount EVSE and daisy chain them!

 

[john85775]

I’m in this very predicament now — deciding between a single load-shared breaker for two chargers or two independent ones.

In order to do the full 80 amp on the Tesla charger, manual says it needs a 100 amp breaker.

The cost to run that size wiring is exponentially more than simply doing two independent 48 amp ( 60 amp breaker ) circuits/lines.

While I love the future-facing aspect of a full 80 amps, but the reality is two independent 48 amp chargers is a better (and more resilient) setup vs a load-shared one.

 

[davewill]

... While I love the future-facing aspect of a full 80 amps, but the reality is two independent 48 amp chargers is a better (and more resilient) setup vs a load-shared one.

Of course it is, at least for the cars being delivered now. Load sharing makes sense in two basic scenarios:

1. Your panel can't supply enough current for two independent 32a or 48a wall connectors.
2. You already have one circuit and don't want to pay to run a second all the way from the panel.

 

[john85775]

Of course it is, at least for the cars being delivered now. Load sharing makes sense in two basic scenarios:

1. Your panel can't supply enough current for two independent 32a or 48a wall connectors.
2. You already have one circuit and don't want to pay to run a second all the way from the panel.

Makes sense. We are replacing our panel as part of a large upgrade, including a couple Powerwalls. So in our case, clean slate for charging infrastructure.

 

[davewill]

I left one scenario out. If you had one of the older cars that had either 72a or 80a charging on board, then doing a shared 100a circuit would let those cars charge at full rate if they were alone.

 

[Big Earl]

While I love the future-facing aspect of a full 80 amps, but the reality is two independent 48 amp chargers is a better (and more resilient) setup vs a load-shared one.

It really depends on how much energy you need between the two vehicles and how much excess capacity you have available in your panel and on the transformer feeding your house (and any others that might share your transformer).

 

[Chef Brian]

Okay, so I got the correct tool to open the cover and adjusted it to the “B” which corresponds to the 80A breaker. And Success!!!

But! Later that day while my car was charging my main breaker for the panel tripped and cut power to everything! To be fair I was running the AC the microwave and the dryer and charging the car at the same time... does this sound normal? Would reducing the dial to the 60A setting have avoided this?

 

[Kirby64]

Okay, so I got the correct tool to open the cover and adjusted it to the “B” which corresponds to the 80A breaker. And Success!!!

But! Later that day while my car was charging my main breaker for the panel tripped and cut power to everything! To be fair I was running the AC the microwave and the dryer and charging the car at the same time... does this sound normal? Would reducing the dial to the 60A setting have avoided this?

Yes, that sounds pretty normal. Reducing the dial to 60A won't do anything. You're still drawing 48A max from the car. If you dial is even lower, it may help, but obviously you charge slower so you have a longer period of time where you have to worry about tripping stuff.

Assuming you have a 100A main breaker, running AC, dryer, microwave, and car charger would use roughly this much current:
AC: 32A (at 240V)
car: 48A (at 240V)
dryer: 24A (at 240V)
microwave: 12A (at 120V)

Add that up and you're way over a 100A main breaker (which I assume is the main breaker current). That doesn't count any of the other current on any other circuits, either.

If you frequently run AC, dryer, microwave, and charge the car at the same time, you should likely look into upgrading your main breaker capacity. It's not good to use that much load constantly. Otherwise, just try not to run the dryer at the same time as charging the car. Shouldn't be that hard to coordinate.

 

[Big Earl]

Okay, so I got the correct tool to open the cover and adjusted it to the “B” which corresponds to the 80A breaker. And Success!!!

But! Later that day while my car was charging my main breaker for the panel tripped and cut power to everything! To be fair I was running the AC the microwave and the dryer and charging the car at the same time... does this sound normal? Would reducing the dial to the 60A setting have avoided this?

What size is your main breaker? Also, what size is the transformer feeding your property?

You put a lot of load on it all at once. I suggest not charging the car at full speed at the same you’re using a bunch of other high load appliances. If you have to do all of that simultaneously, slow the car down via the touch screen. If you regularly do all of these activities together, you might want to consider dialing the wall connector down to a lower setting.

Our house has a pretty small feed, so my general rule is to only charge as fast as I need to. Overnight, I’ll set the car at 24 to 30 amps. If I need to add range quickly on a lunch break or something, I’ll crank it up to 40 amps. I monitor voltage and use that as a rough gauge of available overhead. Our transformer powers seven houses, so looking at voltage gives me an idea of how much power the neighbors are using.

 

[Dmagyar]

Okay, so I got the correct tool to open the cover and adjusted it to the “B” which corresponds to the 80A breaker. And Success!!!

But! Later that day while my car was charging my main breaker for the panel tripped and cut power to everything! To be fair I was running the AC the microwave and the dryer and charging the car at the same time... does this sound normal? Would reducing the dial to the 60A setting have avoided this?

