Electric Vehicle Charger Installations - Max Current Allowed?

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dave6288

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Portable Electric Vehicle EVSE Chargers are generally plugged into a dedicated 6-20R or 14-50R receptacle.

What is the max current that a EVSE Charger can draw from these dedicated receptacles? What is the code section that covers this?

This would be similar to an 14-50 outlet for an electric range. ie can range pass UL if it draws 50 Amps?
 
dave6288 said:
Portable Electric Vehicle EVSE Chargers are generally plugged into a dedicated 6-20R or 14-50R receptacle.

What is the max current that a EVSE Charger can draw from these dedicated receptacles? What is the code section that covers this?

This would be similar to an 14-50 outlet for an electric range. ie can range pass UL if it draws 50 Amps?
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Ranges have demand factors that reduce rating we are allowed to use. 12 kW would draw 50 amps @ 240 volts, but a 12 kW range would seldom ever draw full 12 kW for very long before an element cycles off for the purpose of maintaining a set point temperature.

Table 220.55 basically allows us to treat a 12 kW range as a 8 kW load. More then one range and the load per appliance allowed is even less.

EV chargers are not covered by that section though. If it comes with a 50 amp cord cap already installed, it probably draws more then 30 amps but less then 51. If it is considered a continuous load it probably draws more then 24 amps but less then 41.
 
EVSE article 625

EVSE article 625

625.44 (B) 2014 NEC is where I'd look, I've installed many EVSE the answer is that the max load any electric vehicle will draw from a receptacle is 40 amps. The Nema 14-50 for a tesla mobile connector for ex, the receptacle wire and breaker or all OCP in the circuit should be rated at 125% of the maximum load. The tesla will draw 40 amps when plugged into a nema 14-50. It will go up to 80 amps when plugged into a tesla wall connector. The cars adjust themselves to the appropriate draw in most cases
 
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