Signal : F0.4
Symbol : SPL
Description : Feed hold signal
Detail : CNC will inform the PLC that feed hold is given by user.

The F0.4 (SPL) flag is typically activated when the operator presses the feed hold button on the CNC panel to temporarily stop the machine’s motion. In response, the PLC would typically:

• Pause or hold the feed motion of the machine.
• Stop all movements related to the current machining operation (e.g., cutting, positioning).
• Allow the operator to inspect or adjust the machine settings.
• Provide the option to resume the feed or perform further actions when the operator deactivates the feed hold.

When encountering the SP9019 SSPA:19 Excess Offset Current U error message indicating that there is an abnormality in a spindle amplifier component and that the initial value for the U phase current detection circuit is abnormal, it suggests an issue with the spindle amplifier’s ability to detect and manage current properly. Here’s how to address this issue:

Steps to Troubleshoot and Resolve the Issue

1. Power Cycle the Machine: Turn off the CNC machine completely, wait for a few minutes, and then turn it back on. This can sometimes reset temporary errors.
2. Check Connections: Inspect all electrical connections related to the spindle amplifier, especially those connected to the U phase. Ensure that all connectors are secure, clean, and free from corrosion.
3. Examine the Spindle Amplifier: Check the spindle amplifier for any visible signs of damage, such as burnt components or physical wear. If the amplifier is damaged, it may need to be replaced.
4. Measure Phase Currents: Use a multimeter to measure the actual current flowing through the U phase and compare it to the expected values. An abnormal reading could indicate a fault in the amplifier or motor.
5. Verify Settings and Parameters: Ensure that the machine’s parameters related to the spindle and current detection circuits are set correctly. Incorrect settings could lead to abnormal readings.
6. Inspect the Motor: Check the spindle motor for any issues, such as short circuits or open windings. An abnormal motor condition can affect current detection.
7. Replace the Spindle Amplifier: If all other checks are inconclusive and the error persists, replacing the spindle amplifier may be necessary to restore normal operation.
8. Consult Technical Documentation or Support: Refer to the Fanuc technical manuals for specific diagnostic procedures related to the SP9019 error, or contact Fanuc support for further assistance.

Abnormality in spindle amplifier ID data is detected. Replace the Spindle Amplifier.

Steps to Troubleshoot and Confirm the Cause

1. Reboot the CNC: Power down the CNC completely, wait a few minutes, and power it back up. Sometimes, temporary system glitches cause ID reading errors that a restart can clear.
2. Inspect and Secure Connections: The communication between the CNC controller and the spindle amplifier relies on stable connections. Check all cables and connections related to the spindle amplifier to ensure they are properly seated and free of dust or corrosion.
3. Verify Power Supply and Environmental Conditions: Ensure the spindle amplifier is receiving a stable power supply and that the CNC’s environment is free from excess dust, heat, or humidity, which could interfere with normal operations.
4. Check for Software or Parameter Errors: In rare cases, ID data errors could be related to software or parameter issues within the controller. Ensure your machine’s software is up to date and that all parameters related to the spindle amplifier are correct.
5. Replace the Spindle Amplifier: If all connections are secure and the issue persists, the spindle amplifier may have an internal fault, such as damaged circuitry or memory, which necessitates replacement to restore function.
6. Consult Fanuc or CNC Technician: If you’re uncertain about the error or if replacing the amplifier is challenging, consult with Fanuc technical support or a certified CNC technician.

Based on the information provided, here are descriptions for each step and related question concerning the Fanuc SP9015 SPINDLE SWITCHING FAULT:

1. Check and correct the ladder sequence.

   This step involves examining the CNC machine’s ladder logic to ensure that the sequence of operations is correctly programmed. An incorrect ladder sequence may lead to improper spindle switching and trigger the SP9015 fault.

2. Replace the switching MC.

   The switching magnetic contactor (MC) may be faulty if it fails to engage or disengage properly. Replacing a defective MC can resolve issues where the mechanical switching is not occurring as expected, leading to the SP9015 fault.

3. The switch sequence in spindle switch/output switch operation is abnormal.

   An abnormal switch sequence during spindle or output switch operations indicates a potential issue in the control logic or hardware. Verifying and correcting this sequence is crucial to ensure proper machine operation and avoid the SP9015 fault.

4. The switching MC contact status check signal and command do not match.

   If the status check signal of the switching MC does not align with the command being given, it suggests a discrepancy that can cause the machine to detect an error. This mismatch needs to be resolved to clear the SP9015 fault.

Each of these descriptions and questions addresses specific troubleshooting actions or considerations for resolving the SP9015 fault in Fanuc CNC systems.