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Charging Rate at 120v (Nema 5-15) is better than advertised

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So I don't know if anyone else is experiencing this but I am finding that I a getting a charging rate of 4 mph using a standard 120V plug.

I have tested this a few times now with and without using a 50ft extension chord off of several outlets in my house. For example I charged last night for from 6:30pm to 7am this morning (12 1/2 hours) and added 50 miles of rated range (started at 159 rated and ended at 209 rated). The display read a consitent 12 amps and between 114 and 115 volts)

The Tesla site says this setup should charge at 3 mph.

This is a big deal for me for my summer vacation in Maine where I only have access to 120 volt outlet. Gaining 40 to 50 miles overnight versus 24 to 26 means that I will be able to gain more miles than I normally consume on a given day on vacation
 
Yes, on a "good" circuit I typically get closer to 4mph on a NEMA 5-15. If there's more of a voltage drop it'll be closer to 3mph.

You can do even better (5mph) if your 120V outlet is on a 20A circuit, with Tesla's NEMA 5-20 adapter ($45).
 
So I don't know if anyone else is experiencing this but I am finding that I a getting a charging rate of 4 mph using a standard 120V plug.

I have tested this a few times now with and without using a 50ft extension chord off of several outlets in my house. For example I charged last night for from 6:30pm to 7am this morning (12 1/2 hours) and added 50 miles of rated range (started at 159 rated and ended at 209 rated). The display read a consitent 12 amps and between 114 and 115 volts)

The Tesla site says this setup should charge at 3 mph.

This is a big deal for me for my summer vacation in Maine where I only have access to 120 volt outlet. Gaining 40 to 50 miles overnight versus 24 to 26 means that I will be able to gain more miles than I normally consume on a given day on vacation


Nice charge rate!

btw if you do decide to to use an extension cord (which isn't recommend by most) make sure you use something that's beefy, something like this Coleman Cable 02688 10/3 Vinyl Outdoor Extension Cord with Lighted End, 50-Feet - - Amazon.com
 
So I don't know if anyone else is experiencing this but I am finding that I a getting a charging rate of 4 mph using a standard 120V plug.

I have tested this a few times now with and without using a 50ft extension chord off of several outlets in my house. For example I charged last night for from 6:30pm to 7am this morning (12 1/2 hours) and added 50 miles of rated range (started at 159 rated and ended at 209 rated). The display read a consistent 12 amps and between 114 and 115 volts)

The Tesla site says this setup should charge at 3 mph.

This is a big deal for me for my summer vacation in Maine where I only have access to 120 volt outlet. Gaining 40 to 50 miles overnight versus 24 to 26 means that I will be able to gain more miles than I normally consume on a given day on vacation

well your numbers aren't integer 4 vs integer 3.

4/3 * 24 = 32
4/3 * 26 = 34.67

How accurate was the 24 to 26 number vs how accurate was the 40 to 50 number?
 
Another option is to get a Quick220 (quick220.com) to combine 2x 110V outlets into a 220V outlet.

You'll still only get 12A, but it will be at 220V instead of 110V, so you will be able to charge at double the rate.


That's assuming your vacation house runs outlets on 2 circuits, but that's almost always the case.
 
yeah it really depends on the voltage the plug provides, i get 6km/hr instead of 5km/hr on 12A, There is a really good plug near home depot (right beside the transformer) that allows me to draw 16A and i still get 119V

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There is a HUGE difference when using a 10-30/14-30 dryer outlet (240v or 7.2kW max) and 5-15 (120v or 1.4kW max).

I'd recommend you make or buy adapters to get you to L6-30 then from there you can get a heavy-duty extension; such as this 50' one: Amazon.com : Conntek RUL630PR-050 50-Feet 10/3 30-Amp 250-volt L6-30 Anti-Weather, Oils, Acids and Chemicals Rubber Locking Extension Cord : Patio, Lawn Garden

You can then buy adapters to go from L6-30 to whatever you need:
10-30: 10-30 to L6-30 Adapter - For charging on most dryer outlets [A10330] - $29.95 : EVSE Upgrade, Low-Cost EV Charging Solutions
14-30: 14 Universal L6-30 Adapter - For 14-30, 14-50, and 14-60 outlets [A14X30] - $37.95 : EVSE Upgrade, Low-Cost EV Charging Solutions (also works on 14-50 and 14-60 with caution)


And if you must still only run at 120v, you'll at least maybe be able to pull 16A (1.9kW) with one of these adapters: 5-15 to L6-30 Adapter - For charging on standard 120V outlets [A15L30] - $25.00 : EVSE Upgrade, Low-Cost EV Charging Solutions

If you can make your own adapters, here's a someone that did just that and has the costs shown: Charger Adapters

For me, I made my own L6-30 adapter from an old Tesla 14-50 adapter I had, then used the high-quality molded adapters (linked above). The molded adapters, if of high-quality use welded connections internally which are vastly superior to the screw-terminal DIY ones. This means there is less voltage drop and heat produced, so more power makes it to the UMC and you charge faster.

