24 December 2010

Mini E drivers charging without an EVSE

Todd and Kari with Mini E #140 just posted a link to a You Tube video with Josh from AC Propulsion.  If you look at 4 minutes and 50 seconds, you can clearly see that AC Propulsion has connected a 30 amp, 120 volt "Travel Trailer" plug directly to the charging cord for the Mini E.  This allows them to charge at 3600 watts at a Recreational Vehicle park in the US.  This is more than twice as fast as the usual 110 volt 12 amp yellow charging EVSE (Electric Vehicle Service Equipment) that Mini supplies in the US.  But I find it a bit odd that they are showing this, because the electrical code requires that drawing current at 100% of a connector capacity (30 amps in this case) should be limited to 3 hours, which is not long enough to fully charge the Mini E.  The code says to limit current to 80% of rated capacity when the load duration exceeds 3 hours.  But then again, AC Propulsion can probably set the current draw to 24 amps in their car, which the rest of us cannot do.  We have to live with 12, 32 and 50 amp settings.  (All of which actually draw slightly less than what the setting shows.)

Then I see that MINI-E Driver Stefan Reitmeier from Germany posted a picture of his car plugged into a wall outlet without an EVSE.  Maybe the regulations are more rational in Germany than in the US?

In any case, AC Propulsion has state of the art safety features built into the charging system in the car.  But only an external EVSE can provide the "dead front" connector to the car.  In other words, the connector face stays unpowered until it is actually engaged in the car receptacle.  So although I admit I have charged without an EVSE myself, we should all avoid it whenever possible and stick to the US rules and Mini guidelines.

It is interesting though.  Someday the US rules may change and charging will be more flexible.


  1. Jim, i just answered your comment at Toms blog, but now i see what you mean. Providing a "dead front" is not implemented at the charging stations. You have to consider this when charging (first plug in the car, then plug in to the charger an activate charging by closing the flap or turning the switch. First turn off charging, then deplug the cable from the charger and then from the car.)
    When you use the wallbox or public station, the connector is mechanically fixed to the charger, so a "hot de-plug" is not possible. At the cars side i think in future there will be a similar device (connector according to IEC 62192-2 Type 2 with mechanical interlock)and it will perhaps be checked by the wallbox via the data link. But this is not implemented in the MINI and its socket.
    But when using a normal wall socket via an adapter, this monitoring is not possible.
    I'm not an electrician, but every extension cord plugged in at a wall socket or high power socket does not have a "dead end". So with a connector design offering safe outdoor handling even at adverse weather conditions this should not be a major problem (in case the car has no problem beeing "hot plugged").

  2. Hi Stefan

    So the charging stations in Germany are not SAE J1772 compliant? Nothing equivalent in the ISO specifications to provide the "dead front"? You must not have as many lawyers as we have.


    Sorry it took so long to moderate your comment. I get a lot of spam from Asia and I have not figured out how to get Blogspot to email me when a comment is awaiting moderation.

    And I finally linked your blog to my list on the right.

  3. Stefan

    OK, I found your comment over on Tom's blog. Now I understand, the European system is not a "dead front" connector but a GFI, so it is dead pretty fast if anything goes wrong.

    I will try to lookup IEC 60309 and IEC 62196-2 Type 2 when I get to work, but I do not have as much access to Euro specs as I do for SAE.