A20B-8200-0663 Fanuc PCB Board A20B82000663 A2OB-82OO-O663

A20B-8200-0663 | FANUC 21i-B Control Main CPU PCB — PMC-SB7 / Without Ethernet / Machining and Turning Centre CNC

Series 21i-B — High-Performance Mid-Range CNC

The FANUC Series 21i-B occupies a strong mid-range position in FANUC's i-series CNC product line — more capable than the 0i-B (economy tier) but more compact in hardware architecture than the full-scale 30i/31i series.

The 21i-B delivers:

• Multi-axis simultaneous control for complex machining and turning
• PMC-SB7 for robust machine sequence control
• Advanced servo and spindle performance for precision machining
• High-speed look-ahead contouring for smooth feedrate control in contoured cutting

The A20B-8200-0663 is the central CPU board for this platform — the master PCB that coordinates all CNC functions.

Key Product Information

W/O Ethernet — The Standard Non-Network Configuration

"W/O Ethernet" indicates this main CPU board configuration does not include the embedded Ethernet interface. This is the standard board variant for Series 21i-B installations that:

• Do not require DNC network connectivity from the CNC control unit
• Operate in environments where programme loading uses other methods (RS-232C, memory card)
• Do not need network-based data collection or monitoring

The "without Ethernet" variant simplifies the hardware — fewer interface circuits on the board, no Ethernet connector, and slightly lower cost than the Ethernet-equipped variant.

Application Scenarios

Series 21i-B CNC main board failure: A machining centre or turning centre with 21i-B control develops CNC system failures. After SRAM backup, the A20B-8200-0663 is replaced. SRAM data is restored and the 21i-B CNC returns to service.

21i-B non-network installation: A Series 21i-B CNC lathe in a standalone machine tool cell without network connectivity uses the A20B-8200-0663 (W/O Ethernet) as its main board.

FAQ

Q1: Can the W/O Ethernet version be upgraded to add Ethernet?

The Ethernet function requires the Ethernet-equipped main board variant — it is not a field-addable option on the W/O Ethernet board (A20B-8200-0663). If Ethernet connectivity is needed, the appropriate main board with Ethernet embedded must be specified when sourcing.

Q2: What is the difference between PMC-SB7 on this board and the PMC-SB2 on older CNC boards?

PMC-SB7 provides significantly more capability than PMC-SB2 — more ladder programme steps (32,000 vs 8,000 in SB2), larger data register count, and faster PMC scan cycle. The SB7's expanded capacity accommodates the more complex machine tool sequences of modern multi-function machining centres and turning centres without programme size restrictions.

Q3: Must SRAM data be backed up before replacing A20B-8200-0663?

Yes. All CNC parameters, PMC ladder programme, part programmes, and tool data must be backed up before replacing the main board. After fitting A20B-8200-0663, all data must be reloaded from backup. The FANUC Series 21i-B Maintenance Manual details the complete backup and restore procedure.

Q4: How does the Series 21i-B differ from the Series 0i-B in terms of capability?

The Series 0i-B (economy platform, A16B-3200-0491 main board described in this series) is optimised for cost-effective standard CNC applications — 2-4 axis lathes and machining centres with standard complexity. The Series 21i-B (this board) provides a higher capability tier — more axes, more advanced servo features, and greater PMC capacity. The two series serve different machine complexity levels and are not hardware-interchangeable.

Q5: What SMD memory modules does A20B-8200-0663 require?

Like other FANUC i-B generation main boards, the A20B-8200-0663 accommodates plug-in FROM (system software), DRAM (working memory), and SRAM (parameter/programme storage) modules. The specific module part numbers required depend on the CNC's software version and installed options.