Problems with 120v charging

[Cosmacelf]

I've been using 120V (please, 110V hasn't been used in north america for 60+ years), for the last year and it has worked fine.

Two things. Charge to the daily trip limit (which is 80% I believe, whatever the bar is on the charge limit screen). That's what Tesla recommends as a no degradation daily charging amount, so no need to go below that.

Second, do you have a 20A breaker on your plug rather than a 15A breaker? If so, you can use the Tesla NEMA 5-20 adapter to charge from a 120V outlet and get about 42% faster charging. It is more efficient, wastes less electricity.

Did you buy a new 100D or a used one?

 

[Nilnoc]

Two things. Charge to the daily trip limit (which is 80% I believe, whatever the bar is on the charge limit screen). That's what Tesla recommends as a no degradation daily charging amount, so no need to go below that.

Second, do you have a 20A breaker on your plug rather than a 15A breaker? If so, you can use the Tesla NEMA 5-20 adapter to charge from a 120V outlet and get about 42% faster charging. It is more efficient, wastes less electricity.

Did you buy a new 100D or a used one?

I've delved into the several discussions on the 'absolute best level to charge to.' Honestly, the weight of opinion is on 80 to 90%. And if I were driving the car on a commute every day that's what I'd be doing. But as I said in the original post, the car will be mostly a garage queen. For absolute battery longevity, many have said that keeping the car at around 50% SOC is best. I dunno. It is clear that you don't want to let the car sit at a 100% SOC. I'll keep an open mind and dial in a daily charge level that will work for me.

I did check to see if the breaker for the garage outlet is 15A or 20A. Sadly, it is 15A.

I have a Tesla-approved electrician coming on Friday to give me an estimate on putting a real charger in my garage. If the estimate is horrendous as anticipated, I might ask him whether the actual wire already in place would support upgrading to a 20A circuit.

I put in my order on Dec. 29 for a new MX 100D – due for delivery next month. I posted my charging question on the Model S forum because that's where the expertise is.

 

[gregd]

I did check to see if the breaker for the garage outlet is 15A or 20A. Sadly, it is 15A.

So there is only the one circuit for the whole garage? Normally a detached garage has a separate panel, with a couple of breakers to feed the lights and plugs. That panel would be fed from the house main panel with (again, usually) a double breaker. That's the important one to determine what you can do to the garage without digging up the yard.

 

[f-stop]

I did check to see if the breaker for the garage outlet is 15A or 20A. Sadly, it is 15A.

I have a Tesla-approved electrician coming on Friday to give me an estimate on putting a real charger in my garage. If the estimate is horrendous as anticipated, I might ask him whether the actual wire already in place would support upgrading to a 20A circuit.

You'll need 12 gauge wiring for a 20A circuit (usually yellow Romex), whereas a 15A circuit has 14 gauge (white).

One other thing to remember if it turns out you can get 120V 20A in your garage: Remember to buy the optional NEMA 5-20 adapter since the UMC kit provided with the car doesn’t include one - it only comes with 14-50 and 5-15 adapters. Even if you plug into a 20A circuit with the 5-15 adapter, you'll only charge at 12A (80% of the rated 15A of the adapter)

 

[GSP]

@Nilnoc,

Lots of good advice already in this thread.

When working with your electrican make sure to show him the HPWC manual page that shows that it can be configured for any circuit, from 15 A to 20 or 30 A all the way to 100 A. Many electricians just provide a quote for a 100 A circuit which can be thousands of dollars. Ask him what the max voltage and current your existing wire to the garage can support.

As has been mentioned, if you don't want to buy the HPWC for $500, Tesla sells inexpensive 20 or 30 A adapters for the UMC that comes with the car.

If you do end up using an existing 120 V outlet for your daily charging, I strongly recommend replacing the "$1.09 contractor special" outlet with a better grade, such as a commercial or industrial grade 120 V outlet. They are available for the extravagant sum of $3-4. Also, be sure to use the screw terminals to attach the wires, not the "push in" connections. The latter only have a small point of contact with the wire and are not suitable for continuous 12 A loads.

GSP

PS. Here is an industrial grade outlet for under $9. I am pretty sure I have seen them for less, but this is the best I found with just a short search:

https://www.amazon.com/Leviton-5242...&keywords=Leviton+5-15+wall+outlet+industrial