The National Electrical Manufacturers Association (NEMA) has assigned designations to the various configurations. The purpose of so many different types is to prevent the wrong combinations of electrical systems from being plugged together, thereby avoiding potentially dangerous conditions. If you have a NEMA code number for a device, use this table to help determine the device ratings.

  NEMA     X     5     -     15     P  

     
    X
     
      X is the position occupied by L for locking devices. If no letter us present, the device is non-locking, straight blade.
     
    5
     

      5 indicates the voltage*
      • 2 indicates 115 VAC, ungrounded for Class II connections
      • 5 indicates 125 VAC, grounded for Class I connections
      • 6 indicates 250 VAC, grounded for Class I connections
      • 7 indicates 277 VAC, grounded for Class I connections
      • 8 indicates 480 VAC, grounded for Class I connections
      • 9 indicates 600 VAC, grounded for Class I connections
      • 14 indicates 125/250 VAC, single phase, four wire, three pole
      • 15 indicates 250 VAC, three phase, four wire, three pole
      • 16 indicates 480 VAC, three phase, four wire, three pole
      • 17 indicates 600 VAC, three phase, four wire, three pole
      • 18 indicates 120/208 VAC, ungrounded, three phase, four wire, four pole
      • 20 indicates 347/600 VAC, ungrounded, three phase, four wire, four pole
      • 21 indicates 120/208 VAC, three phase, five wire, four pole
      • 22 indicates 277/480 VAC, three phase, five wire, four pole
      • 23 indicates 347/600 VAC, three phase, five wire, four pole
      15  

      15 indicates the current rating and standard values are:
      • 15 amps
      • 20 amps
      • 30 amps
      • 50 amps
      • 60 amps
     
    P
     

      P Indicates plug or receptacle
      • P: is plug
      • R: is receptacle

    *excludes for Class II connections


  • 2-POLE 2-WIRE

  • 2-POLE 3-WIRE

  • 3-POLE 3-WIRE

  • 3-POLE 4-WIRE

  • 4-POLE 4-WIRE

  • 4-POLE 5-WIRE