Level 2 adapter suggestions?

[timesinks]

I posted this on another thread - might be helpful to some here

I've been trying to read through all of the information on home charging and deciding how to wire for my impending R1T (sOOn). I've developed this table of info but want to make sure it's accurate - so please, those with more knowledge chime in and I will edit to correct inaccuracies:

Type	Charge Amps	Circuit Amps	Plug Type	Miles / Charge Hr
Riv Portable Chrgr			Reg 120v	~3
Riv Portable Chrgr	32A	40A	NEMA 14-50	~15
Plug-in Charger*	40A	50A	NEMA 14-50	??
Riv Wall Charger	48A	60A	Hard Wired	Up to 25

* Non-Rivian plug-in Chargers (JuiceBox, ClipperCreek, etc.)

Assuming this is all correct, and given I don't put a lot of miles on my car any day (max ~50), I'm going to wire my house with a NEMA 14-50 plug and start by using the Rivian Portable Charger - the car will be available to charge 8 hours each night - that should be more than enough for my simple (non-trip needs). I can always juice it up over a couple of nights if I know I'm about to go on a trip.

If I find I want a little more umph, I can later buy a plug-in wall charger from a non-Rivian manufacturer. Also, if my wife gets an EV down the road, then I may choose to get a load-sharing 3rd party plug-in charger.

I do still have one question. Just to maximize my electrician's time (and lower my cost), would I be able to have them install a 60 amp circuit and connect that to the NEMA 14-50 plug? Or is the plug rated for a MAX amperage of 50 amps (as it's naming would suggest). My thinking would be if later I (or a new owner of my home if we sell) wanted to install a hard-wired charger, having the 60 amp circuit in place already would be helpful. But maybe that won't work??

Hope that's helpful to others as well!

One minor difference that can affect project cost... a 50A receptacle for an EVSE needs to be GFCI protected. This is definitely true here in WA with 2020 NEC but also true in many other places on 2017 that have adopted the related interim amendment.

50A GFCI breakers are generally over $100 and have been having supply problems. 2020 NEC also requires hardwire installs to be GFCI protected up to and including 50A circuits.

Going to a 60A breaker for a hardwire 48A unit eliminates this requirement -- and non-GFCI 60A breakers are usually around $15.

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[Joel]

I have a Wallbox unit (available on Amazon) and it works for my Tesla (with the J1772 adapter). I only installed in preparation for my R1S and to get the tax credit for 2021 so it doesn't get use, I only tested. Its rated for outdoor use, so not sure where you plan on installing at work. Its app controllable so you can lock it down if you want and only authorize specific people to use ... never tried that functionality, but see it in the app.


Amazon Link

I also have wallbox. Love it. We had a chargepoint prior it had some issues in the cold. We switched to Wallbox and never looked back. we have 3 at our house and then installed at both my parents houses.

At our house 2 load share and the third is on its own. My son has a M3, I have a Polestar 2, and my wife has a hybrid XC90. They work great.

 

[EarlyAdptr]

One minor difference that can affect project cost... a 50A receptacle for an EVSE needs to be GFCI protected. This is definitely true here in WA with 2020 NEC but also true in many other places on 2017 that have adopted the related interim amendment.

50A GFCI breakers are generally over $100 and have been having supply problems. 2020 NEC also requires hardwire installs to be GFCI protected up to and including 50A circuits.

Going to a 60A breaker for a hardwire 48A unit eliminates this requirement -- and non-GFCI 60A breakers are usually around $15.

Thanks @timesinks ! That may definitely change the thinking

I remember reading somewhere recently that Rivian recommended NOT using a GFIC breaker (maybe it was from you?). But I can’t remember if that was a comment related to their portable charger or the hard-wired charger or both. Any idea?

 

[Rousie13]

I also have wallbox. Love it. We had a chargepoint prior it had some issues in the cold. We switched to Wallbox and never looked back. we have 3 at our house and then installed at both my parents houses.

At our house 2 load share and the third is on its own. My son has a M3, I have a Polestar 2, and my wife has a hybrid XC90. They work great.

Are you load sharing on a 50A or 60A circuit, and do you have the 40A or 48A units? I currently have a pair of the 40A units on a 50A circuit, so they run at 20A each when both are running.

 

[Joel]

Are you load sharing on a 50A or 60A circuit, and do you have the 40A or 48A units? I currently have a pair of the 40A units on a 50A circuit, so they run at 20A each when both are running.

I have the 48a models running on 60amp. They share based on request from the vehicle and tend to adjust.

 

[RivianMN]

I remember reading somewhere recently that Rivian recommended NOT using a GFIC breaker (maybe it was from you?). But I can’t remember if that was a comment related to their portable charger or the hard-wired charger or both. Any idea?

Likely it was related to the hardwired wall charger. Those (usually) have them built in. My inspector said a GFCI breaker was not necessary for hardwired units (as long as it has the GFCI built in).

I just failed my electrical inspection because I didn't have GFCI breakers for the two 14-50 outlets I put in. The 50 amp GFCI breakers are hard to find and when you do, they are usually double the cost what they should be.

 

[Voronbrg]

I just received by wallbox 48amp version. Does anyone know why it comes with a 8awg cord? 8awg is rated for 40amps not the 48 amp as advertised on the unit itself.

 

[timesinks]

I just received by wallbox 48amp version. Does anyone know why it comes with a 8awg cord? 8awg is rated for 40amps not the 48 amp as advertised on the unit itself.

Are you talking about the cord on the vehicle side?

The short answer is the flex cord for connecting to the vehicle has a different ampacity table.

Safe amperage is generally not how much current the copper can handle, but how much heat the insulation can. Different insulations hold up to higher heat.

So your cord might get a little toasty while it's in use, but I would be shocked (pun intended) if they weren't using the correct calculations for sizing that cable.

 

[Voronbrg]

Are you talking about the cord on the vehicle side?

The short answer is the flex cord for connecting to the vehicle has a different ampacity table.

Safe amperage is generally not how much current the copper can handle, but how much heat the insulation can. Different insulations hold up to higher heat.

So your cord might get a little toasty while it's in use, but I would be shocked (pun intended) if they weren't using the correct calculations for sizing that cable.

yes on the vehicle side. is there a chart listed somewhere with this table?

 

[timesinks]

yes on the vehicle side. is there a chart listed somewhere with this table?

Can you identify exactly which cable type they used? There should be identifying markings printed on the cord.

Edit to add:

I suspect you'll see both 6AWG and 8AWG marked on there -- 8AWG for the ground wire makes sense.

 

[Voronbrg]

this is it

 

[timesinks]

That cable is suitable for up to 105C in dry conditions. Most household wiring is 60C-90C.

It may not technically comply with NEC 2020 625.17 (because of the explicit reference to the 60C column), but again, it's a listed appliance -- the listing laboratory has already determined the device is suitable for this purpose. If you're really concerned about it, ask your local electrical inspector. But I would be confident in trusting Wallbox and the listing laboratory to use the appropriately sized wire.

For what it's worth, the 32A portable charger that comes with the R1T has 10AWG wire. Table 400.5(A)(1) would suggest that should max out at 30A. And neither table 1 or 2 specifically mention cable type EVE. I think the answer is probably in the listing standards, but I don't have those readily available.

 

[Voronbrg]

under e2 @60c it shows 55amps for 8awg. So it appears it's fine, since only 2 conductors are being used as load carrying.

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