Car charger circuit 3 wire or 4 ?

hillbilly1

Senior Member
Location
Atlanta,Ga
Occupation
Field coordinator/ technical support
The car charger itself is straight 208-240. The older Eaton charge controllers only used the neutral for the contactor. Like dryers, they didn’t know wether it would be used on 208 or 240, and at the time, they (Eaton) didn’t make a 208-240 coil. With Tesla, I think the owner orders the charge controller with the plug that matches the existing. I don’t think they allow adapters.
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
Not knowing which Elec car a customer is getting, should we run 3 or 4 wires? They want 60 amp capacity. Thank you.
An EVSE is 240V only, so if it is hardwired, 2+1 will do. Some plug in EVSEs use a NEMA 14 plug, in which case you need a neutral for the NEMA 14 receptacle. But I believe that at 60A it will be hard wired.

Cheers, Wayne
 

hillbilly1

Senior Member
Location
Atlanta,Ga
Occupation
Field coordinator/ technical support
An EVSE is 240V only, so if it is hardwired, 2+1 will do. Some plug in EVSEs use a NEMA 14 plug, in which case you need a neutral for the NEMA 14 receptacle. But I believe that at 60A it will be hard wired.

Cheers, Wayne
Unless it is an early Eaton, but yes, the vehicle itself is 208-240 only.
 

WA_Sparky

Electrical Engineer
Location
Vancouver, WA, Clark
Occupation
Electrical Engineer
Just ran into this a month or so back. You only need to run 208-240/2 40A, 2wire+gnd. All cars will take 40A/2 but some cars can utilize more amperage draw, therefore I've been putting in 60A/2 to accommodate for all car types.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
If a 4-wire plug is supplied, a 4-wire receptacle required, right?

If a 4-wire receptacle is installed, doesn't a neutral have to be run and connected?
 

suemarkp

Senior Member
Location
Kent, WA
Occupation
Engineer
You don't know what the future holds. Could be Tesla today, Ford tomorrow. Run a neutral. Some EVSE won't need it, and really I don't know why they need them. But many EVSEs use a 14-50 plug so I would allow for one of those to be connected at some point.
 
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