Charging with 110

[cduzz]

Thanks for the replies. We have a 220 volt and I bought the adapter but were only intending on using that for a backup. I don’t drive a lot and I have time and we just thought I’d always use the supercharger .5 miles from my house. From what I’m reading this is bad for the battery? Is that correct? It is better for the battery to constantly charge at home right?

• nobody actually knows which is better (fast DC charging or medium speed l2 charging or super slow l1 charging. Tesla probably knows more than most people, but even they are still learning.
• DC Fast charging needs to heat the batteries up to the top end of their stable temperature, but the batteries spend way less time in "charging mode"
• Slower charging puts the batteries in "charging mode" for far longer and it may be that the charging mode of a battery, especially at incorrect temperatures, harms batteries.
• None of this likely matters to you or your car -- it is mostly an actuarial exercise for enterprises that mange large fleets of batteries who are trying to squeeze an extra 0.01% of reliability out of their fleets of millions of batteries.
  
  As the saying goes "Those who know don’t talk. Those who talk don’t know."

What actually matters to you? Maybe money? I assume you pay for your electricity. The car has 2 sources of charging friction -- one is the transformers to take the 12a/120v input and bring it up to 400v the other is the battery heater. You always pay the conversion charge and pay for the heating charge in the winter. If you're you're spending 20-50% of your power just getting the battery ready to charge, not actually putting range into your battery, you're spending 20-50% more money charging your car than you need to. It gets even worse if you have time-of-use charges from your utility -- they will charge you more for power pulled out of the wall at peak times and less at low load times; having a 50a charging circuit lets you pump all your electricity into your car in the low cost window.

Another potential concern with charging on a standard 120 outlet is that you may not be charging on a dedicated circuit. The way an electric car interacts with the house is very different from any other appliance in a house; it will attempt to draw 80% of the maximum power from the circuit for hours at a time. Let's say that plug happens to be shared with a television or a stereo or a toaster or a water heater or some other appliance? If you run one or the other, everything's fine, but if you happen to be charging the car and make a pot of coffee, you may occasionally trip the breakers. This tends not to be the case with 240v circuits (in the USA) because those almost always are dedicated circuits between that one outlet and the breaker. Also, having lived in old houses my whole life, I would be somewhat skeptical of the reliability of a random outlet and I would want to assess the health of the in-wall wiring for a proposed EV charging setup. I would not bet on setups aren't actually charging a tesla thousands of hours a year on 60 year old outlets and wires using 40 year old circuit breakers...

Lastly -- a supercharger isn't really a good replacement for home charging -- according to the tesla-doesn't-advertise from tesla you may spend an hour once a week if you drive 200 miles in a week. In reality you'll have to charge 2-3 times and if you drive that little your battery will always be way below the peak charging threshold, so you'll be spending almost 2 hours to go from 20% to 90% and wasting the first part of the supercharging which should be super fast instead heating the battery. So you may be thinking you'll spend a relaxing hour at the supercharger once a week; in reality you'll be spending 3-6 hours per week if you're only supercharging, at least if you're supercharging an older S on a cold battery.

Supercharging is awesome for traveling long distances, but when you're driving long distances it is very likely your battery is already very close to the ideal supercharging temperatures.

The convenience of just plugging your car in and always having it warm and ready to go is pretty unbeatable.

 

[nwdiver]

120 volts, not 110. And here come the cows, moseying on home. I've made no argument for 120v over 240v, that wasn't the point. Use whatever you want, what works for your situation and what is convenient. In truth, it makes no difference for battery life, 120v 16 amps or 240v 48 amps, for example, slow is slow, how patient can you afford to be? I wouldn't go out of my way to use a 120v circuit but if that's what you have and it serves your needs/works in your situation, no worries. There is no disadvantage to the 120v except speed, which as I said is exaggerated at low temperatures. The dogma here is a 240v circuit is a minimum for home charging. I don't disagree with that as a practical matter and for convenience. And if you are installing a circuit, by all means, install a 240v circuit. On the other hand if you need to use a 120v circuit and your circumstance allows, it's just fine.

The point is that the only difference between using ~111v and ~231v is 'L1' (~113v) uses ~10% more energy and takes ~200% longer. Not sure that qualifies as 'fine'; It barely qualifies as 'better than nothing'.

• Slower charging puts the batteries in "charging mode" for far longer and it may be that the charging mode of a battery, especially at incorrect temperatures, harms batteries.

