bigedgar wrote:Thanks for all the info in this thread, everyone. I've been investigating the same 240v / 16amp Duosida unit that others have. My only issue is around the plug options. At the location where I intend to use this, I have a 240v / 30 amp circuit available (served by two hots, a neutral and a ground). These EVSE units seem to typically come with a 10-30 or 6-20 plug, and I've also been offered a 14-50 plug. But there are issues with all the plug options:
2. 10-30 plug: As far as I understand, most 240v EVSEs have two hots and a ground - no neutral. 10-30 receptacles have two hots and a neutral. So I don't understand how the 10-30 configuration is electrically sound. Does it bank on the neutral in the 10-30 receptacle being bound to the earth-ground back at the panel? If so, that seems a little risky, as my understanding is that the neutral wire is always capable of back-feeding electricity.
4. 14-50 plug: See #1 (can't have a receptacle that doesn't match the amperage of the circuit). I suppose I could order it in this configuration, and then remove the 14-50 plug and just re-wire a 14-30 plug onto it.
While technically obsolete the 10-30 plug is still in millions of houses and you can still buy them. The ground is shared with the neutral but in your case you won't be using the neutral so that wire/pin will just be used for ground. While ground and neutral are generally separate at the outlet and wiring, they both attach to the same point inside your electrical panel, they are bonded together. If your not comfortable with that then just do as wwhitney said and use a 14-50 plug/outlet. Note if using a 14-50 outlet without a neutral you might also run into code issues. The 14-50 is supposed to have a netural and if you don't wire one and then someone down the line plugs in something requiring a neutral.....A better option for EVSE use is the 6-50 which lacks a neutral, unfortunately, very few EVSEs use that more fitting plug as the 14-50 is more likely to be found in peoples homes.
I'm not sure what kind of Leaf you have but if your Leaf is capable of more than 16a(3.6kw charger) I'd really suggest spending a bit more and getting the Zencar adjustable EVSE. They output up to 30a(27.5a in your case) and would make more use of your 30a service. Just get yours configured for a 24a option, you can pick up to 4 output settings. The Zencar is much nicer than the bare bones simple Duosida EVSE and still <$300.