What charger(s) do I want/need for 2023 MY or M3?

[mknmike]

@stripes I'd read on a DIY forum about a guy in Canada installing a Grizl-e. It was my understanding that they are a little cheaper than the Tesla as you mention. If I would like the option of being able to park the tesla in/near the garage or in the driveway, it might be nice to have two chargers for flexibility in life. At that point, it's actually 2x the difference I'm looking at. So $100 or $200 turns into $200 or $400. While I'd like flexibility, I don't see any sense in pissing away money if the Grizl-e is just as functional as the Tesla charger. Plus maybe being cheaper I'll feel more comfortable painting it to match my house if it's an eyesore.

I'll see if I can post pictures from my phone to help explain why I would want chargers in both locations.

On the mobile charger, it sounds like if I just get a table for it to sit on and wrap it in plastic, I can leave it outside as long as I'm sure the cords are not leading water to the unit, but back to the ground without hitting the unit.

 

[Supcom]

@stripes I'd read on a DIY forum about a guy in Canada installing a Grizl-e. It was my understanding that they are a little cheaper than the Tesla as you mention. If I would like the option of being able to park the tesla in/near the garage or in the driveway, it might be nice to have two chargers for flexibility in life. At that point, it's actually 2x the difference I'm looking at. So $100 or $200 turns into $200 or $400. While I'd like flexibility, I don't see any sense in pissing away money if the Grizl-e is just as functional as the Tesla charger. Plus maybe being cheaper I'll feel more comfortable painting it to match my house if it's an eyesore.

I'll see if I can post pictures from my phone to help explain why I would want chargers in both locations.

On the mobile charger, it sounds like if I just get a table for it to sit on and wrap it in plastic, I can leave it outside as long as I'm sure the cords are not leading water to the unit, but back to the ground without hitting the unit.

You should have an electrician give you a bid to install whatever you are considering. Assuming you plan to wire to 240VAC, 50A, or similar, you need the electrician to tell you if your current service and/or breaker box can handle the current requirements of two, or even one, EV charger.

Many houses electrical service cannot accommodate two additional 50-amp EV services. Tesla Wall Connectors can share power to alleviate this.

 

[mknmike]

I consulted an electrician when running the new underground wires to my detached garage, and decided to install a 100 amp panel in the garage that currently runs everything in there on a single 15 amp breaker. The breaker in the main panel will most likely be an 80 amp breaker in the house to assure the 100 amp panel does not overload the aluminum wire that is downgraded from 100 amps to 90 amps due to the material and length of the run. Basically, for the garage, we are going to be totally fine. Then we got the space in the house to run another dual-breaker outlet. So I’m pretty sure I’m good. I will likely do the same as what I did with the electrician when we removed the service line that was directly above the swimming pool and moved it underground. I ran all the wires and conduit, and the PoCo and Electrican handled the connections. I’m pretty confident I could handle the Wall Charger installation, and we will likely live here forever, eliminating the need for an inspection sticker to be able to sell the house. Still, we will cross that bridge when we get to it regarding whether the Wall charger needs to be inspected in my local (which follows the national code).

 

[mknmike]

The level 1 3-5 mph charge rate just sunk in, and I now understand that at the very least, to buy some REAL time, I’m going to want a setup for 240v. I’ve got a mb old unused wall air conditioner in the dining room next to the driveway where I was anticipating ripping it out and re-doing the stucco and maybe running the needed wires to the outside through the new stucco. However, now I’m wondering if I could put a weather-protected 240v outlet in there that would enable level-2 charging in the driveway until I get a wall charger setup.

Anyway, I think I could maybe get by for a short period with level 1, but understand that I will want more very quickly.

 

[Beans4Me]

With your annual mileage I’d try to get your level 2 charging plan sorted out before you take delivery. I’ve been level 1 for the past few months and it’s doable but inconvenient. Every minute matters so you gotta keep your car plugged in all the time. In order to use the car as we normally would we had to supercharge. Not the end of the world but we had to go out of our way at times to do so. With level 2 it’s not even something that you have to think about.

With regards to power at your home, you really need to perform a load calculation to understand if your service can support two level 2 evse. I’m guessing you don’t have enough and you will need to utilize power sharing. Btw, you can link up to 6 tesla wall connectors to power share.