That's not the 'battery' that the electronics that support the battery. Those are 'easy' to swap... at least they were on my car.


There's a whole host of reasons to use ~235v over ~115v. ~None to stick with ~110v unless you have no other option.

 

[Ostrichsak]

120v is just fine for many users. The average commute of 20-30 miles will top off in about 10 hours time on that outlet. Even if you have a longer commute one day with more errands, your battery has enough total range that a couple/few days per week of not being able to recover all of your daily expenditure isn't a big deal.

We've got two Model S (currently with as many as three at a time previously and soon) and we have only one 15A 120v outlet as well as a NEMA 14-50 outlet that I installed. For our minimal needs the 50A outlet is overkill but it's nice to have every now and then when something comes up (usually poor planning or forgetting) and we need to get higher charge quickly.

You could install anything in between those if you wanted but everyone's needs and installation options will differ. Usually anything is possible with the right budget but you can get by with very small (or even no) investments if you're an average user.

Also, don't forget that even a 20A 120v outlet will charge at over 40% faster than a standard 15A 120v outlet to give you an idea on how the smallest of upgrades could actually save you lots of time someday when you may need it.

 

[nwdiver]

120v is just fine for many users.

Unless you live where it can get to <40F where you park your car and the car needs ~900w of the ~1300w L1 can deliver just to keep the battery warm enough to be charged. Not sure I would call being unable to charge my car when it's cold 'fine'. You're also very limited in the ability to precondition the car before leaving in the morning.

You should be using a dedicated 110v outlet for charging anyway. If you're using a dedicated ~110v outlet upgrading it to ~220v costs <$100. I agree you don't 'need' a HPWC or even a NEMA 14-50 but you should be working toward being able to plug in at L2. L1 is not 'fine' for daily use.

 

[Ostrichsak]

Unless you live where it can get to <40F where you park your car and the car needs ~900w of the ~1300w L1 can deliver just to keep the battery warm enough to be charged. Not sure I would call being unable to charge my car when it's cold 'fine'. You're also very limited in the ability to precondition the car before leaving in the morning.

You should be using a dedicated 110v outlet for charging anyway. If you're using a dedicated ~110v outlet upgrading it to ~220v costs <$100. I agree you don't 'need' a HPWC or even a NEMA 14-50 but you should be working toward being able to plug in at L2. L1 is not 'fine' for daily use.

It's been "fine" for me for daily use for years now and I live at 5k ft above sea-level in the Front Range of Northern Colorado. It gets cold here pretty regularly. We go weeks/months where the temp doesn't break 40 degrees Fahrenheit.

Just adding my first-hand experience as a data point and by no means am I saying that what's "fine" for me will be "fine" for everyone but I think we've beaten that horse plenty already.

My opinion is that, after countless first-hand conversations, most people who don't own an EV think you MUST spend thousands of dollars for a charging solution. This is a non-starter for most from what I've found. My goal is to de-stigmatize this portion of EV ownership and I'm first-hand proof that you don't need to spend thousands for a viable EV option. This is especially true for those in warmer climates.

I don't even have 20A 120-volt outlets in my garage either and more and more I'm seeing garages built w/20A circuits. That extra 40%ish charge rate for pennies would be glorious.

Sure, some have unusual electrical circumstances but I still stand behind my statement that for most owners their standard garage wiring will suffice or, at most, minor upgrades can be done on a budget.

 

[eevee-fan]

It's been "fine" for me for daily use for years now and I live at 5k ft above sea-level in the Front Range of Northern Colorado. It gets cold here pretty regularly. We go weeks/months where the temp doesn't break 40 degrees Fahrenheit.

Just adding my first-hand experience as a data point and by no means am I saying that what's "fine" for me will be "fine" for everyone but I think we've beaten that horse plenty already.

My opinion is that, after countless first-hand conversations, most people who don't own an EV think you MUST spend thousands of dollars for a charging solution. This is a non-starter for most from what I've found. My goal is to de-stigmatize this portion of EV ownership and I'm first-hand proof that you don't need to spend thousands for a viable EV option. This is especially for those in warmer climates.

I don't even have 20A 120-volt outlets in my garage either and more and more I'm seeing garages built w/20A circuits.

Sure, some have unusual electrical circumstances but I still stand behind my statement that for most owners their standard garage wiring will suffice or, at most, minor upgrades can be done on a budget.

