If everyone is following the rules, you shouldn't need that. From the outlet, you should be able to assume the wiring behind it. You could have a 15A outlet with 20A wiring, but I wouldn't try to draw 16A from it. While the wiring could take it, the outlet isn't rated for it.
Tesla has a system kind of what you describe. Their charging cord has changeable ends. From the plug installed, they know the voltage and current capability they should expect. They draw 80% of the rated current. While ramping up the current, they watch the voltage. If it drops too much, they back off the current and warn that the wiring has a problem or an extension cord is being used. It then remembers that maximum current for the next time it charges at that location. Mike On January 20, 2016 7:43:06 AM MST, Seth Rothenberg via EV <ev@lists.evdl.org> wrote: >I have been thinking (dangerous I know) >Is there a way for an instrument (live ohmmeter / ammeter) >or an electronic circuit to recognize the gauge (and surmise >the amperage protection likely in place) ? > >eg, measuring ohms from neutral to ground, >(for 120 circuits) or doing a millisecond high-load >test to see voltage drop? > >(I'm not an Electrician or an EE, but I have faith >in their ingenuity :-) > > >Where would i need this? >For example, I got permission to charge from an inside outlet >at a small building under construction. no idea at this time >if it is 20a. (In this case, I could bring my circuit ID tool >and look in the panel but don't need to at level 1 :-) >(I got my EVSE cable yesterday ! :-) > > > >On Wed, Jan 20, 2016 at 3:28 AM, Bill Dube via EV <ev@lists.evdl.org> >wrote: >> Paul, >> >> There are a number of places in your home that are _required_ by the >> national electrical code to have dedicated 20 amp circuits for the >120V >> receptacles. >> There are at a minimum five (5) 20 amp 120V receptacle circuits in a >modern >> house: >> >https://dbs.idaho.gov/programs/electrical/publications/2014_Homeowner_guide_brochure.pdf >> Sometimes, in a low-cost tract house without a garage there are less, >(and >> in older homes there could be fewer) but typically there are quite a >few >> more. The places that you will find additional dedicated 20 amp >receptacles >> for; the microwave, the garbage disposal, occasionally the >dishwasher, etc. >> Often, the savvy custom home builder will call for upgrades on 20 amp >120V >> receptacles for the patio, pool, workshop area, green house, deck, >workout >> area, home entertainment area, basement, etc. >> >> You will notice that the code requires a 20 amp circuit for the >garage, were >> your EV is likely to be parked. >> >> In commercial buildings, typically _all_ of the 120V receptacles are >20 amp. >> >> I used to be an electrician, many years ago. I wired (and rewired) >> _countless_ houses. :-) >> >> Bill D. >> >> >> On 1/19/2016 2:56 PM, dovepa via EV wrote: >>> >>> A 120volt outlet is usually only rated for 15 amps. >>> >>> >>> >> >> _______________________________________________ >> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >> http://lists.evdl.org/listinfo.cgi/ev-evdl.org >> Read EVAngel's EV News at http://evdl.org/evln/ >> Please discuss EV drag racing at NEDRA >(http://groups.yahoo.com/group/NEDRA) >> >_______________________________________________ >UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >http://lists.evdl.org/listinfo.cgi/ev-evdl.org >Read EVAngel's EV News at http://evdl.org/evln/ >Please discuss EV drag racing at NEDRA >(http://groups.yahoo.com/group/NEDRA) _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
