UL 508C

Standard for Power Conversion Equipment

1.1 These requirements cover open or enclosed equipment that supplies power to control a motor or motors operating at a frequency or voltage different than that of the input supply. These requirements also cover power-supply modules, input/output modules, Silicon Controlled Rectifier (SCR) or Transistor output modules, dynamic braking units, and input/output accessory kits for use with power conversion equipment.

1.2 This equipment is for use in ordinary locations in accordance with Articles 430 and 440 of the National Electrical Code, NFPA 70.

1.3 These requirements cover devices rated 1500 volts or less.

1.4 Equipment intended for use in hazardous locations as defined by the National Electrical Code, NFPA 70, shall be evaluated to the Standard for Explosion-Proof and Dust-Ignition-Proof Electrical Equipment for Use in Hazardous (Classified) Locations, UL 1203.


  • Edition Number: 4
  • Edition Date: 05/16/2016
  • Price Code: B
  • Type: ulstd
  • ANSI Approved: 05/16/2016
  • DOD Approved: