100 AMP electrical service in home, should I install Wall Connector Gen3?

[vct07]

Hi everyone,

I am pretty new to the Tesla world, and want to know if I should install Wall Connector Gen 3 for my Model Y. I just found my electrical panel is showing 100 on the fuse box. And my stove & heat are using gas and wash machine & dryer are electrical.

Hope to get some direction from you guys.

Thanks

 

[SkeetShooter]

You are going to be hard pressed to make this work. Generally a 200 amp service is recommended. Contact a local electrician.

 

[Velcade]

I would look at upgrading your service. 100 amp is quite old at this point.

 

[Sophias_dad]

You might not be able to get a full 48 amp setting on that wall connector, but your only real load is the dryer right now. The washing machine doesn't count for much.

A load calculation would dictate what you can get, but 32 amps wouldn't be unreasonable with what little data is available.

 

[LoudMusic]

I agree that 100 amp service is pretty low for modern equipment, but if you schedule your car to charge after midnight and make sure your dryer is done before then you'd probably be good to go.

 

[jcanoe]

The Tesla Wall Connector can be configured for use on any circuit from 15A up to 60A so you can install the Wall Connector on a dedicated charging circuit that fits your charging needs and does not exceed the available capacity of your home's 100A service. 60A may not be possible but your electrician can determine whether 50A/40A/30A/20A/15A can be added.

 

[Rocky_H]

I am pretty new to the Tesla world, and want to know if I should install Wall Connector Gen 3 for my Model Y. I just found my electrical panel is showing 100 on the fuse box. And my stove & heat are using gas and wash machine & dryer are electrical.

You are going to be hard pressed to make this work. Generally a 200 amp service is recommended. Contact a local electrician.

That is a really bad overgeneralization.
You can do a load calculation on your house with your home electrical service to find out how much spare amps of capacity you have to add a new circuit. Then you know how big of a circuit you can add. That has NOTHING to do with whether it's a wall connector or not. The wall connector is a configurable device, so even if you can only put in a 15 or 20 amp circuit, you could still put a wall connector on that if you want.

My house has a 125A main service, but my house is only 1600 square feet, so not all that large, and there was certainly room to add a circuit. People don't always need 200A service.

 

[Madsen203]

I have a 100a main and I use a 50a circuit for the WC No problem. I also have a hot tub and HVAC running on the same panel and never had it tripe be a problem. I get the full 42a charging without issue.

Not sure if you have to have it inspected or not but if you can install yourself, you’ll be just fine.

Increasing our service to 200 was going to cost like 15k as they had to move to main to bring it up to code and Jack hammer two driveways to run a new conduit line. I made the 100a service work and haven’t had a single issue.

 

[Midnightsun]

What seems to be the issue? A dryer typically draws 30amps and a wall connector maxed out is 48, still have 22a left over before popping a breaker assuming he is running the dryer at the same time. Lights, tv and other small stuff is fairly negligible so I see no problem. If ever there is a problem, you can always dial the wall connector down a bit to suit.

 

[Sophias_dad]

What seems to be the issue? A dryer typically draws 30amps and a wall connector maxed out is 48, still have 22a left over before popping a breaker assuming he is running the dryer at the same time. Lights, tv and other small stuff is fairly negligible so I see no problem. If ever there is a problem, you can always dial the wall connector down a bit to suit.

You are correct that the HPWC could be dialed down to make things better.

The problem with just adding 48 and 30 and saying its 22 less than 100, so no big deal is that a breaker isn't rated for continuous use at its rated capacity. In theory, that 100 amp breaker may well trip after a few hours at 81 amps, and that's well within the danger zone of 48+30.

Even if you accept that 100 amps is what can be delivered continuously, add a refrigerator during its defrost cycle(10A), a hair dryer(15A), microwave(10A), and maybe a window AC(10A) and you could be well over 100, especially if all those 120V loads happen to land on the same leg of the 240. TBH, even with all those temporary loads OP might be okay, because mild overload won't even trip a breaker quickly.

