| 1. | Identification by hour numbers of the phase conductors of 3 - phase electric systems 三相电力系统各相导线的钟点序数识别标志 |
| 2. | Phase conductor not connected to the centre contact of the edison - type screwed lamp holder 相导线并非接驳至螺丝头灯座的中间触点。 |
| 3. | Connecting point for earthing and short circuiting devices ; shell fixing point for phase conductors 接地的接点和短路设备.相导线用外壳的固定接点 |
| 4. | Connecting point for earthing and short - circuiting devices ; bracket fixing point for phase conductors 接地的接点和短路设备.相导线的托架固定接点钢索管 |
| 5. | System category a - - this category comprises those systems in which any phase conductor that comes in contact with earth or an earth conductor , is disconnected from the system with in i min A类系统一一该类系统任何一相导体与地或接地导体接触时,能在lmin内与系统分离; |
| 6. | Ground fault protection this function trips ( opens ) a circuit breaker or sounds an alarm in the event that there is an electrical fault between one or more of the phase conductors and ground ( earth ) 接地故障保护当一个或多个相导线与地之间出现电气故障时,接地故障保护通过跳脱断路器或报警来示警。 |
| 7. | However it is difficult to suspend the multi - phase conductors , furthermore the pole structure is complex , and the cost of transmission lines is high and the types of fault for multi - phase transmission increase rapidly 由于6相及以上多相输电的导线悬挂困难,杆塔结构复杂,故障种类繁多,线路造价上升等缺点,多相输电的推广应用受到了限制。 |