Disconnection Alarm

What does 416 mean?

This alarm indicates a loss of connection or communication failure within the servo system of the Fanuc Series 20 CNC. It specifically suggests that the digital servo amplifier has lost its communication link to the motor encoder or the CNC.

• Loose or disconnected feedback cable between the motor encoder and the servo amplifier.
• Broken or damaged feedback cable.
• Loss of connection in the serial communication link between the servo amplifier and the CNC.
• Faulty motor encoder or servo amplifier communication port.
• Excessive electrical noise causing intermittent communication loss.

Click steps to track your progress.

1. 1

   Inspect all motor feedback cables and serial communication cables between the CNC, servo amplifiers, and motors for loose connectors, physical damage, or breaks.

2. 2

   Verify the continuity of the feedback and communication cables using a multimeter or cable tester.

3. 3

   Check for any strong sources of electromagnetic interference (EMI) near the cable runs that could disrupt digital signals.

4. 4

   Examine diagnostic screens for specific sub-codes related to communication errors or encoder status.

5. 5

   If possible, try swapping the suspected cable, encoder, or servo amplifier with a known good one to pinpoint the faulty component.