The FANUC A20B-3300-0443 is an internal axes control card used in compatible FANUC CNC control units. It supports CNC axis and servo-control processing as part of the control-unit hardware architecture and works with the associated main board, CPU card, servo amplifiers and feedback system.

FANUC hardware documentation lists A20B-3300-0443 among the axes control cards for selected Series 30i, 31i and 32i Model A configurations. Compatibility is configuration-specific, so the complete card number, revision, CNC model, axis arrangement and installed control hardware must be confirmed.

A20B-3300-0443 Product Information

Axis and Servo-Control Function

The A20B-3300-0443 operates inside the CNC control unit and participates in axis-control and servo communication functions. It should not be confused with an external servo amplifier: the card processes control functions, while the amplifier supplies power to the connected servo motor. Final operation also depends on the CPU, software, parameters, amplifiers, FSSB connection and feedback devices.

Compatibility and Card Selection

Compare the complete A20B-3300-0443 marking, PCB revision, connectors, component layout and mounting interface with the original card. Also verify the CNC series, main-board number, CPU card, controlled-axis quantity, HRV configuration and FSSB path. A20B-3300-0440, -0441, -0442, -0444, -0445, -0446, -0447 and -0448 should not be treated as automatic substitutes.

Testing and Installation Notes

REACO CNC checks the model marking, PCB revision, connectors, optical interface, electronic components, alarm status and axis-control operation where suitable test equipment is available. Back up CNC parameters, programs, offsets, PMC data and servo settings before replacement. Installation should be performed by qualified personnel using anti-static protection.

Related resources: FANUC CNC and robot parts and FANUC control board repair services.