代码 421: SERVO ALARM: n AXIS EXCESS ER (D)
问题描述与安全警告
Fanuc 16i/18i/21i CNC 触发了严重的 SERVO ALARM: n AXIS EXCESS ER (D) 警报。需要由合格的操作员或维修技师立即处理，以防止在制造周期中对设备造成二次损坏或导致零件报废。在接触电气控制箱之前，请务必确保遵循标准安全和停机挂牌 (LOTO) 程序。
官方故障排除步骤
The difference between the errors in the semi–closed loop and closed loop has become excessive during dual position feedback. Check the values of the dual position conversion coefficients in parameters No. 2078 and 2079.
Source: Fanuc Series 16i/18i/21i-B Operator's Manual, Appendix G Alarm List (B-63864EN/03)
Last reviewed: 2026-07-01 · Verified against the manufacturer’s official documentation.
关于 Fanuc 16i/18i/21i CNC 警报
由 Fanuc 制造的工业控制器具有广泛的诊断系统，用于保护内部电路和机械连杆。当 16i/18i/21i CNC 出现类似 421 的错误代码时，通常表示指令值与实际传感器反馈之间存在不匹配。
完整报警清单: 360 Fanuc 16i/18i/21i CNC 代码s.
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