Reliance 0-57423-E Common Memory Module (57C423) provides 128K bytes of memory for Reliance Electric AutoMax PLC systems, delivering a centralized, battery-backed store for common variables and system data used by the rack. Designed for use with M/N 57C413B and 57C423 processors, it is typically installed in slot 0 of a rack to serve as the bus arbiter and memory backbone for the backplane. To preserve its contents during power loss, the module requires an external battery backup (57C492). The 0-57423-E designation is the cross-reference for the 57C423 Common Memory Module, a configuration commonly listed in Automax literature and reseller catalogs for Reliance Electric systems.
