Charging Nema 6-20?

[MikeR55]

I am renting a house, and have been plugging in my Tesla and getting 5 miles per hour. And then I realized that looks like I can do a 6-20 based on the input of the plug.

This is an outdoor plug that the sprinkler system is plugged into.

Is that correct? Is there anything else I need to know about the receptacle? Like I said I'm renting so I really don't know much about it, should I just go buy a adapter. Hope that works and gets me more than the normal charging I'm doing right now?

 

[huangm777]

That is not a NEMA 6-20. A NEMA 6-20 looks like this:

Note the horizontal prong on the right. This is my own plug; it's what I use to charge my Tesla.

What you're looking at is a NEMA 5-20, which is backwards compatible with the standard household NEMA 5-15. It's 120V like a standard plug, though it's very slightly faster since it carries 20A. You'll get about 6 miles per hour of charge as opposed to 3-5 miles. It's not anywhere what you can get for a 240V plug unfortunately.

See this table for more info.

 

[MikeR55]

That is not a NEMA 6-20. A NEMA 6-20 looks like this:
View attachment 502173
Note the horizontal prong on the right. This is my own plug; it's what I use to charge my Tesla.

What you're looking at is a NEMA 5-20, which is backwards compatible with the standard household NEMA 5-15. It's 120V like a standard plug, though it's very slightly faster since it carries 20A. You'll get about 6 miles per hour of charge as opposed to 3-5 miles. It's not anywhere what you can get for a 240V plug unfortunately.

See this table for more info.

Oh ok- so that would not get me more charging then?

 

[vickh]

Oh ok- so that would not get me more charging then?

little more

 

[joelliot]

Oh ok- so that would not get me more charging then?

As mentioned, it would be 1-2 mph faster, so over the course of 10-12 hour overnight it might be worth it. I purchased a Tesla 5-20, because one of the places I visit has a 20 A outlet. When I actually used it, the voltage would drop and I would end up only getting around 12 A, so just because the outlet is 20 A, there is not guarantee that it will work at 20 A. Given that it is a shared outlet with a sprinkler, you may be in a similar situation. Having said that, it's only $35 for the Tesla cord and it's something I keep in the car because many commercial outdoor outlets seems to be 20 A in my area.

 

[jrcase]

On a 5-20, I get 7 mph. On a 5-15, I get 4-5 mph.

 

[ralph142]

Check to see if anything else is running on the circuit, freezer, garage opener, etc. Very common in garages and outside for lights etc. If you were pulling 12 amps out of it a switch up to 16 amps, you may overload the circuit

 

[MikeR55]

as far as I know nothing else is. But thanks I'll keep an eye on that. Right now, 12a and getting 6miles an hour 116v

 

[Tz00]

You also might want to check the size of the breaker feeding that circuit. Sometimes a 20A GFCI outlet is installed, but the breaker is only 15A and the wire size is only rated for the 15A breaker.

 

[rdskill]

I use the 5-20 at work everyday.

I was using the regular for a while, but only got a charge rate of 1kw. With the 5-20 adapter I now get 2kw when charging. This adds about 25% after 8 hours of charging. So start with 40% and end with 60% for the drive home then back to work (20 miles each way with 3/4 on the interstate. Sometimes bumper to bumper. Sometimes flying.).

This gives me a small gain everyday and then on the weekends I sometimes have to SC as I can't charge at home.

 

[MikeR55]

Bought the NEMA 5-20- the difference between that and the regular plug:

NEMA 5-20: 16A - 6 to 7 miles an hour
Regular: 12A - 5 to 6 miles an hour

Worth $35? Maybe...?

 

[DaveRZ]

The simple math is that a 5-20 will give you 33% more power than a 5-15. That's a fair jump in power if you must charge from 120v.

Using MPH or Kw displays to compare isn't very helpful since there's so much rounding of numbers going on. Charging from a 5-15 will have the car reporting 1 Kw because 1440 watts rounds down to 1Kw. The 1920 watts you'll get from a 5-20 will round up to 2Kw

 

[rdskill]

The 5-20 (Charges at 16A) is also more efficient than the 5-15 (Charges at 12A) when it comes to amps that make it into the battery (this is why Telsa is switching to charging for amps used vs amps into the battery). I was seeing appox 27%-25% loss and appox 18% to 16% loss on the 5-20.

If its a warm or hot day, the 5-20 will drop to 12A of charge and the 5-15 will drop to 8A.

 

[MikeR55]

So 5-20 should save me money?

 

[DaveRZ]

So 5-20 should save me money?

Yes, but a VERY small amount.

There's a certain amount of energy needed to run the charger itself and all the various computers/electronics that monitor the charge, communicate with your phone, etc... the faster you charge, the shorter amount of time all these things need to be powered up instead of sleeping. This is why it would be more efficient to charge faster.

I have no idea how much energy is used by the electronics, but lets just say its equivalent to running your high-powered laptop PC at home. Lets say you run your laptop 6 hours a day normally. Something in your life changes and you now only use your laptop 4 hours a day. Yes, you will save money. Enough to even notice on your electric bill? Probably not, unless you're really paying attention.

Having the ability to charge faster has more benefit to those that have Time-of-use billing from their power company. This way you can charge during "off peak" hours and get a cheaper rate. You need the faster charging to make sure you complete your charge during the off peak time window.

 

[MikeR55]

Yeah, I do have time-of-use from 8 p.m. To 10 a.m. Is the cheapest so that's the only time I charge.

 

[xxxotic]

Just noticed that I have outlets in my ceiling for garage door openers and that they are 6-20. Always thought it was a 5-20 plug.
Since only one of the garage doors has an opener, I could have avoided putting in the 240 volt outlet and charged at about 15 mph instead of 30, which would have met my needs.

Just figured I would pass this on, since when I visit friends I usually just plug into a wall outlet and get about 3 mph. If you unplug the garage door plug and it has a 6-20 outlet and you get the adapter, you can charge a lot faster.

 

[DaveRZ]

Just noticed that I have outlets in my ceiling for garage door openers and that they are 6-20. Always thought it was a 5-20 plug.
Since only one of the garage doors has an opener, I could have avoided putting in the 240 volt outlet and charged at about 15 mph instead of 30, which would have met my needs.

Are you sure about that? I've never heard of a 240v household garage door opener.

I would think your garage likely has 5-20 outlets when you would've expected to see 5-15 outlets.

 

[Outpost53]

It's probably a single 5-20 instead of a duplex.