IEEE 420-1973 - IEEE Trial Use Guide for Class 1E Control Switchboards for Nuclear Power Generating Stations
Standard Details
This document applies to all Class IE control switchboards (for example, main control room assemblies, auxiliary panels, local panels or racks, etc) as defined in Section 3, regardless of their application or location. It does not apply to the non-Class IE control switchboards, except as they affect the Class IE control switchboards, but recognizes that Class IE control switchboards may be adjacent to, or joined with, other non-Class IE control switchboards. This document includes, but is not necessarily limited to, design, construction, wiring practices, shipping, handling, storage, installation, testing, and quality assurance. General design practices which are not unique to Class IE control switchboards are not addressed in this document. This document applies to piping systems and Class IE equipment only as they may affect the integrity of the Class IE control switchboard.
Superseded by
Board Approval
Working Group Details