Thanks for your insight. Yes, the breaker will be 20 amps so if anyone tries to do anything other than a single L2 or two L1's they will loose both as the breaker will trip. I do assume that a 20A 2 pole breaker actually will trip based on an overload on either of the two sides independently of what is on the other.
Thanks! Bob On Sun, Feb 17, 2019 at 7:32 PM Jay Summet via EV <email@example.com> wrote: > > > I install two 120v outlets on each post along with a single 240v outlet. > > And then a small note says, "Either one L2 or two L1's but not both". > > Each post has properly rated #10 conductors for the 16 amps on Line1 and > > Line2 and Ground and a #12 for Neutral since the Neutral carries either > > zero or only the 12 amps of a single L1. > > > > > > Is this legal under the NEC? > > It depends entirely upon your breaker size. As long as you don't have a > breaker larger than 20 amps on either phase you should be good to go. > > I'm worried about you sizing the neutral smaller than the hots, as > somebody may see the 10 AWG hot line and put a 30 amp breaker on it, not > realizing the neutral wire still needs to be limited to 20 amps. > > I'm also worried about the ability for somebody to overload one of your > hots by plugging into both the L2 and an L1 at the same time. > > A polite sign isn't the same as an interlock. You must assume some bozo > will plug into the L2 and both L1's at the same time. > > (I assume the two 120v L1 outlets are on opposite phases of a split > phase 240 setup for the 240v outlet.) > > For example, if somebody sets up a space heater that draws 15 amps on > one of the L1 outlets, and then somebody else starts to charge their car > at 16 amps on the 240 outlet, the total number of amps on one of your > hots would be 31 amps, which is more than should be going over a 10 AWG > wire. If you had a 20 amp breaker no problem. If you are using a 30 > amp breaker, no problem for the 240 volt circuit, but somebody could > successfully draw 25 amps over your 10 AWG neutral if they (for example) > had a 30 amp 120v RV circuit going through a 15 amp plug adapter. > > So either the breaker must trip because it's a 20 amp, or all the wires > including the neutral must be sized to accommodate the full possible > load, 10AWG for a 30 amp breaker. > > Jay > > > > _______________________________________________ > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > Please discuss EV drag racing at NEDRA ( > http://groups.yahoo.com/group/NEDRA) > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20190217/6e45c515/attachment.html> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)