🛠️ Fanuc 414 Servo Alarm – Z-Axis Detect Error Repack 📌 Alarm Description
Alarm Code: 414 (SV0414) Message: SERVO ALARM: Z-AXIS DETECT ERROR Meaning: The CNC controller detects a mismatch between the commanded position and actual position feedback from the Z-axis servo motor encoder or serial pulse coder (usually for 1 revolution or initial feedback check). Typical Cause: Encoder signal loss, cable break, bad connector, or internal motor encoder failure.
🔍 Step 1 – Alarm Confirmation Check the following before repair: | Check | Action | |-------|--------| | Alarm occurs at power-on or during motion? | Power-on → encoder/cable issue. Motion → mechanical binding or servo amp issue. | | Any other alarms? | 410, 411, 415, 416, 420, 421 indicate related servo/encoder issues. | | Does Z-axis move manually? | If no movement + 414 → probable encoder signal loss. |
🧪 Step 2 – Initial Diagnostics (No disassembly yet) fanuc 414 servo alarm z axis detect error repack
Power off machine and control.
Inspect Z-axis motor encoder cable :
Check for cuts, crushing, oil contamination. Verify connectors at motor side and CNC/servo amp side are fully seated. 🛠️ Fanuc 414 Servo Alarm – Z-Axis Detect
Check servo amplifier (if dual-axis amp, test X/Y first to isolate).
Measure feedback voltage (if accessible):
Encoder power supply: 5V DC at motor encoder connector. Signal lines (P, N) should have ~2.5V bias with pulses when rotating manually. | Power-on → encoder/cable issue
Swap test (if possible):
Swap Z-axis motor with another axis (same model) → if alarm moves → motor encoder faulty. Swap servo amp → if alarm stays on Z → cable or motor encoder issue.