 

[mknmike]

With your annual mileage I’d try to get your level 2 charging plan sorted out before you take delivery. I’ve been level 1 for the past few months and it’s doable but inconvenient. Every minute matters so you gotta keep your car plugged in all the time. In order to use the car as we normally would we had to supercharge. Not the end of the world but we had to go out of our way at times to do so. With level 2 it’s not even something that you have to think about.

With regards to power at your home, you really need to perform a load calculation to understand if your service can support two level 2 evse. I’m guessing you don’t have enough and you will need to utilize power sharing. Btw, you can link up to 6 tesla wall connectors to power share.

We will only have one EV for several years into the future, at least until we pay off the first one anyway.

 

[mknmike]

Wow. I went nuts on another DIY forum inspecting my options, and finally got some 1” conduit through the wall next to my circuit breaker box. I don’t know whether I’m going to end up with a temporary or permanent setup. I know there are benefits of the permanent wall charger like easier code-installation with no need for a GFCI breaker, as it gets hard-wired, but I’m pretty sure we are also going to want to have the ability to charge when boondocking like at my in-law’s vacation house. So the mobile charger really is a “must-purchase”. I could really keep costs down with an illegal setup and no GFCI and a plug. I could also keep all of this dry outside too, but none of that would make it legal.

So it seems like we will really want both chargers.

I may investigate whether some non-Tesla brand wall chargers could possibly make more sense. Too bad there’s really no way to legally use level-2 mobile charging without a GFCI breaker.

 

[Beans4Me]

Ya your best bet is to get something permanent for the home and a mobile unit to keep in your car (if you feel the need for mobile charging). I'd avoid using a mobile as your primary and plugging/unplugging as that could lead to premature failure of your receptacle, especially if you buy a cheap big box receptacle.

 

[mknmike]

Ya your best bet is to get something permanent for the home and a mobile unit to keep in your car (if you feel the need for mobile charging). I'd avoid using a mobile as your primary and plugging/unplugging as that could lead to premature failure of your receptacle, especially if you buy a cheap big box receptacle.

I’m thinking more along the lines of leaving the mobile charger plugged in at home, and packing it when going on a trip. That could be the temporary solution until I decide to replace the outlet with a wall-mounted charger.

 

[RayK]

I’m thinking more along the lines of leaving the mobile charger plugged in at home, and packing it when going on a trip. That could be the temporary solution until I decide to replace the outlet with a wall-mounted charger.

I don't think it has been addressed so far in this thread, but if you are contemplating getting a current model Standard Range or RWD 3 or Y, know that the maximum charging current those cars can take is 32A. You can certainly plan on installing a 60A circuit for a Wall Connector and have it provide 48A to change a car, but unless you get an AWD or Performance, the car is limited to 32A. The Mobile Connector is also limited to supplying 32A max., given it's plugged into a 50A circuit/outlet.

Edit: NVM, I said this back on Oct. 6th. Brain fart... that's my excuse...

 

[mknmike]

I don't think it has been addressed so far in this thread, but if you are contemplating getting a current model Standard Range or RWD 3 or Y, know that the maximum charging current those cars can take is 32A. You can certainly plan on installing a 60A circuit for a Wall Connector and have it provide 48A to change a car, but unless you get an AWD or Performance, the car is limited to 32A. The Mobile Connector is also limited to supplying 32A max., given it's plugged into a 50A circuit/outlet.

Edit: NVM, I said this back on Oct. 6th. Brain fart... that's my excuse...

Thanks for bringing that to my attention. Does this mean that a standard range M3 and MY is also incapable of supercharging?

LFP battery issue?

I was assuming a huge benefit of a wall charger is getting that 48 amp charge rate on a 60 amp circuit.

 

[RayK]

No, all Teslas can Supercharge. It's only a question of Level 2 (240VAC) charging where the 32A limit kicks in for SR/RWD models. There's charging modules in the car that convert AC voltage to the DC voltage of the battery. Two modules of 16A each are in the SR/RWD cars. The AWD/Performance models have 3 modules for a total of 48A. No difference between the LFP and NMC batteries; it's just the number of modules Tesla deemed to be needed for each model. Lower cost car = lower charging rate.

edit: Note that this is true for current RWD models. My own 2018 RWD is capable of 48A charging, although I've only ever connected to 24A L2 service before (had free ChargePoint charging at work).

edit: Consult Tesla Model 3 Specification Table for specs: AC charging (per hour).

