GFCI for 220v garage receptacle.

[wwhitney]

The ideal situation would be if I could just tell the car what time I want charging to finish, and it charges at the lowest rate that reaches the specified level on time. AFAIK, no manufacturer offers this feature.

That's not ideal by every measure, as usually the car has some fixed electrical overhead while it is running its charger, such as fixed rate coolant pumps, fans, etc. So the overall charging efficiency is higher at higher charge rates.

Of course, the charging system could be designed so that the thermal management runs more intelligently, then the load from it would scale down with the lower charging rate (and could scale down faster than linearly, so you'd save energy there by charging more slowly). If the only other overhead is control electronics, I would think that could be made pretty low. I guess I'm assuming the efficiency of the rectification is constant.

Cheers, Wayne

 

[Fred B]

Those are EVSEs, not chargers. And the 48A ones don’t come with a 14-50P.

The charger is in the car and it controls the charge rate up to what the EVSE tells it is available.

You should review how the J1772 standard works. A user cannot make a car charge at a rate exceeding the hardware in the car.

Quote from one Amazon model:
"The Emporia EV Charging Station is a Level 2 electric vehicle charger that charges any EV up to 40 amps with 22" NEMA 14-50P or up to 48 amps with hardwired installation. It comes with a 24’ cable with an SAE J1772 connector so it works with all electric cars. Its watertight NEMA Type 4 enclosure is made to withstand the elements outdoors."

Set up commissioning procedure is in an app that simply asks if this unit is hard wired or plug in.
Had customer with this. He had total control over Rated Amp (no installer control) on set up it simply asked is it hard wired or plug in. HO actually suggested that it be wired at the lower rating to save money and he would just change the setting to "hard wired" to take advantage of the higher speed. Of course told him no and hard wired to 60A/48A capacity.
Everyone I've dealt with requires a WIFI connection. This Emporia will stay defaulted to the last setting with loss of WIFI. Charge Point and Enphase Default to lowest setting 16A with the loss of WIFI.

A user cannot make a car charge at a rate exceeding the hardware in the car.

Will partially disagree. Can make it to exceed the wiring. This charger (EVSE) will charge up to the capacity inputted into the App. Experimented with it. Time for charge of vehicle changed based on inputted Amperage. 32A was 8hr, 40A was 5-6hr, 48A dropped to almost 3 and a half hour. Charger was put onto a Toyota Highlander PHEV.

Meeting with a Stellantis' Corp EV trainer rep. Speaking on their Specs and requirements. They actually have a requirement that owners limit use of the road side level 3 80A rapid chargers as it would cause plaquing issue within the Battery cell with repeated continuous use of the level 3 charger. Acknowledged the development of even higher level 2 chargers would be similarly detrimental to the vehicle batteries.

The basic is that the battery via onboard system will accept a high rate of charge for the first 80% of battery capacity then internally will throttle back the charge until full charge is achieved.

 

[nietzj]

Curious, I plan to install this EV charger using #6 THHN inside a raceway so I’m good up to 65 amps on the wire and could install a 60 amp breaker. The charger can draw up to 48 amps continuously for hours, the main is 125a. I’m not really comfortable with those numbers even though I understand you can manually dial the charge rate to lower the amp draw to a much lower amperage. Knowing this is for my daughter and unsure is she would lower the setting when charging would it be wise to install a 50a breaker and make sure she charges at no more than 40a or the breaker will trip? Even a 30 amp charge over night would give you 250 miles of range. I think this powerful of a home charging unit is a bit extreme.

 

[retirede]

Curious, I plan to install this EV charger using #6 THHN inside a raceway so I’m good up to 65 amps on the wire and could install a 60 amp breaker. The charger can draw up to 48 amps continuously for hours, the main is 125a. I’m not really comfortable with those numbers even though I understand you can manually dial the charge rate to lower the amp draw to a much lower amperage. Knowing this is for my daughter and unsure is she would lower the setting when charging would it be wise to install a 50a breaker and make sure she charges at no more than 40a or the breaker will trip? Even a 30 amp charge over night would give you 250 miles of range. I think this powerful of a home charging unit is a bit extreme.

If this is a Tesla Wall Connector, you tell it the breaker size during the commissioning process when you first turn it on. The max output is then limited to 80% of the entered breaker size. From that point, the user cannot exceed this value (they can choose to charge slower, though). In your case, you can tell it you have a 40A breaker even though you installed a 50 and charging will be limited to 32A.

 

[nietzj]

If this is a Tesla Wall Connector, you tell it the breaker size during the commissioning process when you first turn it on. The max output is then limited to 80% of the entered breaker size. From that point, the user cannot exceed this value (they can choose to charge slower, though). In your case, you can tell it you have a 40A breaker even though you installed a 50 and charging will be limited to 32A.

Yes this would be the Tesla charger for a Model 3. Thank you, this is a perfect solution. I assume you go always go back and change the breaker size info if necessary. In this case I would probably just use a 60 amp breaker for full flexability.

 

[retirede]

Yes this would be the Tesla charger for a Model 3. Thank you, this is a perfect solution. I assume you go always go back and change the breaker size info if necessary. In this case I would probably just use a 60 amp breaker for full flexability.

