Charging at home

[drj400m]

New member so trying to jump in. I am currently looking at buying a MS and I have a question about charging set up at my home.
My current home circuit breaker has a door sticker stating max is 125 amps and I have the main breaker (2 breakers together with plastic showing 100 on each) that from what I can gather is 200 amps. So I’m unsure if breaker is 125 or 200.
Question is: can a 125 amp circuit breaker handle a NEMA 15-40 addition? I would have an electrician do the work (I am sure by the question you can tell not electrically inclined).
I have read that the actual circuit breaker it uses is a 50 amp.
Thank you in advance of you answers!
I look forward to learning about the MS here on these forums.

 

[brkaus]

2 together is still 100.

If it can handle a 50a breaker, that’s a different question. What other loads are in your house?

Also, how many miles do you drive per day, average & max?

 

[drj400m]

I have a washer, dryer (normal plug) and microwave and refrigerator. The stove, furnace and water heater is gas. It’s a smallish townhome.
I drive on average 30 miles per weekdays and 60 miles per day on weekends.
In my mind I think 23 miles/hr charge is possible if I’m reading the charts right.

 

[Lloyd]

New member so trying to jump in. I am currently looking at buying a MS and I have a question about charging set up at my home.
My current home circuit breaker has a door sticker stating max is 125 amps and I have the main breaker (2 breakers together with plastic showing 100 on each) that from what I can gather is 200 amps. So I’m unsure if breaker is 125 or 200.
Question is: can a 125 amp circuit breaker handle a NEMA 15-40 addition? I would have an electrician do the work (I am sure by the question you can tell not electrically inclined).
I have read that the actual circuit breaker it uses is a 50 amp.
Thank you in advance of you answers!
I look forward to learning about the MS here on these forums.

You need to have someone qualified to do a load analysis for you.

 

[Need]

When I had our outlet install, I contacted local electrician. He had me take a few picture of the main panel, asked me how far away I want the outlet, and gave me a quote within minutes after he got the MMS of the pics.

 

[budosteve]

You have 100a single phase service, and based only on your description you have the capacity to add a double pole 50a breaker.

Based on your planned energy consumption you can easily charge at 30a if you’re concerned about current draw.

LMK if you need to talk it out; happy to help.

Is your breaker panel within close proximity to your garage?

 

[CameronB]

You need to have someone qualified to do a load analysis for you.

Yeah, get a load analysis. If you have a 200 amp panel, likely there's some decent capacity available. If you have a 125amp panel, then likely will be tighter to try to find 'room' for a new 50A circuit. But...it all depends on the appliances, lights and other usage (say like a pool) you have. But it's also all the things you have plugged into all your outlets, not just classic appliances but also computers, stereos, TVs, etc. If you have a lot of incandescent or halogen lights..those use a lot more energy than if you had all LED lighting, for example. Energy Star appliances vs older, less-efficient ones, etc.

An electrician can do this for you pretty easily. Some do it more accurately than others. Mine was very detailed and wanted a full listing of what devices were used. In my case, I wanted to do a 90amp circuit - totally overkill and $$$. I did it for future proofing and maybe it will eventually be useful, but like you, I typically drive about 30-50 miles a day. I have a HPWC and although yes, even with the 'overhead' it could use the 72A that is the current max for any newish Tesla (though there were some classic ones that could handle 80A). Most Tesla's max out at 48A, but that's still plenty fast.

There are people more well versed in all the EV math than I am, but I believe your NEMA 15-40 on a 50A circuit (needed to get the full 40A because of overhead) would give you about 25ish miles per hour of charge.

With a High Performance Wall Charger (HPWC) at 48A, you would get about 32ish miles per hour of charge.

Even if you end up installing a 40A circuit (because not room for 50) and charging at 32A, it still means you'll recover your daily 30 miles in a few hours while you sleep.

 

[2002A]

I had the approved Tesla installer come out and give me an estimate before I ended up installed my 15-40 receptacle myself He looked at my electrical panels and the info tag inside the oven in the kitchen and was able to tell me per the app on his smartphone that I was OK for a 50 amp breaker. I got a few more estimates and after talking with the electricians I just decided to do it myself with about 85 dollars of materials. So I am running 240 volts with 40 amps on my 15-40 receptacle with a stainless steel cover. I get between 36 and 38 miles per hour on my 2016 90D.

 

[drj400m]

Thank you for all the replies. This truly is helpful. I was somewhat down yesterday as I had thought that the “dream’ was over because I wasn’t going to be able to charge at home.

BTW budosteve I am having the plug within feet of the box. My box is currently in the garage on the left. Right where I would want to put the plug.

 

[Brass Guy]

You have a huge advantage that your larger appliances are gas. If you have central AC, I think that's usually a 30A 2-pole. That would be a big factor in your load calculation. If you don't have AC, it is very likely you'll be fine adding a 14-50.

My house has a 100A service, no AC, and gas water heater, stove and drier. I added the 14-50 to that.

I don't think they use 100A panels in any new construction any more; 200 or even 400 are more common now.

 

[drj400m]

Also, not sure this matters, I have a 1700 sq/ft townhome. My energy consumption per Excel is lower than “efficient” neighbors by quite a bit.

 

[drj400m]

Brass Guy I do have AC in the townhome.

 

[brkaus]

I have a washer, dryer (normal plug) and microwave and refrigerator. The stove, furnace and water heater is gas. It’s a smallish townhome.
I drive on average 30 miles per weekdays and 60 miles per day on weekends.
In my mind I think 23 miles/hr charge is possible if I’m reading the charts right.

Photo of your existing breaker panel?

It sounds very feasible and even if you have to go down to 30a breaker, you can charge at 24a and still get back 15-20 miles per hour of charging.

I would recommend an electrician if you have never worked with electricity before.

 

[Brass Guy]

Brass Guy I do have AC in the townhome.

As others stated, have a load calc done. It may be close. But you should be able to add some size of 240V circuit, as long as there's physical space in your panel.

 

[drj400m]

FBF74707-EF4C-44DD-BA40-EBA8176CD9D0

• drj400m
• Feb 4, 2018

226AD72C-F2DB-4977-8E36-2C0402C1EBFC

• drj400m
• Feb 4, 2018

Here’s my existing panel. I just hope this can work.

 

[brkaus]

You mentioned gas water heater, but there is a breaker for water heater?

On the surface, looks to me like you easily have capacity. Exactly how much, I’m not sure.

 

[drj400m]

As stated above not electrically inclined. You are correct brkaus

 

[brkaus]

You’re likely looking at about $50-80 in parts. Perhaps $150-300 labor. Plus permit if you go that route.

I’d call at least 2 electricians.

 

[budosteve]

Thank you for all the replies. This truly is helpful. I was somewhat down yesterday as I had thought that the “dream’ was over because I wasn’t going to be able to charge at home.

BTW budosteve I am having the plug within feet of the box. My box is currently in the garage on the left. Right where I would want to put the plug.

This is easy then. Very affordable. If you’re adventurous you can do it yourself.

 

[BerTX]

You’re likely looking at about $50-80 in parts. Perhaps $150-300 labor. Plus permit if you go that route.

I’d call at least 2 electricians.

And don't tell them it is to charge a Tesla. The estimate goes up.