 

[mknmike]

No, all Teslas can Supercharge. It's only a question of Level 2 (240VAC) charging where the 32A limit kicks in for SR/RWD models. There's charging modules in the car that convert AC voltage to the DC voltage of the battery. Two modules of 16A each are in the SR/RWD cars. The AWD/Performance models have 3 modules for a total of 48A. No difference between the LFP and NMC batteries; it's just the number of modules Tesla deemed to be needed for each model. Lower cost car = lower charging rate.

edit: Note that this is true for current RWD models. My own 2018 RWD is capable of 48A charging, although I've only ever connected to 24A L2 service before (had free ChargePoint charging at work).

edit: Consult Tesla Model 3 Specification Table for specs.

Ok. So this certainly changes my plan to install a 60 amp breaker on 100 amp AL wire to a 60 amp service disconnect to be able to install a short length of copper wire. I sure am glad this was brought to my (poor) attention. Sorry I didn’t catch it earlier, but very very glad I caught it now. Thank you!

Ok. So these chargers need a 25% increase in the amps using some weird 25% rule. 48 amp charger needs 60 amp breaker and wire. 60. That’s 12 more than 48. That’s 25% of 48. So 25% of 32 is 8. So a 40 amp breaker with 40 amp wire is really all I need. Right?

And if I want to say F the wall charger bc my car can’t really use it, I can just find a 40 amp GFCI breaker. And then have a permanent setup and leave my mobile charger in a protected box and call it done. If I want it to be permanently setup and not have to unplug it, I buy a second mobile charger to keep in the car. Right?

Am I catching on?

 

[RayK]

It's generally called the "80% rule" when talking about the continuous amount of current that is provided to EV chargers. So, 80% of 60A is 48A, 80% of 30A is 24A and so on.

Yes, as far as the second mobile connector is concerned. If you don't see yourself buying another EV (Tesla) in the next few years that can take more than 32A of charging current, then a "permanently" installed mobile connector in your garage and a second (spare) one kept in your car for traveling / emergencies should work. My own mobile connector lives in my car but I've never used it outside of my house in the 5+ years I've had my car. I choose not to have home charging at the moment since there's a nearby CHAdeMO station which is cheaper than my home electrical service. If I really had to, I'd install the Wall Connector that's still in its original box on the wall of my garage, right behind the electrical panel, with a transfer switch to a 14-50 outlet (for emergency use by my mobile connector) and call it a day.

Your car can use a Wall Connector but not up to its maximum capability (if you are intended to get an RWD or SR). Note that the Wall Connector can be configured to use a number of different breakers; from a minimum of 15A to a maximum of 60A (Gen 3 specs). Also, the Wall Connector is rated to be mounted outdoors (I'd still put in under some sort of cover/hood), while the Mobile Connector is not (at least as a permanent installation).

 

[mknmike]

I just now see that the different plugs can charge at different rates, but the 32 amp options require 50 amp breakers. Why? I have no idea. That’s not 80%. So I don’t get it, but I can buy a 50 amp breaker instead of the 60 amp I’d initially planned on buying, or the 40 amp spare I have. No big whoop. I just need to know what to buy and where to put it.

I’m probably going to remove the inoperable wall air conditioner and repurpose it’s metal box as a pass through into our dry dining room with no water sources. Therefore I should not need a GFCI breaker for it. That will provide us an option for the fastest home charging we can do, and at an economical price until we decide several things:

- With Tesla backup camera and reverse tire tracks, will my wife become more comfortable backing out of our narrow driveway that has a concrete wall on one side and a stucco house on the other, and an ~8-foot-wide driveway gate?

- Will I get the garage cleaned out enough to be able to park the Tesla inside the detached garage?

This has all been such a learning experience that I do wonder if I should have just hired someone to tell me what to do and pay them for it. Now I know though.

