For 208-240V EV charger use:
2-nn not useable -- no ground;
5-nn not useable -- 125V only;
7-nn not useable -- 277V;
11-nn not useable -- no ground;
15-nn and 18-nn useable but not commonly found -- three phase.
Use extreme caution when using a three-phase receptacle, type 15 or 18!
Use a voltmeter to verify that the two legs being used are both approximately 120V to ground.
Revised 9/15/03.
| 30 AMP | 2 pole 2 wire | 2 pole 3 wire grounding | 3 pole 3 wire | 3 pole 4 wire grounding | 4 wire | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| 125V | 250V | 125V | 250V | 277V | 125/250V | 250V | 125/250V | 250V | 120/ 208V | |
| Receptacle |  2-30R |
 5-30R |
 6-30R |
 7-30R |
 10-30R |
 11-30R |
 14-30R |
 15-30R |
 18-30R | |
| Plug |  2-30P |
 5-30P |
 6-30P |
 7-30P |
 10-30P |
 11-30P |
 14-30P |
 15-30P |
 18-30P | |
| 50 AMP | 2 pole 3 wire grounding | 3 pole 3 wire | 3 pole 4 wire grounding | 4 wire | ||||
|---|---|---|---|---|---|---|---|---|
| 125V | 250V | 277V | 125/250V | 250V | 125/250V | 250V | 120/ 208V | |
| Receptacle |  5-50R |
 6-50R |
 7-50R |
 10-50R |
 11-50R |
 14-50R |
 15-50R |
 18-50R |
| Plug |  5-50P |
 6-50P |
 7-50P |
 10-50P |
 11-50P |
 14-50P |
 15-50P |
 18-50P |
| 60AMP | 3 pole 4 wire grounding | 4 wire | |
|---|---|---|---|
| 125/250V | 250V | 120/ 208V | |
| Receptacle |  14-60R |
 15-60R |
 18-60R |
| Plug |  14-60P |
 15-60P |
 18-60P |