Fanuc A16B-1200-0220 PC Memory Board
The Fanuc A16B-1200-0220 is a PC memory board used in Fanuc F3 control CNCs (Series 15, 16, 18). It provides non‑volatile SRAM storage for part programs, tool offsets, parameters, and macros. The board is installed in the main CNC rack and communicates with the main CPU via the backplane bus. It is essential for expanding memory capacity beyond the base CPU.
Memory Specifications
Type: 1 MB SRAM (static RAM) organized as 1M x 8 bits.
Battery backup: Lithium battery (BR‑2/3A or CR2032) retains data for 5 years.
Access time: 100 ns.
Data retention during battery change: 1 hour (supercapacitor).
Board Layout
The board measures 150 mm x 100 mm, FR‑4 material, UL 94V‑0. Key components: four 256K x 8 SRAM chips (e.g., Sony CXK581000), a battery holder, a voltage supervisor (MAX691), and an address decoder PAL (16V8). A 3‑position DIP switch configures the memory address range (A0–A19).
Connectors
J1 (96‑pin DIN 41612): Backplane connector for address/data bus.
J2 (2‑pin header): External battery connection (optional).
J3 (4‑pin header): Diagnostic LED and write‑protect jumper.
LED Indicators
LED1 (green): Power OK. LED2 (yellow): Write enabled. LED3 (red): Battery low. A push‑button (SW1) allows manual battery test.
Compatibility
The A16B-1200-0220 is used in Fanuc Series 15‑B, 16‑B, 18‑B, and 21‑B CNC systems. It is also compatible with Fanuc Power Mate i series. It replaces earlier A16B-1200-0221 (same form factor). Not compatible with i‑series (16i) which use different memory boards.
Configuration
The board’s address range is set by DIP switches SW2 (4 bits). The CNC automatically recognizes the memory during power‑up if configured correctly. Write protection can be enabled via jumper JP1 to prevent accidental program modification.
Battery Replacement
Replace the battery every 4–5 years (Fanuc part A02B-0160‑K201 or standard CR2032). Remove power, open the cabinet, locate the battery on the board, and replace within 1 minute. After replacement, verify parameter checksum and reload if necessary.
Environmental
Operating temperature: 0 to 50°C; storage: -20 to 70°C. Humidity: 10% to 90% non-condensing. The board is conformally coated to prevent corrosion.
Typical Applications
Storing large part programs (e.g., 1000+ lines), tool life management data, and macro programs in CNC machining centers, lathes, and grinding machines.
Ordering and Documentation
Fanuc part number: A16B-1200-0220. Manual: Fanuc Series 15/16 Maintenance Manual (B-62545E).