You can reinitialize and run the commissioning setup again to change the breaker size setting. But the key thing is that the end-user can’t do this from their Tesla app.

 

[Fred B]

If this is a Tesla Wall Connector, you tell it the breaker size during the commissioning process

Same with Enphase and Charge Point. But issue is with the Cheap Amazon advertised ones, HO has control of the process, not the electrician.

 

[BurnabyBeej]

Dang, you are correct sir. I think I’m going back to plan A for now, 120v 20amp GFCI Receptacle and an occasional stop at the nearby super charging station….done

You are going to burn a lot of power to charge your car up with 120VAC. The efficiency drops off quite a bit when using such a small amount of power. I have a 2017 S75D and it would take well over a day to charge my car with just a wall outlet, albeit a 15A 120VAC one. For the sake of convenience, I would really recommend the 240V option.

 

[letgomywago]

You are going to burn a lot of power to charge your car up with 120VAC. The efficiency drops off quite a bit when using such a small amount of power. I have a 2017 S75D and it would take well over a day to charge my car with just a wall outlet, albeit a 15A 120VAC one. For the sake of convenience, I would really recommend the 240V option.

120v burns more than 240?
Takes longer but watts are watts unless the peticular charger uses a large amount of power to run its electronic controls.

 

[wwhitney]

120v burns more than 240?
Takes longer but watts are watts unless the peticular charger uses a large amount of power to run its electronic controls.

There's often a significant more or less fixed overhead of running coolant pumps, fans, etc.

Cheers, Wayne

 

[letgomywago]

There's often a significant more or less fixed overhead of running coolant pumps, fans, etc.

Cheers, Wayne

How much cooling goes on in the car when it's only trickle charging off a 15 amp outlet.

 

[retirede]

How much cooling goes on in the car when it's only trickle charging off a 15 amp outlet.

None. But there are fixed loads that definitely reduce the efficiency of slow charging. Based on first hand experience, I see 10 to 10.5 KW going into the battery with 11.2 KW on the AC input. At 1.4 KW AC in, I see 1 to 1.1 net to the battery.

300 watts of overhead is insignificant when charging at 10KW. It’s very significant at 1KW.

 

[tortuga]

Same with Enphase and Charge Point. But issue is with the Cheap Amazon advertised ones, HO has control of the process, not the electrician.

and that is the age old electrician problem we can lead them to water but we cant make them drink.
I can't count the number of service calls I have ran back in the day when people put 100 or 150 watt bulbs in a 60W socket and burned up old NM cable.
Or the old screw in fuses where you could screw in a 30A if your 15 blew.
Or replacing a 15A breaker with a 30A.
We got to do our best to educate the customer, manufacturers come up with solution's but there is only so much you can do.

What we can do as an industry is get to the bottom of these claims that 50A Leviton receptacles are melting down when carrying normal current and properly installed (40 amps continuously).
That is a very serious claim that could affect much more than EV's
If any members on here encounter any of these melted receptacles please make a thread about it, document what you find as to charger settings and make a incident report with UL and send the receptacle to UL and involve your local AHJ.

 

[retirede]

That is a very serious claim that could affect much more than EV's

Except I can’t think of any load other than EV charging that will draw 40A continuously (>3 hours) from a 14-50.

 

[tortuga]

Except I can’t think of any load other than EV charging that will draw 40A continuously (>3 hours) from a 14-50.

Yeah an EV would be the most common.
I can think of a few that could be close but they would not be as continuous as the charger.
A temp power 'spider box' at an event, powering stage lights.
A food truck with a large load, I have seen them trip a breaker.
A pottery kiln using that configuration would be close, but the elements cycle on and off.
A generator.
Large RV running AC on a hot day.

 

[tom baker]

FYI 220 is not a standard voltage. See the first post in this topic

 

[brycenesbitt]

The ideal situation would be if I could just tell the car what time I want charging to finish, and it charges at the lowest rate that reaches the specified level on time. AFAIK, no manufacturer offers this feature.

+1 on that. Curiously, all Android phones have this feature. It's called adaptive charging, and you enable it by setting an alarm clock. It charges at the rate needed to be at 100% by the alarm time (or add a "chargie" to set the target to 80%).

 

[brycenesbitt]

If I install a nema 14/50 220 volt receptacle in a garage specifically to charge a Tesla does the receptacle need a GFCI 2-pole breaker?

Tesla says no for the hardwired units. Only the basic Tesla charger has a plug.

 

[wwhitney]

Tesla says no

Yet the 2020 NEC (625.54), or the 2017 NEC if your jurisdiction adopts the TIA, says yes. That trumps Tesla's manual.

Cheers, Wayne

 

[brycenesbitt]

Yet the 2020 NEC (625.54), or the 2017 NEC if your jurisdiction adopts the TIA, says yes. That trumps Tesla's manual.
Cheers, Wayne

Tesla's instructions here are specific to the hardwired unit. 625.54 applies to "All single-phase receptacles".
Is there anything that would require the GFCI breaker for the hardwired EVSE?