Charging specs updated in Blank Slate description.

[bartflossom]

I am attempting to understand electricity here but I need someone to dumb this down for me. I had calculated that “20% to 80% in 20 hours” would be just enough for me, so I would stick with a regular outlet that looks like ( D= ). I believe the outlet is 15 amps. If I understand you correctly, you’re saying I need at least 16 amps? So my standard outlet won’t be enough?

If that’s the case, very misleading on Slate’s part.

I'm with you Adele. Computing electrical amps/volts/ohms gives me instant "tired-head". I'm glad there are so many capable people in this forum.

 

[Doctors Do Little]

I'm with you Adele. Computing electrical amps/volts/ohms gives me instant "tired-head". I'm glad there are so many capable people in this forum.

We really do have some smart folks lurking around.

 

[tubes]

I had a long series of electric engineering courses in college and although I could do the math, I just watch our esteemed members here take care of it.

Now if someone ever starts talking about field theory and Nyquist plots, I'm going to ignore the thread.

 

[phidauex]

I already have a 20amp 240V line in the garage. The 30amp line just got sacrificed for a cargo lift which only needed 20amp but the electrician kept mis-remembering that the passenger lift needed 30 amps and ran off that one! Can I use the 20 amp 240V line, with a plug converter, to charge the Slate? (They only show 30, 40 and 50 amp receptacles.)

Yes you can use it charge the Slate, but probably not with the provided charger. You'd need a charger that can be set to 16A @ 240V, with a setting on a display, or a dip switch. They do exist, but that isn't terribly common in "standard" EVSEs. The GrizzlE is a good reasonably priced option that can be set to 16A.

The Slate charger might, we don't know yet, but I wouldn't bank on it.

The charge power would be 3.8kW, so a little less than half what you'd get with a full 40A charge, but three times better than a 120V charge. Unless you commute a lot of miles every day, that circuit would be very likely to meet your needs.

 

[SailorDan]

Thanks for the help.

I will also ask my regular electrician how much it would cost to rerun the 20 amp line as 30 amp or higher. It would be nice to have dual outlets, one inside the garage and one outside on the carport.

I am just about out of breaker slots on the board!

 

[phidauex]

Thanks for the help.

I will also ask my regular electrician how much it would cost to rerun the 20 amp line as 30 amp or higher. It would be nice to have dual outlets, one inside the garage and one outside on the carport.

I am just about out of breaker slots on the board!

If they are running new wires, ask about running the circuit as a 100A and putting a subpanel in the garage. Now new outlets are a 30 min job!

 

[Hoosier Daddy]

I have to agree, 68 amps is dead wrong. That means the circuit breaker would need to be rated at 85 amps! (125% continuous current draw). As an example, Tesla on board chargers draw 32 max amps on a recommended 50 amp breaker @ 240 volts.

Just FWIW while some Teslas have double 16 AMP capacity, my Model 3 Performance and maybe all double motor models have triple 16 AMP. My Model 3 Performance charges at 48 AMPS for 41 MPH.

 

[phidauex]

11.5kW, aka 48A at 240V, is a pretty common onboard charger specification (including for the Slate). That typically implies a hardwired EVSE on a 60A breaker.

Even then you might not hit the full charge rate, there will be some voltage drop out to the EVSE so maybe you are actually hitting 11.1kW or something. Splitting hairs really.

 

[kvermeer]

I actually will have to check whether the circuit breaker is 15A or 20A, but good to know that it's easy to change it if needed.

It's easy to change from a 20A, 12 gauge circuit with "undersized" NEMA 5-15R receptacles to a 20A circuit with NEMA 5-20R combo receptacles.

It is not easy to change from a 15A circuit to a 20A circuit.

 

[adele]

It's easy to change from a 20A, 12 gauge circuit with "undersized" NEMA 5-15R receptacles to a 20A circuit with NEMA 5-20R combo receptacles.

It is not easy to change from a 15A circuit to a 20A circuit.

I misread, thanks!

 

[007]

For 16A continuous, you'd need at least a 20A circuit. The receptacle would look like this (with the horizontal slot)

That outlet requires 20 amp wiring from the breaker box. But a regular outlet is also allowed to be wired to 20 amps. So you can be pretty sure the 5-20 is 20 amps but a 5-15 outlet could be either.

 

[danielt1263]

Yes you can use it charge the Slate, but probably not with the provided charger. You'd need a charger that can be set to 16A @ 240V, with a setting on a display, or a dip switch. They do exist, but that isn't terribly common in "standard" EVSEs. The GrizzlE is a good reasonably priced option that can be set to 16A.

The Slate charger might, we don't know yet, but I wouldn't bank on it.

From the FAQ:

"The included Standard Charging Cable works with NEMA 14-30, 14-50 and 14-60 outlets."

 

[007]

From the FAQ:

"The included Standard Charging Cable works with NEMA 14-30, 14-50 and 14-60 outlets."

It looks like there's an adapter included that will allow it to charge in a "normal" 120v outlet.

 

[phidauex]

From the FAQ:

"The included Standard Charging Cable works with NEMA 14-30, 14-50 and 14-60 outlets."

Yes, so by default must support 240V @ 24A and 40A. The 14-60 outlet is uncommon, but not clear if they support 48A charging through this EVSE, or still just 40A, but physically plugged into a 14-60 if that is what you happened to have.

To do 240V 16A charging it would need an adapter to a 6-20 plug, or the ability to use a generic adapter and set the current limit with a switch (not likely).

 

[beatle]

I never really looked at that picture very closely, but it looks like you can plug it into a 14-30, 14-50, or 14-60 by rotating the neutral lug into one of 3 different orientations. As @phidauex said, I'm not sure if it will actually draw 48A - it might only draw 24A, but it allows flexibility in other plug types. This is definitely on brand for Slate, allowing flexibility at a very low cost. The Tesla UMC will draw up to 32A and adjust current draw automatically, but you need to carry $60 adapters to do that. Slate does it at 24A, but with a switch to make it "free." You can put almost 12% back into the battery per hour at 24A (at 90% charging efficiency) and fill up from zero in just under 12 hours.