What is the official UL definition of a panel?
UL considers an industrial control panel an assembly incorporating two or more pieces of industrial control equipment or related control circuit devices, provided with interconnecting wiring and terminals for connections in the field. To allow the installer to properly install the panel in accordance to the national electrical code and other codes, electrical ratings and instructions are to be clearly explained on the panel. Installation can be completed in two ways: in an enclosure as “enclosed type” equipment, or arranged onto a mounting panel as “open type” equipment. For open type equipment, the assembly is installed in an enclosure or at the installation site.