 

[RayK]

32A charging current requires a minimum of a 40A breaker. Because there are no NEMA outlet designs rated for 40A, one can use a 50A design (e.g., a NEMA 14-50) along with a 40A breaker (as long as you use the correct gauge wire AND label the outlet as having a 40A breaker). I believe this is the only exception to the rule of "outlet must match breaker".

As to the GFCI breaker, I believe national code is such that if the outlet is in the garage (or otherwise possibly wet/damp environment), a GFCI is required. A Wall Connector, being hard-wired to the breaker and not going through an outlet, does NOT need a GFCI. At least that's what I gather (I'm not a licensed electrician; consult your own for guidance).

As to backing out using the camera(s), practice makes perfect.

 

[Beans4Me]

The requirement for gfci on 240v receptacles came with the 2020 NEC code revision. It looks like DE adopted 2020 in sept 2021 so you’re required to use a gfci.

My wife can’t backup and will never learn so I went through the added expense of installing it for her pulling forward into the garage.

 

[mknmike]

The requirement for gfci on 240v receptacles came with the 2020 NEC code revision. It looks like DE adopted 2020 in sept 2021 so you’re required to use a gfci.

My wife can’t backup and will never learn so I went through the added expense of installing it for her pulling forward into the garage.

It seems to me that the code requirement is for GFCI for anywhere that is near a wet location, which is basically every stove in a kitchen or every dryer next to a washer, or every dryer in a basement, or every welder plug in a garage, or every EVSE plug outside. For all practical reasons, it seems that is every 240 volt plug. Right?

I created a bit of a controversy on a different forum with electricians by asking if I could install a 14-50 in my dry diningroom and basically run the mobile plug out the window without adding a GFCI breaker. Nobody would condone this, and some said structuring the setup to avoid the code requirements is not legitimate. It seems to me that this could be one of the safest possible setups that will work reliably. My understanding is that there should never be two GFCI protections on the same circuit and that the Tesla mobile charger has some type of GFCI protection built in. The test load from the EVSE can sometimes trip a GFCI breaker (from what I’ve read).


So I’m looking at either installing a 14-50 inside and creating a door designed to allow the cord to safely exit the building (via the wall air conditioner hole that I’ve been planning to close up) or just use my existing 30 amp dryer plug. I know unplugging and re-plugging the dryer plug will probably destroy the receptacle in short order though.

Knowing that the M3 RWD only charges at a max level 2 rate if 32 amps makes the immediate benefit of a wall charger pretty limited for me at this point. Maybe when I clear out the garage I will install one there.

 

[flixden]

It seems to me that the code requirement is for GFCI for anywhere that is near a wet location, which is basically every stove in a kitchen or every dryer next to a washer, or every dryer in a basement, or every welder plug in a garage, or every EVSE plug outside. For all practical reasons, it seems that is every 240 volt plug. Right?

I created a bit of a controversy on a different forum with electricians by asking if I could install a 14-50 in my dry diningroom and basically run the mobile plug out the window without adding a GFCI breaker. Nobody would condone this, and some said structuring the setup to avoid the code requirements is not legitimate. It seems to me that this could be one of the safest possible setups that will work reliably. My understanding is that there should never be two GFCI protections on the same circuit and that the Tesla mobile charger has some type of GFCI protection built in. The test load from the EVSE can sometimes trip a GFCI breaker (from what I’ve read).


So I’m looking at either installing a 14-50 inside and creating a door designed to allow the cord to safely exit the building (via the wall air conditioner hole that I’ve been planning to close up) or just use my existing 30 amp dryer plug. I know unplugging and re-plugging the dryer plug will probably destroy the receptacle in short order though.

Knowing that the M3 RWD only charges at a max level 2 rate if 32 amps makes the immediate benefit of a wall charger pretty limited for me at this point. Maybe when I clear out the garage I will install one there.

You can always install the wall charger at a later time. The GFCI question is always controversial, it seems, in the forums.
Not sure the door solution is practical in the long run.

 

[fholbert]

I'm sure this has been covered somewhere, but my belief is that I should not need a Tesla charger at all bc I should be able to charge these cars while on the road at a non-tesla charge point. Right? So I'm assuming that when I purchase, I don't need to buy the Tesla mobile or wall connector.

Option 1 - Charge at home while you sleep at a lower rate.

Option 2 - Sit in your car while charging and pay a higher cost for the electricity required.