The main breaker on your house did it’s job, your service capacity, is who knows? The setting of what you’re charging your car at is the least of the difficulties facing you. Whomever you hired for the install, assuming you paid someone, is they should’ve done a load calc for your service to see how viable adding (80) 64 amps additional load would “fly”, the main did the calc for you, it failed...Suggest you determine the capacity of the main, which tripped, WAG I would say (your supply is) is either 100, or 125 (maybe smaller) depending on the age of your home. Convincing your family to forgo A/C so you can charge the car will be a tough sell, at least during the summer.

 

[davewill]

I think you need a good electrician to evaluate the panel. If you blew the main breaker, you are either seriously over capacity, or there's something wrong with that breaker. You need a expert to figure out whether there is something wrong, and otherwise do a proper load calculation to determine what the max size of the new circuit SHOULD have been (if it can accept a new 240v circuit at all) and then change the breaker (and wall connector config) to that correct maximum. Dialing down the wall connector is not enough by itself.

It's not inconceivable that you would need to upgrade your panel or service.

What you don't want to do is just trial and error your way to something that "works".

 

[AlanSubie4Life]

I think you need a good electrician to evaluate the panel. If you blew the main breaker, you are either seriously over capacity, or there's something wrong with that breaker. You need a expert to figure out whether there is something wrong, and otherwise do a proper load calculation to determine what the max size of the new circuit SHOULD have been (if it can accept a new 240v circuit at all) and then change the breaker (and wall connector config) to that correct maximum. Dialing down the wall connector is not enough by itself.

It's not inconceivable that you would need to upgrade your panel or service.

What you don't want to do is just trial and error your way to something that "works".

Maybe the electrician used the 15A/12A setting for a reason! Though that would not have been the right thing to do, I could see him adding the requested correct gauge wire to support a high current 80A setting "in the future" when the panel is replaced...but then dialing it back to what the current service could handle according to his load calcs. But not sure why he would have installed an 80A breaker in that case (again, it could have been to save money in "the future"). Also 15A/12A seems too low to come out of any load calcs. Though the main breaker did blow...so...who knows, without pictures.

All of this would be terrible of course. But with electricians these days, who can really say? It's hard to even get a ground connected when you really need one!

 

[Rocky_H]

But! Later that day while my car was charging my main breaker for the panel tripped and cut power to everything! To be fair I was running the AC the microwave and the dryer and charging the car at the same time... does this sound normal? Would reducing the dial to the 60A setting have avoided this?

I just looked through this whole thread of your comments, and I don't ever see you mentioning what size main breaker you have. And seeing as how you were only drawing up to 48A with the car, plus other loads in the house, I'm thinking it's probably pretty small, which leads me to my next question:

Whomever you hired for the install, assuming you paid someone, is they should’ve done a load calc for your service to see how viable adding (80) 64 amps additional load would “fly”,

Who in the world thought it would be OK to put an 80A breaker in?! Did anyone do a load calculation? You weren't even near fully utilizing it, and it overloaded your entire house supply. 80A is probably way bigger than what you legitimately should be allowed to have there.

The main for my house is 125A, and there's no way I would have considered being able to put in an extra 80A circuit. I did a 50, which I primarily use at night.

 

[Chef Brian]

I just looked through this whole thread of your comments, and I don't ever see you mentioning what size main breaker you have. And seeing as how you were only drawing up to 48A with the car, plus other loads in the house, I'm thinking it's probably pretty small, which leads me to my next question:


Who in the world thought it would be OK to put an 80A breaker in?! Did anyone do a load calculation? You weren't even near fully utilizing it, and it overloaded your entire house supply. 80A is probably way bigger than what you legitimately should be allowed to have there.

The main for my house is 125A, and there's no way I would have considered being able to put in an extra 80A circuit. I did a 50, which I primarily use at night.

A lot of this conversation is over my head, but here are a few pictures of my box before the electrician installed the 80A Circuit. Does this add any valuable information?

 

[Big Earl]

A lot of this conversation is over my head, but here are a few pictures of my box before the electrician installed the 80A Circuit. Does this add any valuable information?

Which breaker tripped? Also, where did your electrician install the 80? Can you post a pic of it currently?

 

[brkaus]

Which breaker(s) tripped? I’m not seeing a main breaker in that panel?

edit - oh, that’s one of those panels with the main breakers at the top and one feeds the bottom smaller breakers?

 

[Chef Brian]

Which breaker(s) tripped? I’m not seeing a main breaker in that panel?

edit - oh, that’s one of those panels with the main breakers at the top and one feeds the bottom smaller breakers?

Red Arrow is the one that tripped and cut power to everything. Blue arrow is where the new 80A was installed.

 

[brkaus]

Agree with @Big Earl

can you get a closer picture of that square d label? And is there a diagram on the back of the door?

where is the panel fed from? Meter? And is there a breaker at the meter?

 

[Big Earl]

I’d call the electrician back. Looks to me like he had no business adding an 80 amp circuit to that panel. If the 60 that tripped is feeding the location that powered the 80, then no wonder it doesn’t work. That panel, like mine, appears to have two sub sections that are fed by a pair of 60 amp mains. I’d need to get a closer look at the panel to make a recommendation beyond just calling the electrician. Shoot me a PM if you want another set of eyes on it and I’ll make some time to stop by and check a few things out.

For now, set your car to 24 amps on the screen and you should be good.