Though not recommended for over 24A continuous when using this set-up, with caution I've been able to use it up to 40A. There is appreciable voltage drop, and thus heat, so if carefully monitored it provides a quick charging rate. 30A is more reasonable and within the official NEC rating for the 10-3 SOOW/SJOOW cable I use. Most dryer outlets are within reach with this setup and can get over 40 miles per hour of charge. (over 75' of cable in total) If you are forced to use Tesla's 5-15 adapter, regardless of outlet or extension, the most you can get is about 3-4 miles per hour. If you use my above setup, on 120V, sometimes you can get up to 8MPH. (need to monitor the outlet for heat though!)
 
It's true that, in my experienc,e "regular" people have no idea what kind of outlet their dryer is connected to. But you do, so just go check it out :) If you want to be ready before visiting for the first time, you could ask them to snap a picture.

I've found the biggest problems with residential destination charging is the location of the outlet and the imposition factor of having to ask. If you are armed with a few common adapters and/or extension cords, you should be set. I actually find it quite fun to plan out my charging strategy when visiting family. Researching connectors, cables, it's kinda like a trip to the hardware store. I don't love feeling like I'm being annoying poking around in their laundry room, even if they are totally cool about it.
 
The biggest issue with extension cords is not the conductor size (always use 12 or 10 AWG) but rather the plug. I use 120V 5-15 charging at a local car show every year, and while I have some really decent 12 AWG extension cords, after a couple of hours the cheap plugs on them are very, very hot - almost melting the plastic. I chopped them off and installed new high-quality plugs.

For this reason, I generally point people to #10 AWG contractors' cords that have higher-quality plugs.
 
Ing

i am a big fan of;


a) EVSEupgrade products
b) L6-30 locking extension cords
c) Quickchargepower's 50' UMC
d) Scrounging around to secure ALL UMC adapters including the discontinued 6-50 and 14-30


I am not one of the "electrical police" on this forum nor do i blindly follow every regulatory body, manufactures guidelines, specifications, laws, etc. My life, my rules..... *If* I want to irresponsibly ride my ZRX1200R down rt. 199 on one wheel, I have to accept that I would be breaking the law and accept ALL consequences that come my way. So being the hypocrite that I am,:cool: I vehemently disagree with 95% of everything stated in your below paragraph and I would don my Kevlar underwear immediately 'cause I suspect you are *in* for an A.. chewin' by others.
:eek:



Though not recommended for over 24A continuous when using this set-up, with caution I've been able to use it up to 40A. There is appreciable voltage drop, and thus heat, so if carefully monitored it provides a quick charging rate. 30A is more reasonable and within the official NEC rating for the 10-3 SOOW/SJOOW cable I use. Most dryer outlets are within reach with this setup and can get over 40 miles per hour of charge. (over 75' of cable in total) If you are forced to use Tesla's 5-15 adapter, regardless of outlet or extension, the most you can get is about 3-4 miles per hour. If you use my above setup, on 120V, sometimes you can get up to 8MPH. (need to monitor the outlet for heat though!)
 
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That's why I made the "though not recommended" disclaimer. I am an Electrical Engineer and I know full well the failure modes and the reason for the NEC's 125% rule for continuous loads. A person can be smart, but "people" are dumb.

The NEC is supported mainly by the NFPA which is made up mainly of fire insurance underwriters. Their goal is to reduce claims.

UL in fact began the same way. Underwriter's Laboratories.

Yes, most 5-15's in houses these days seem to be the cheap Chinese-made outlets and are often wired by the rear spring locks, and have appreciable resistance. The sockets wear our form surprisingly few insertion/removal cycles and are definitely not made for daily use. They almost always will overheat when subjected to a 12A contentious load, so using a UMC on on of these is asking for trouble if you don't monitor it.

A Dryer outlet on the other hand is usually only had a few cycles, it's got large fat blades and as long as there isn't aluminum wiring behind it and the screws are tight, they seem to do ok with a continuous load.
 

Thanks. I'll give that a look.

I wanted to have two set of extension cables handle when travel. One for the NEMA 5-15 connection and another for the NEMA 10-30. With those two I can at least cover 95+% of scenario when visiting people houses and not having a super charger within 10 miles around me.

Public charging suck as BLINK and CHARGEPOINT is great if you are at a mall. But if you go to a friend's or relative's place for an all day party, stopping by one of those ain't very practical. Lol!

Like going from LA to San Diego. I'll stop at the Super Charger @ Qualcomm, but will be driving around San Diego and would need to charge while hanging out at a Friend's place.
 
when visiting people houses and not having a super charger within 10 miles around me

Is that even possible in the state of CA?? :biggrin::biggrin:

I always attempt to locate a 5-20 duplex near the load center or a single use one where it is the sole receptacle on a branch circuit such as a washing machine or microwave. Its always good to monitor connection temps as Ing does during the charge cycle.