The FANUC A20B-2101-0355 is an αiSP command board used in compatible FANUC αi Series spindle amplifier systems. It is also commonly described as a spindle control board, spindle amplifier control PCB, or command PCB.

Installed within the spindle amplifier, this board supports control-command processing, spindle operating coordination, internal signal communication, and interaction with the associated power and driver circuitry.

FANUC maintenance documentation lists the A20B-2101-0355 as the printed circuit board used across several αi SP Type B spindle amplifier configurations. Referenced models include αi SP 2.2 through αi SP 55 in applicable configurations, as well as selected high-voltage Type B units. Exact compatibility still depends on the complete amplifier model and hardware configuration.

The board is suitable for replacement when a confirmed PCB fault causes spindle amplifier startup problems, unstable spindle operation, command errors, communication faults, or failure of the amplifier to operate normally.

• Spindle control functions tested before shipment
  
• Stock available for prompt dispatch
  
• Worldwide DHL, UPS, and FedEx shipping

Product Details

• Brand: FANUC
• Part Number: A20B-2101-0355
• Alternative Format: A20B21010355
• Type: αiSP Command Board / Spindle Control PCB
• Product Series: A20B-2101
• Amplifier Family: FANUC αi Series Spindle Amplifier
• Referenced Configuration: αi SP Type B
• Application: FANUC CNC Spindle Drive Systems
• Function: Spindle command processing, control coordination, and internal signal communication
• Category: FANUC Spindle Amplifier PCB / Drive Control Board

Compatibility Note

FANUC documentation associates the A20B-2101-0355 with multiple αi SP Type B amplifier models, but this does not mean it can be installed interchangeably in every αi spindle amplifier.

Before ordering, please verify:

• Complete spindle amplifier model number
• Full PCB part number and revision
• Type A or Type B amplifier configuration
• Input-voltage configuration
• Original wiring board and power PCB numbers
• Connector layout and installed components

For higher-output amplifier units, the A20B-2101-0355 may operate together with a separate driver PCB, so the complete board configuration should be checked before replacement.

Common Use Cases

• FANUC αi spindle amplifier command-board replacement
• Spindle amplifier startup fault diagnosis
• Repair of unstable spindle commands or control signals
• Troubleshooting internal spindle-drive communication faults
• Restoration of compatible αi SP Type B amplifier units
• Preparation of a tested spare PCB for CNC maintenance

Sales & Support

Each A20B-2101-0355 command board is inspected and tested under applicable conditions before delivery.

Worldwide delivery is available through DHL, UPS, FedEx, and other express carriers. REACO CNC provides PCB repair service, warranty coverage, and technical assistance for FANUC spindle amplifier boards and CNC drive components.