TYPE 2 CHARGER SPEEDS

[MOE J]

All I ever seem to get is 6 - 7 kW from type 2 public chargers , they are free but is that the standard range. Also what’s the + digit kWh

 

[E90alex]

How fast you charge depends on the charger. Most public chargers are about that speed.

The +_kWh is how much was added since you started charging.

 

[Cosmacelf]

Yes, that's common for public level 2 chargers. The +1 kWh says you've added 1 kWh of charge to your vehicle since the session start.

 

[dsm363]

All I ever seem to get is 6 - 7 kW from type 2 public chargers , they are free but is that the standard range. Also what’s the + digit kWh

That would be about the most power you can expect from most level 2 chargers on modern Teslas. The + kWh is the number of kWh you've added during that charging session. So here, you added 1 kWh so far.

 

[SourJellybeans]

OP may already know this, but to spell it out for others who may come across it:

kW = rate
kWh = capacity

kWh is literally the rate * amount of time. If you charge at a 7kW rate for 1 hour, that’s 7kWh. If you charge for 2 hours, that’s 14kWh. If you charge for only 0.5 hours, that’s 3.5kWh.

You can calculate the rate, kW, from the Amps * Volts. In your photo, you’re getting 30A at 234V, which 30*234 = 7,020Wh = 7.02kWh.

If you have a post-2021 Model 3 LR with an 82kWh max capacity battery, and you’re currently at 46%, 0.46*82 = 37.7, you’re currently at 37.7kWh. If you want to charge to 100%, then you need to add 44.3kWh. At a rate of 7.02kW, that will take 44.3kWh/7.02kW = 6.31h.

I believe the absolute max possible a J1772 connector can deliver is 80A at 240V, or 19.2kW. If you were at such a charger, you could theoretically finish charging in 2.31h instead. However, I’m not sure how prevalent those are, as it requires a 100A circuit (the best practice is to operate at 80% of the circuit value), and I’m sure many places would rather install 2x chargers instead of one and potentially serve twice as many people.

Level 2 charges work best for places where you’ll be there several hours - like a hotel, theme park, museum, etc. Level 3 DC fast chargers work better for where you’ll only be stopping in briefly - restaurants, freeway rest stops, grocery stores. Level 1 chargers work best at home (any standard 120V 15A outlet with your mobile charger) where you can take a day or two to charge up to full, though some people install Level 2 chargers at home if they drive a lot (>40-50 miles per day) or have more than 1 EV.

Note all calculations are idealized and don’t consider losses or inefficiencies, but for back-of-napkin they’re good enough.

 

[MOE J]

Thank u that clears things up

 

[cpa]

kW = rate
kWh = capacity

You can calculate the rate, kW, from the Amps * Volts. In your photo, you’re getting 30A at 234V, which 30*234 = 7,020Wh = 7.02kWh.

Beans, you contradicted yourself. Your first statement is correct. You should have dropped the "h" from the second as you are referring to rate. Hence, the product is 7,020 watts, or 7.02 kilowatts.

On the subject of the onboard chargers in Tesla vehicles, Tesla has dicked around with the chargers over the years. When we bought our S in '14, they came standard with a 40A charger. They offered an option to add a second 40A charger. We availed ourselves of this option. I have charged at anywhere from 48A up to the full 80A over the years at various destinations. Tesla discontinued this second 40A charger a few years later.

When we bought the M3 Long Range, it came standard with a 48A onboard charger. I think my son's '23 MY also has a 48A charger. But I recall that there have been some models that have 32A. There very well could be other models with other sizes too.

 

[cwerdna]

In the US, a lot of public L2 charging is only 30 amps max and 208 volts is common (common voltage for commercial settings). 208 volts * 30 amps = 6240 watts = 6.24 kW

If you find 240 volts * 30 amps = 7200 watts = 7.2 kW.

CT4000: 30A Dual Port Level 2 EV Charger | ChargePoint is super common and only 30 amps max. We have dozens at my work and it's 208 volts there. I've occasionally found 240 volt public L2, including on CT4000.

And yes, 234 volts * 30 amps = 7020 watts = 7.02 kW. So yes, if you charge at 7.02 kW * 1 hour --> 7.02 kWh came out of the "wall". 7.02 kW * 2 hours --> 14.04 kWh out of the wall. I'm not surprised about the slight voltage drop/variance.

The onboard charger was mentioned earlier. OP can look at the top of 3 Factors that Determine Electric Car Charging Times. For the US and presumably Canada too. Tesla stopped shipping anything in those markets with above a 48 amp OBC. See https://www.tesla.com/support/charging/onboard-charger. So, if you find any L2 EVSE advertising via pilot signal duty cycle (Basics of SAE J1772) that it can output >48 amps, it won't help those cars. 48 amps is as much as those cars will pull over J1772.

240 volts * 48 amps = 11,520 watts = 11.52 kW.

For Models post-Roadster (I can't speak to Cybertruck or Semi), Tesla has had these OBC max total amperages in the US: 32, 40, 48, 72 and 80.

 

[MOE J]

Are these chargers affected by extreme cold temps, are they any faster in the summer ?

 

[E90alex]

No

 

[dsm363]

No

If you are charging on a 120V outlet and it's 30 below zero with a cold battery, charging speed would be impacted, wouldn't it?

 

[MOE J]

Type 2 public chargers I think the J1772 adapters suck up some of the efficiency

 

[E90alex]

If you are charging on a 120V outlet and it's 30 below zero with a cold battery, charging speed would be impacted, wouldn't it?

Sort of. The charging speed isn’t necessarily impacted but the battery might need some time to warm before it accepts a charge. But when have you ever seen a level 1 public charger? Also being a public charger, one would assume the battery would be warm enough to charge since you had to drive to it.

 

[Cosmacelf]

If you are charging on a 120V outlet and it's 30 below zero with a cold battery, charging speed would be impacted, wouldn't it?

Yes it would. I would never advise to rely on 120V/15A charging in the winter as a regular thing (do it, of course if you have low charge and you have no other choice). The original question was whether a Level 2 charger would be impacted, and the answer is that it would take a small hit, not very noticeable.

Basically, the battery needs to be warm to accept a charge, so some amount of power will be diverted to warming the battery in cold weather.

120V charging is generally not recommended since it costs more over time. There's a calculator at the bottom of this page: Advice for EV Charging in North America

 

[dsm363]

Sort of. The charging speed isn’t necessarily impacted but the battery might need some time to warm before it accepts a charge. But when have you ever seen a level 1 public charger? Also being a public charger, one would assume the battery would be warm enough to charge since you had to drive to it.

I had to use a 120V outlet at home for a few weeks when I moved once and it was around freezing. The battery was so cold I think I gained 5 miles of range overnight. But you're right, there are basically no public level one chargers but there can be a bed and breakfast/hotel and things now and then where they allow you to plug into an outlet.

 

[cwerdna]

Sort of. The charging speed isn’t necessarily impacted but the battery might need some time to warm before it accepts a charge. But when have you ever seen a level 1 public charger? Also being a public charger, one would assume the battery would be warm enough to charge since you had to drive to it.

I've never personally seen a public L1 EVSE. For ages, Products | PowerPost EVSE only sold an L1 unit but I've never seen one in the wild.

Then again, I don't really go out of my way to look either.

 

[SourJellybeans]

Beans, you contradicted yourself. Your first statement is correct. You should have dropped the "h" from the second as you are referring to rate. Hence, the product is 7,020 watts, or 7.02 kilowatts.

Gah, you're correct, a typo, and seems I can't go back and edit that post now...