The A20B-8200-0543 is a FANUC 0i-D MAIN PCB A3, a critical high-performance CNC main CPU board designed for Fanuc Series 0i MD/TD/Mate-MD controllers. It serves as a central control board for managing motion and automation in CNC machines, ensuring fast processing and reliable operation in industrial environments.

• Part Number: A20B-8200-0543 (also fits A20B-8200-0543/02A).
• Compatibility: Designed for Fanuc 0i-D series, often mounted behind LCD panels for CNC machines and lathes.
• Function: Serves as the main control board, managing logic and motion, often holding dedicated processors and RAM/FROM cards.
• Condition: Available from various suppliers, including new, used, and sometimes in-stock for immediate industrial maintenance.
• Notes: Often requires a core exchange, and some units may have specific configurations (e.g., fully populated vs. empty).

This component is commonly used in industrial CNC retrofits and automation repairs, often sourced through industrial suppliers like Fanucworld or on platforms like eBay.