 

[SkyDog]

I have 100 amps to my house and just added a Tesla Wall Connector on a 40 amp breaker. I'm still waiting for my car so I haven't actually tested this yet, but a few electricians told me this will work fine.

The only other big electric appliances in my house are a dryer and a range/oven. I'll probably be charging the car at night when I'm not using much else in the house, so I really don't expect any problems.

 

[tlatxm3]

That is a really bad overgeneralization.
You can do a load calculation on your house with your home electrical service to find out how much spare amps of capacity you have to add a new circuit. Then you know how big of a circuit you can add. That has NOTHING to do with whether it's a wall connector or not. The wall connector is a configurable device, so even if you can only put in a 15 or 20 amp circuit, you could still put a wall connector on that if you want.

My house has a 125A main service, but my house is only 1600 square feet, so not all that large, and there was certainly room to add a circuit. People don't always need 200A service.

Hi, my house has the same 125A max. I only need to charge the car in the midnight and the appliance being using at the same time are refrigeator and AC. Which amps breaker should I add, 60/50/40? Thanks in advance.

 

[SkyDog]

I have 100 amp service to my house. From that, I added a 60 amp sub panel in my detached garage, and I have the Wall Connector on a 40 amp circuit. I've been using this setup for over 4 months and it works fine - no problems at all. My only other 'big' electric appliances are a dryer and an oven/range. I usually plug in to charge in the evening, so I've never been charging while using the dryer or the oven.

Shop around and get a few estimates. Initially, I didn't think I'd be able to get a WC with only 100 amps to the main panel, but most electricians said I could do this without problems, and recommended either a 50 or 60 amp subpanel in the garage. I had one electrician tell me that a sub panel wouldn't make sense, and he wanted to wire the WC to my main panel on a 20 or 30 amp circuit. This guy was on Tesla's list of recommended electricians and I think he gave me the worst advice of all. So get a few electricians out for a look!

 

[CDNMYP]

The Tesla Wall Connector can be configured for use on any circuit from 15A up to 60A so you can install the Wall Connector on a dedicated charging circuit that fits your charging needs and does not exceed the available capacity of your home's 100A service. 60A may not be possible but your electrician can determine whether 50A/40A/30A/20A/15A can be added.

This.

I have 100A service and went the safe route and got a 30A circuit installed (which charges at 24A). I still get 7-8% per hour of charge so unless you drive 200+ miles per day, charging overnight with a 30A circuit will be plenty. Given that your stove and heat use Gas, 30A should be no problem. You could maybe even do 40A. Get an electrician to do a load calculation.

 

[Rocky_H]

Hi, my house has the same 125A max. I only need to charge the car in the midnight and the appliance being using at the same time are refrigeator and AC. Which amps breaker should I add, 60/50/40? Thanks in advance.

I can't give you an answer on that. The second line of my comment that you responded to said:

You can do a load calculation on your house with your home electrical service to find out how much spare amps of capacity you have to add a new circuit. Then you know how big of a circuit you can add.

Load calculations look at things like the square footage of your house, to account for general things like lighting and wall outlets. So I don't know if you have a 1,000 square foot house, or a 5,000 square foot house. Maybe you have three jacuzzis that have heating pumps. I don't know, so I can't give you some specific number. There are load calculation forms online. Go fill one out and see what it shows.

It should show how many amps are basically already accounted for as "used" and then have some number leftover showing how many amps are still available. If it shows 33.6 amps still free, then sure, you could add a 30A circuit.

 

[archae86]

I got my model Y about three months ago. Eager to "do the right thing" I bought a Wall Connector and attempted to contact a Tesla approved electrician to install it. When they learned I had a 100 amp breaker they did not want to do the job, saying I would need a new main panel and a utility service upgrade. I got an independent electrician to do the job. He indeed installed a new main panel, and upgraded the wiring from the utility input point to that box.

So I have a 60 amp breaker for my Wall Connector, which means I could leave it configured to the 48A maximum (80% of 60). But in fact, I choose to leave it set to 40A maximum, just to give a little extra margin. Even at that reduced level I am nearly always finished charging before midnight.

