Fanuc 7115 Alarm -
The is a Spindle Switching Control Alarm (SPN1 7115). It typically occurs on machines equipped with a spindle switching function—such as those with high/low gear winding—when the system detects an inconsistency or failure during the switching process. Common Causes
The majority of electrical faults are connection issues. Once the machine is safe to work on, visually inspect all the cables associated with the alarming axis. This includes the thick motor power cables, the thinner encoder feedback cables, and any connectors on the amplifier itself. Look for any signs of damage, looseness, or corrosion.
If your machine has a two-speed gearbox, the problem could be mechanical, not electrical. A mechanical obstruction can prevent the gears from meshing, causing the contactor to stall. fanuc 7115 alarm
An IPM is a heavy-duty electronic switch responsible for sending high-voltage power to your CNC motors. When the IPM detects an irregular electrical spike, extreme heat, or a short circuit, it instantly triggers Alarm 7115. This cuts power to the axis to prevent catastrophic hardware melting or fires. Primary Causes of Alarm 7115
If these steps do not resolve the issue, you may need to contact a FANUC repair specialist to test the spindle amplifier or replace the logic board. The is a Spindle Switching Control Alarm (SPN1 7115)
On gearboxes, sensors that detect gear position may be misaligned or broken. Troubleshooting and Solutions: Step-by-Step
: 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. Once the machine is safe to work on,
Set bit 4 (APZ) to 0, then manually jog the machine to its physical home position. Change bit 4 (APZ) back to 1. Cycle the machine power. Preventive Maintenance Tips Schedule Battery Changes
The insulation inside the servo or spindle motor has broken down, creating a direct short-to-ground.
