Fanuc Backpanel (4 slots) for 16i/ 18i/ 21i A20B-2003-0240

A20B-2003-0240 is a CNC I/O interface printed circuit board (PCB) used in control systems manufactured by FANUC.

---

📌 Basic Information

• Part Number: A20B-2003-0240

• Type: Printed Circuit Board (PCB)

• Category: I/O Interface Board

• Used In: FANUC CNC controllers (commonly Series 0 / 0-Mate / early 0i systems)

---

⚙️ Main Functions

The A20B-2003-0240 board is designed to handle machine input and output signals between the CNC controller and the machine hardware.

Typical functions include:

• Receiving input signals from sensors and switches

• Sending output signals to relays, solenoids, and actuators

• Supporting PMC (Programmable Machine Control) ladder logic

• Acting as the interface between the CNC controller and machine electrical devices

---

🧩 Installation Location

This PCB is normally installed:

• Inside the CNC control cabinet

• On the I/O rack or control base unit

• Connected to other CNC boards through the FANUC system backplane

---

🔎 Related Boards

The A20B-2003 board family includes similar I/O boards such as:

• A20B-2003-0230

• A20B-2003-0240

Differences usually involve hardware revisions or I/O configuration variations.

---

✅ Simple explanation:
A20B-2003-0240 = FANUC CNC I/O interface PCB used to connect machine sensors, switches, and actuators to the CNC controller. 🔧