As my electrician charged me about $3400 (and I supplied the Wall Connector) I now think I could have had a highly satisfactory solution at least two other much cheaper ways.

1. I could have skipped the Wall Connector altogether, gotten a 240V outlet installed on a pair of 20A breakers which were already paired to supply an unused 20A 240V circuit, and bought the required extra cord for my mobile connector to use the particular 240V socket chosen. I think that would have saved me over $3000, and still given me overnight charging.

2. I could have bought the Wall Connector, gotten an electrician to connect it to a 20A 240V circuit as above, and set the Wall Connector maximum to 16A. Again that would have given me overnight charging, saved me far over $2,000, and I'd not have been wearing out the Mobile connector.

Before you go to thousands of dollars to upgrade service and main panel, ask yourself how much difference a home charging rate of 48A/240V vs. one of 16A/240V practically makes for you, and consider saving a good bit.

 

[Rocky_H]

2. I could have bought the Wall Connector, gotten an electrician to connect it to a 20A 240V circuit as above, and set the Wall Connector maximum to 16A. Again that would have given me overnight charging, saved me far over $2,000, and I'd not have been wearing out the Mobile connector.

I suppose it's a little unusual for EVSE equipment in the industry, so maybe that's why a lot of electricians don't know that the Tesla wall connector is a variable setting device. It doesn't have to have a 60A circuit to use it. For situations like yours, with a small house electrical service, installing it on an existing 240V 20A circuit and setting it for that level is a very good use case.

 

[samps]

I have a 100amp service in a 41y old house and really wanted a wall connector. I looked into upgrading to a 200amp service and although the costs from the utility provider are relatively low, due to the size of the lot and adjacency of the building to the PL, it would have cost too much. I decided to rejig some of the wiring and used a neocharge with our 240V dryer with the UMC to get 24A, 240V charging, which is more than enough for us. Something to consider if upgrading to a 200amp service is not practical.

 

[ATPMSD]

A lot of great advice!

I suggest you start by defining what you need. You may find the standard 120v/20a garage outlet is all you need. Or, if a 240v/20a outlet will do the job (NEMA 6-20), it is easy to convert a dedicated 120v/20a outlet into a 240v/20a outlet. So I suggest you start with the table you can find here, but use it conservatively.:

Gen 2 NEMA Adapters

Use a variety of household outlets to charge your Tesla with a Gen 2 NEMA Adapter. Simply attach the appropriate adapter to your Mobile Connector, plug into the corresponding outlet and begin charging. Adapter Max Distance Gained Per Hour of Charge Model S Model 3 Model X Model Y 5-15 3...

shop.tesla.com

If you need more, a wall connector installation is cheaper then an outlet for a mobile connector. Just configure it for whatever amperage you install. BTW, if you are handy you can determine the available load on your own. You will need one of these:

Klein Tools 400 Amp Digital Clamp Meter, AC Auto-Ranging with Temp CL220 - The Home Depot

The CL220 measures AC current and NCVT via clamp and AC/DC voltage, resistance, and continuity via test-leads, and temperature with thermocouple. The meter features automatically ranging True Root Mean

www.homedepot.com

Warning: do not do the following if you are all uncomfortable!!!
Open the breaker box and turn everything in the house on. Use the meter to measue the load on each of the two mains (warning: they are ALWAYS hot). Add the two values together. Now subject the total from 80-amps (100-amp service times 80%). The answer is the maximum continuous load you can add. Multiple this number by 125% and this is the circuit you can run.

If you use something larger you will need to manage the load.

 

[tlatxm3]

I can't give you an answer on that. The second line of my comment that you responded to said:

Load calculations look at things like the square footage of your house, to account for general things like lighting and wall outlets. So I don't know if you have a 1,000 square foot house, or a 5,000 square foot house. Maybe you have three jacuzzis that have heating pumps. I don't know, so I can't give you some specific number. There are load calculation forms online. Go fill one out and see what it shows.

It should show how many amps are basically already accounted for as "used" and then have some number leftover showing how many amps are still available. If it shows 33.6 amps still free, then sure, you could add a 30A circuit.

Thank you. I will try to get it and share with later.