4256A25G02 is the classic legacy Westinghouse part number, and 1C31025G06 is Emerson’s unified official spare part number for this high-performance second-generation MRC main remote control board. This module serves as the core communication master unit for remote I/O racks of Ovation WDPF distributed control systems, fully plug-and-play compatible with all previous MRC series models including 4256A25G01, 4256A25G02/1C31025G04 and 4256A25G02/1C31025G05 without any system configuration adjustments. Upgraded with advanced main control processor, expanded data cache and optimized high-speed bus transmission algorithm, it delivers lower transmission latency and faster redundant channel switching speed to support super-large multi-rack DCS clusters with massive remote I/O nodes. Built with multi-layer high-temperature resistant FR-4 PCB and full electromagnetic shielding structure, it adopts 1000V AC/DC galvanic isolation between field bus terminals and internal logic circuits to resist severe electromagnetic interference from high-voltage equipment, inverters and rotating machinery on heavy industrial sites. Every board passes complete factory qualification tests such as 72-hour high-low temperature cycling aging, full-load long-time communication burn-in and fault simulation, equipped with surge, overvoltage, overcurrent, reverse polarity and short-circuit multi-level hardware protection, as well as LED diagnostic lights for real-time status and fault indication to simplify on-site maintenance and reduce unplanned production shutdown loss.