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OpenEVSE 48 Amp and NEMA 14-60R receptacle - NEC Code

NEC 210.19 and 210.20 state that Overcurrent protection devices and conductors need to be sized to 125% of the load when the load is continuous... Or that the load must be 80% of the breaker and conductor rating when continuous, depending on if you like division or multiplication better.

48 is 80% of 60.

60 is 125% of 48.

Any way you slice it, one needs a 60 Amp circuit for a 48 Amp EVSE.


NEC 625.13 I think limits cord and plug installations to 50 Amps circuits. 60 Amp EVSEs need to be hard wired.

Is OpenEVSE offering non NEC compliant hardware or am I reading the code wrong?

You are reading the code right. NEC has added a bunch of new contradictory rules in their latest version.

NEMA 14-60R are technically prohibited by NEC in the US.

Also NEC now requires GFCI on receptacles including NEMA 14-50 which is too sensitive for EVs pulling many thousands of watts at 6ma. The standard for EVs is 20ma.

Additionally, NEC now requires all stations with adjustable current to be hardwired, essentially eliminating just about every plug in station on the market.

The latest NEC is a mess for EV charging, contradicting many established standards by others, including SAE J1772 and UL 2231.

Doesn't NEC require EVSE to be listed?  So, is any of this actually relevant to OpenEVSE since it's not listed? 


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