Poor machine grounding or routed power cables running too close to feedback lines can corrupt the digital encoder signals. Step-by-Step Diagnostic Protocol
Low Voltage. The drive lacks sufficient incoming DC link voltage. fanuc 414 servo alarm z axis detect error
Take the motor off the Z-axis and try to move the ball screw by hand. If it is hard to move, the issue is mechanical (gib adjustment, ballscrew, or slideways lubrication). Poor machine grounding or routed power cables running
FANUC Troubleshooting Manual – FANUC CNC FAQ - MRO Electric the issue is mechanical (gib adjustment
Lubricate the ball screws and guide rails regularly to reduce friction.
Swap the Z-axis feedback and power cables with the X or Y-axis at the drive module end.