FANUC A02B-0303-C205 I/O Interface Module

The A02B-0303-C205 is a compact I/O module designed for use with FANUC Series 0i, 16i, 18i, 21i, and 30i CNC controllers. It functions as a remote I/O unit on the FANUC I/O Link (high-speed serial bus). The module typically provides 16 digital inputs (24 VDC) and 16 digital outputs (transistor, 0.5A) plus 2 analog inputs (0-10V) and 2 analog outputs (0-10V). It is widely used to connect machine tool peripherals such as coolant valves, tool changers, limit switches, and spindle sensors.

Technical Specifications

• Digital Inputs: 16 points, 24 VDC (sink/source), optocoupler isolated

• Digital Outputs: 16 points, NPN transistor, 24 VDC, 0.5 A per point

• Analog Inputs: 2 channels, 0–10 VDC, 12-bit resolution

• Analog Outputs: 2 channels, 0–10 VDC, 12-bit resolution

• Communication: FANUC I/O Link (2 Mbps, dedicated protocol)

• Power Supply: 24 VDC (from I/O Link cable or external)

Physical and Environmental

Dimensions: 110 mm × 78 mm × 45 mm (L × W × H). Weight: 0.25 kg. Mounting: DIN rail or screw holes. Protection class: IP20. Operating temperature: 0 to 55°C; storage: -20 to 70°C; humidity: 30–95% non-condensing. Vibration: 0.5G at 10–55 Hz. The module has a front-facing LED array for each I/O point and a green power/status LED.

Compatibility and Configuration

This module is compatible with all FANUC CNC that support I/O Link (standard on most 0i and 16i/18i systems). Configuration is performed via CNC PMC (Programmable Machine Controller) ladder software: assign I/O addresses in the PMC configuration table. The module automatically receives its node ID from the CNC during power-up. Up to 16 modules can be daisy-chained on a single I/O Link.

Applications

Typical uses include machining centers (for tool magazine sensing), lathes (for turret position feedback), and robotic cells. The analog inputs can read pressure sensors or analog potentiometers, while analog outputs drive spindles or hydraulic valves. The A02B-0303-C205 is a drop-in replacement for older A02B-0300 series modules with same form factor.

Reliability

MTBF is calculated at 250,000 hours (ground benign). The module includes a watchdog timer that resets outputs if I/O Link communication fails. An internal isolation barrier withstands 1.5 kV between field and logic. The board is conformal coated for protection against coolant mist.