hardwire EVSE and secondary L6-20 type receptacle...

[ljwobker]

Trying to figure out the most elegant and future proof way to set this up... I'm an engineer by training but have little practical experience in the world of residential wiring... all the theory makes sense, but I don't know the building codes for anything.

I'll get the upgraded Nissan EVSE, which supports 16A charging and uses an L6-20 plug. I'm likely going to have an AV or Schneider (not sure yet) installed too, but no matter what I want to go ahead and get a 30A/7.2kW capable EVSE day one rather than a 16A.

*Ideally* I think what I'd want to do is run a new 40A rated circuit from the panel, and on the other end I would put both the EVSE itself *and* a junction box with an L6-20 receptacle. The point here is to have the L6-20 available for backup purposes only... one question is whether or not it's legal from a code standpoint to run both the hardwired EVSE and the receptacle onto the same circuit...

In that same line of thinking, I *might* even decide I want to run a 50A circuit at some point... so if I do this, I can run the circuit with 8AWG wire (rated to 50A) then install a two pole 40A breaker in the panel... then wire up the L2 wall-mount EVSE, and also install a couple of junction boxes, one with the L6-20 that I need for the upgraded EVSE, an "empty" junction box to future-proof the install... so if at some point I want to put an L6-30 or even an L6-50 receptacle I can do that... or if I need to take the EVSE down off the wall to upgrade it, I can do that too.

I figure that the incremental cost of doing 8AWG and a couple of "unnecessary" junction boxes the first time around will save me a ton of headache and work down the road... does that logic make sense?

(And rest assured that I'll have a real electrician do the actual wire termination work, but part of the fun for me is making sure I understand how it all works together...)

 

[ElectricVehicle]

Put a NEMA 6-50 connector as the only receptacle on that circuit. The 40A Leviton and the Blink, possibly others will plug into that and it meets code.

For your EVSEUpgrade, make an L6-20 to NEMA 6-50 adapter cable and plug it in to the NEMA 6-50 receptacle until you upgrade to a 32A EVSE.

 

[EVDRIVER]

Put a NEMA 6-50 connector as the only receptacle on that circuit. The 40A Leviton and the Blink, possibly others will plug into that and it meets code.

For your EVSEUpgrade, make an L6-20 to NEMA 6-50 adapter cable and plug it in to the NEMA 6-50 receptacle until you upgrade to a 32A EVSE.

This is the best and easiest solution.

 

[wwhitney]

*Ideally* I think what I'd want to do is run a new 40A rated circuit from the panel, and on the other end I would put both the EVSE itself *and* a junction box with an L6-20 receptacle.

That's not going to fly with the NEC--any 20 amp receptacle needs to protected by a breaker of 20 amps or less. You could put a 50 amp receptacle on the 40A circuit along with the EVSE, that would be an interesting question whether it is OK without an interlock to keep both of them being used at once. I'm a little unclear on that.

so if I do this, I can run the circuit with 8AWG wire (rated to 50A)

The current rating of #8 Cu wire depends on the wiring method, for NM cable (romex), it is only good for 40 amps; other wiring methods can use the 75C rating of 50 amps.

Cheers, Wayne

 

[wwhitney]

Put a NEMA 6-50 connector as the only receptacle on that circuit. The 40A Leviton and the Blink, possibly others will plug into that and it meets code.

As far as I know, if it would be more convenient, you could put two or three NEMA 6-50 receptacles on one 40A or 50A circuit.

Cheers, Wayne

 

[ljwobker]

As far as I know, if it would be more convenient, you could put two or three NEMA 6-50 receptacles on one 40A or 50A circuit.

This is the direction I'm now leaning... a 40A rated circuit, with #8 wire, two 6-50 outlets (one on each side of the garage)

 

[smkettner]

With two outlets I believe you will need a subpanel with the appropriate sized breakers.

If you want future proof run 100 amps (or more if required by Tesla ) to the subpanel and you can swap breakers as needed as you upgrade.

 

[KJD]

How many days does Raleigh get to be over 100 F ?

What are the temps inside your garage on these hot days ?

The higher temps seem to age the LEAF battery faster than it should. Here in SLC we have about 3 months where it gets over 100 F on a regular basis. On these hot days I park my LEAF outside of the garage so that the car can cool down as much as possible at night.

You might want to put one outlet inside the garage and one outlet on the outside of the garage by the driveway. Just make sure you get an outdoor rated box if you decide to go this route.