Fanuc 7115 — Alarm

: Loose connections or damaged cables between the Spindle Amplifier and the gear switching contactors. Spindle Amplifier Fault

When alarm 7115 appears, follow this structured approach to identify and resolve the issue. The process assumes you have access to the machine’s alarm history and PMC diagnostic screens.

The contactors responsible for switching the winding configuration are worn, dirty, or damaged.

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Have someone operate the machine while listening for the "click" of the contactors. fanuc 7115 alarm

If the alarm occurs immediately upon a spindle command, use a megohmmeter to check the motor windings for shorts to ground or between phases.

Use the CNC diagnostic screen to check the status of switching signals (like MC1, MC2). If a signal is missing, trace it back to the I/O board or the spindle amplifier.

: He checked the physical magnetic contactors responsible for switching the motor windings. A welded or sticky contactor is often the physical culprit behind a 7115 error.

If the robot physically crashed into a hard stop or tripped a limit switch, you must manually jog it backward. Turn on the Teach Pendant. : Loose connections or damaged cables between the

A physical collision can shift components, mechanically jamming the axis and confusing the position feedback loop. Step-by-Step Diagnostic and Resolution Guide

| Bit | Function | Effect on 7115 | | :--- | :--- | :--- | | | Reference point return direction | If set opposite to actual dog approach direction → 7115 alarm |

The FANUC 7115 alarm is a specific warning code that appears on CNC machines utilizing FANUC controls equipped with the conversational programming interface . When this alarm triggers, it halts conversational programming operations and demands immediate troubleshooting.

Ensure all motor leads and feedback cables are securely connected. Users often find issues in the 2-conductor shielded link cables or motor run capacitors. Use the CNC diagnostic screen to check the

The magnetic contactors responsible for switching the spindle windings may be stuck or failing to engage.

The physical overtravel switch or its cable is damaged, sending a false "limit tripped" signal to the controller.

: If power and wiring are confirmed good, the issue may lie within the Spindle Control Board Spindle Amplifier Recommendation : Start by monitoring the 24VDC power supply