Agreed, and the whiners who insist you still need to go out DCFC every week will get tired or that and just let the car catch up on charging over the weekend. At home charging is still cheaper than public charging out there, except the free ones, of course.

 

[Cory151]

Technically 110V low amperage charging is the BEST form of charging for long term battery health. That goes for all 18650 Li-ion cells not just Tesla. Low C rate charging is best so long is time is not a factor.

 

[dhanson865]

Unless you live where it can get to <40F where you park your car and the car needs ~900w of the ~1300w L1 can deliver just to keep the battery warm enough to be charged. Not sure I would call being unable to charge my car when it's cold 'fine'. You're also very limited in the ability to precondition the car before leaving in the morning.

You should be using a dedicated 110v outlet for charging anyway. If you're using a dedicated ~110v outlet upgrading it to ~220v costs <$100. I agree you don't 'need' a HPWC or even a NEMA 14-50 but you should be working toward being able to plug in at L2. L1 is not 'fine' for daily use.

you keep saying 110v and 220v and yet you are in the US.

In the US nominal is 120v and 240v and has been since the 1900s.

> In the United States in the 1920s, utilities formed joint-operations to share peak load coverage and backup power. In 1934, with the passage of the Public Utility Holding Company Act (USA), electric utilities were recognized as public goods of importance and were given outlined restrictions and regulatory oversight of their operations.

> In 1942, the Edison Electric Institute published the document Utilization Voltage Standardization Recommendations, EEI Pub. No. J-8. Based on that early document, a joint report was issued in 1949 by the Edison Electric Institute (EEI Pub. No. R6) and the National Electrical Manufacturers Association (NEMA Pub. No. 117). This 1949 publication was subsequently approved as American National Standard EEI-NEMA Preferred Voltage Ratings for AC Systems and Equipment, ANSI C84.1-1954.

I can't say what year your state or local utility switched to 120v/240. But I sure know now that the spec is 120v/240v plus or minus a percentage.

ANSI C84.1 Service Voltage Limits

� Range A minimum voltage is 95% of nominal voltage
� Range A maximum voltage is 105% of nominal voltage

The Canadian standard is CAN3-C235-83 and allows for a slightly wider range of roughly -8%/+4%.

114V is 5% below nominal

110V is over 8% below nominal (apparently OK in Canada, but not in the US).

 

[nwdiver]

you keep saying 110v and 220v and yet you are in the US.

L1 vs L2 that's it.... 110/115/120 (whatever) vs 208/210/240 (whatever)

Technically 110V low amperage charging is the BEST form of charging for long term battery health. That goes for all 18650 Li-ion cells not just Tesla. Low C rate charging is best so long is time is not a factor.

???? Based on what? You're suggesting a battery designed to handle 60kW of regen and >100kW of fast charging is going to notice the difference between 1.3kW and 11kW? It would be a gross exaggeration to call that a rounding error.

MUST spend thousands of dollars for a charging solution.

????

You should be using a dedicated 110v outlet for charging anyway. If you're using a dedicated ~110v outlet upgrading it to ~220v costs <$100. I agree you don't 'need' a HPWC or even a NEMA 14-50 but you should be working toward being able to plug in at L2. L1 is not 'fine' for daily use.

 

[dhanson865]

L1 vs L2 that's it.... 110/115/120 (whatever) vs 208/210/240 (whatever)

So basically Mr. Mom then?

Your prior post that I quoted didn't mention a range, just a single 110v and 220v. I'm saying that hasn't been an accurate label for an outlet in the US for decades so either specify the range or at least switch to the correct numbers.

 

[nwdiver]

I thought you were trying to have a technical conversation.

Yes... without being uselessly pedantic

 

[dhanson865]

Yes... without being uselessly pedantic

https://i.imgur.com/7Jw5E01.jpg
https://i.imgur.com/eLR6p04.jpg

Those two images were from someone in the US that was charging their EV on a voltage lower than nominal. The cause was a substandard wiring/outlet and an EVSE trying to pull the same KW by raising the Amps as the voltage dropped. It's a simple feedback loop, resistance is high, voltage drops, heat increases, resistance increases, voltage drops, and so on. Eventually the heat is enough to start a fire.

Anyone that thinks 110v is normal when 120v is the actual norm might not notice that as an issue and go to bed. Anyone that knows the voltage is well below normal might unplug and have the circuit checked out before they charge.

Correcting that misconception might save someone from burning their house down.

I don't consider that useless or pedantic.

