中文
含义
U1 为反相保护（三相电源机型）。电源相序接反。
常见原因
- 安装时电源相序接反
- 维修后相序恢复错误
- 供电线路改换导致
自助排查
- 使用相序表检测三相相序
- 调整任意两相接线位置
- 联系电工处理
English
Meaning
Reverse phase protection (three-phase models). Power supply phase sequence is reversed.
Common Causes
- Phase sequence reversed during installation
- Phase sequence restored incorrectly after maintenance
- Supply line modification
Self-Check Steps
- Test phase sequence with phase meter
- Swap any two phase wires
- Contact an electrician