UL 698A UL Standard for Safety Industrial Control Panels Relating to Hazardous (Classified) Locations

Title
UL Standard for Safety Industrial Control Panels Relating to Hazardous (Classified) Locations Underwriters Laboratories Inc.
Scope:
             These requirements cover industrial control panels intended for general industrial use and installation in unclassified locations with intrinsically safe circuit extensions into Class I, Class II, and Class III, Division 1 hazardous (classified) locations in accordance with the National Electrical Code, NFPA 70.
             The industrial control panels covered by these requirements are not intended for metal working machine tools, plastic injection molding, power press controls, flame safety supervision of combustible fuel type equipment, or elevator controls.
             These requirements do not cover electrostatic devices, circuits or systems, gas or vapor analysis equipment or other equipment having a process line brought into an enclosure.
             The industrial control panels covered by these requirements are assemblies consisting of components such as motor controllers, overload relays, fused disconnect switches, and/or circuit breakers and related control devices such as push button stations, selector switches, pilot lights, timers, switches, control relays and the like with associated wiring terminals. In all cases, the enclosure is provided as part of the assembly.
These requirements cover equipment for use under the following atmospheric conditions:
  • a) An ambient temperature not exceeding 40C (104F);
  • b) An oxygen concentration not greater than 21 percent by volume; and
  • c) A nominal barometric pressure of one atmosphere.