Reader/Puncher Interface Alarm

What does 87 mean?

This alarm indicates an issue with the communication or interface between the CNC (Fanuc Series 20) and an external reader/puncher device. It prevents proper data input or output operations.

• Incorrect connection or wiring of the reader/puncher interface cable.
• Improper settings of the reader/puncher parameters (e.g., baud rate, data bits, stop bits, parity).
• Malfunction of the external reader/puncher device itself.
• Noise interference affecting serial communication lines.
• Issue with the CNC's interface circuit board.

Click steps to track your progress.

1. 1

   Verify all cable connections between the CNC and the reader/puncher device for proper seating and integrity.

2. 2

   Check the reader/puncher interface parameters in the CNC (e.g., Parameters 10-14 for I/O channel settings) and on the external device, ensuring they match.

3. 3

   Test the reader/puncher device with another known good CNC or test the CNC with a known good external device if possible.

4. 4

   Inspect the communication lines for signs of damage or excessive electrical noise. Ensure proper grounding.

5. 5

   If the issue persists after external checks, consider that the CNC's I/O interface board may be faulty.