 

[nwdiver]

Anyone that thinks 110v is normal when 120v is the actual norm might not notice that as an issue and go to bed. Anyone that knows the voltage is well below normal might unplug and have the circuit checked out before they charge. Maybe it might save someone from burning their house down.

I don't consider that useless or pedantic.

It's voltage drop not the 'nominal' voltage that's important. I run a solar PV installation company. I've seen unloaded voltage anywhere from 110 to 130. Sometimes a little over 130. Someone thinking 120 is normal when it started at 128 could also have a fire. So ya.... 'uselessly pedantic'

Plus the car monitors the voltage and will reduce the charge rate if voltage dips. If it starts at 108 and voltage drops to 107 it will happily pull 12A. If it starts at 125v and voltage dips to 115v it will probably reduce current to ~8A or so. So ya... 'uselessly pedantic'

 

[dhanson865]

Plus the car monitors the voltage and will reduce the charge rate if voltage dips. If it starts at 108 and voltage drops to 107 it will happily pull 12A. If it starts at 125v and voltage dips to 115v it will probably reduce current to ~8A or so. So ya... 'uselessly pedantic'

Tesla's might be safer in that regard but there are still hundreds of thousands of non Tesla EVs in the US and some people, as shocking as it might be to you, may have one of them in addition to their Tesla. I can tell you with certainty a Nissan Leaf on the stock EVSE won't back off before a fire occurs in the scenario I described.

I consider your attitude towards public education about electrical safety cavalier and condescending. But you do you.

 

[nwdiver]

I consider your attitude towards public education about electrical safety cavalier and condescending. But you do you.

Again.... 'normal' voltage is irrelevant (within the acceptable range +/- 10% of 120v) and varies A LOT. It's voltage DROP the indicates there could be an issue NOT 'normal' voltage. Some places I've seen it's ~110v. It's almost always 110v... that's just what it is. Doesn't mean there's a problem.

 

[dhanson865]

Again.... 'normal' voltage is irrelevant (within the acceptable range +/- 10% of 120v) and varies A LOT. It's voltage DROP the indicates there could be an issue NOT 'normal' voltage. Some places I've seen it's ~110v. It's almost always 110v... that's just what it is. Doesn't mean there's a problem.

ANSI C84.1 Service Voltage Limits are +-5% not 10% so if you think it's OK to just flaunt standards that's you doing you.

 

[nwdiver]

ANSI C84.1 Service Voltage Limits are +-5% not 10% so if you think it's OK to just flaunt standards that's you doing you.

~10% is generally the equipment tolerance. I know my 240v inverters trip at 264v.

Regardless it's voltage drop. That's the point I'm getting at. If your voltage is 108v but you stated at 110v you're ok. If your voltage is 112v but you started at 127 you're probably not ok.

 

[dhanson865]

~10% is generally the equipment tolerance. I know my 240v inverters trip at 264v.

Regardless it's voltage drop. That's the point I'm getting at. If your voltage is 108v but you stated at 110v you're ok. If your voltage is 112v but you started at 127 you're probably not ok.

If your neighborhood is resedintial and should be 120v and you "start" at 110v you already have a voltage drop. At that point safety demands you take a voltage tester and work your way back the chain

* outlet
* wiring
* breaker

and so on until you find either the voltage past the demark or the spot in your internal infrastructure that is the cause of the voltage drop.

If you only check the voltage at one spot and it's not nominal voltage for the part of the world you are in you better start doing your homework or you risk a fire.

And if the voltage past the demark is outside the spec you call the utility and report that so they can service their equipment if needed.

 

[nwdiver]

If your neighborhood is resedintial and should be 120v and you "start" at 110v you already have a voltage drop. At that point safety demands you take a voltage tester and work your way back the chain

Yep... called the utility.... they investigated... said it was fine. Like I said. It can vary A LOT. It's 110/220 at the pole. As long as voltage stays >108/216 everything works fine.

Any 'fire' would be on the utility side since that's where the voltage drop occurs.

 

[dhanson865]

Yep... called the utility.... they investigated... said it was fine. Like I said. It can vary A LOT.

yes but there is a big difference between "I checked all the steps required for safety and talked to my utility" and "oh well it's 110v I'll just start charging and hope nothing catches on fire".

And for the safety of all the people you deal with online and off it'd be prudent to speak the lingo of the actual specs for the region. So they can make the same decisions that you did, an informed decision.